Grip Asset Reference

Intermediate40-60 minutesWindowsNotepad++Unity Editor

Grip attachments are the recoil-management layer in the Unturned™ attachment ecosystem. Where barrel attachments modify the weapon's audible and visual signature alongside its spread, and sight attachments alter the aiming picture, grip attachments occupy a distinct mechanical role: they tune the weapon's stability profile with more surgical precision than any other attachment type. A vertical foregrip reduces vertical recoil; an angled foregrip biases its effect toward horizontal kick; a bipod transforms the weapon's statistical behavior entirely when the player is prone, applying aggressive recoil and spread reductions that no standing player can access. This asymmetric access model -- stat-changing properties that only activate while prone -- is unique to the Grip slot and forms the core design constraint that every grip modder must understand before authoring a single .dat field.

This article is the 57 Studios™ complete reference for the Unturned™ grip attachment asset type, governed by the ItemGripAsset class. It documents every .dat field available to grip attachments, the inheritance chain from CaliberAsset and ItemAsset, the prone-only Bipod flag mechanic, the caliber compatibility system that gates attachment access by weapon type, the prefab hook placement requirements, and the balance reference tables that the 57 Studios™ cohort has validated across the community. Worked .dat examples for a vertical foregrip, a bipod, an angled foregrip, and a stub foregrip are included in full. A diagnostic table, a comprehensive FAQ section with seven entries, and a complete authoring checklist close the article.

Documentation source: This article integrates information from the official Smartly Dressed Games modding documentation for the ItemGripAsset class, from field evidence in shipped vanilla .dat files, and from the 57 Studios™ community cohort's empirically validated balance values. Where the official documentation is silent on a field's behavior -- such as the prone-activation constraint on the Bipod flag -- this article provides cohort-validated notes derived from in-game testing.

Who this article is for

This article is written for Unturned™ mod authors who have already completed at least one firearm attachment mod of another type -- a barrel attachment or a tactical attachment -- and are familiar with the master bundle pipeline, the Unity prefab workflow, the .dat file format, and the English.dat localization system. If the modder is authoring a gun mod from scratch and needs grip attachments to pair with it, the recommended reading order is Gun Mod Tutorial first, then Attachment Slots: Sight, Grip, Tactical, Barrel for the slot-level overview, then Barrel Asset Reference for the companion barrel attachment type, and finally this article for the grip-specific fields. Modders who are only tuning an existing grip attachment's values (changing Recoil_X or adding the Bipod flag) can skip the gun mod tutorial and begin directly with the field reference table in this article.

What you will learn

• The full class hierarchy from ItemGripAsset through CaliberAsset to ItemAsset and how each parent class contributes fields to the grip attachment.
• Every .dat field available on a grip attachment, including field type, required status, default value, valid range, and gameplay purpose.
• The Bipod flag mechanic -- how stat-changing properties are gated behind the prone condition and what happens when a non-prone player uses a bipod-equipped weapon.
• The caliber compatibility system as it applies to grip attachments, including the universal Caliber 0 convention and custom caliber assignment for exclusive attachments.
• The four stat modifier fields (Recoil_X, Recoil_Y, Spread, Sway) and how each one interacts with the weapon's base recoil and stability values.
• The Hook_Grip prefab placement requirements, including the correct physical position on the weapon model and the forward axis alignment.
• A complete authoring workflow from .dat template to in-game testing, including the pre-bundle checklist.

Background: how ItemGripAsset fits into the asset hierarchy

Every grip attachment in Unturned™ is an instance of the ItemGripAsset class, which inherits from the CaliberAsset class, which in turn inherits from the ItemAsset class. This three-layer inheritance chain means that a grip attachment carries the identity fields from ItemAsset (ID, GUID, Type, Name), the caliber linkage mechanism from CaliberAsset (the Caliber field and its compatibility logic), and the grip-specific fields that ItemGripAsset adds on top (Recoil_X, Recoil_Y, Spread, Sway, and the Bipod flag). A modder who understands the inheritance hierarchy can predict which fields will appear on a grip attachment without memorizing them individually: any field that exists on the ItemAsset or CaliberAsset class is available on every grip attachment by inheritance, and the grip-specific fields are additive.

As shown in the inheritance hierarchy above, the grip asset sits at the third level of the item asset chain, accumulating fields from every parent class on the way. The CaliberAsset class is the same parent that governs barrel attachments and certain other caliber-aware item types, which is why grip attachments carry a Caliber field even though they are not ammunition carriers -- the caliber system gates which weapons can accept which attachments, not just which magazines seat in which guns.

Grip slot within the four-slot attachment system

Unturned™'s attachment system divides weapon modifications into four mutually exclusive slot types: Sight, Grip, Tactical, and Barrel. Each slot type occupies a physically distinct hook GameObject on the weapon prefab and a distinct Type enum value in the attachment's .dat file. The grip slot is the only slot whose statistical effects can be gated behind a player posture condition (the Bipod flag). No other attachment type has this asymmetric activation model -- a barrel suppressor reduces recoil whether the player is standing, crouching, or prone. Understanding this distinction is fundamental to designing a balanced grip attachment set: the grip slot is where the modder applies the most aggressive recoil and spread modifiers, but only when the player is willing to accept the movement penalty of going prone.

The diagram above illustrates four common grip attachment archetypes and their representative stat modifier values, all attaching to the same Hook_Grip position on the weapon prefab. The bipod stands apart because its aggressive modifier values (0.60 and below in most categories) are only applied when the player is in the prone posture, making it the only grip that carries a gameplay condition on its activation.

Grip attachment interaction with weapon fire modes

The grip attachment's stat modifiers interact with the weapon's fire mode in a way that is important for balance tuning across different weapon classes. A weapon in full-automatic fire mode experiences the recoil and spread modifiers on every shot in the burst, meaning the compounded effect of a grip is most visible on automatic weapons where the player can observe the reduced muzzle climb over a sustained firing sequence. A weapon in semi-automatic fire mode experiences the grip's modifiers on each individual shot, but because the player has time between shots to re-acquire the sight picture, the grip's Sway modifier often has more perceived impact on semi-automatic weapons than the Recoil_Y modifier does -- the player feels the steady hold between shots more than the reduced climb per shot. A burst-fire weapon (three-round burst or five-round burst) falls between these two extremes: the grip reduces the recoil over the burst sequence, but the burst is short enough that the compounded reduction is less visible than on a full-automatic weapon.

The 57 Studios™ cohort has validated that a grip with Recoil_Y 0.80 reduces the total vertical displacement of a 30-round full-automatic spray by approximately 20 percent compared to the unmodified weapon. The same grip on a semi-automatic rifle firing at the player's maximum click rate reduces the perceived vertical drift by approximately 10 to 15 percent because the recoil reset between shots partially masks the effect. When authoring a grip for a specific weapon class, the modder should test the grip on the weapon's primary fire mode to confirm that the recoil reduction feels appropriate in the context of that weapon's intended engagement range and fire rate.

File structure for a grip asset

A grip attachment mod follows the same folder layout as any other item mod. Each grip attachment occupies its own subfolder under Bundles/Items/ with exactly three files:

MyVerticalGrip/
├── Asset.dat           ← grip asset definition (fields documented in this article)
├── English.dat         ← display name and description
└── MyVerticalGrip.unity3d   ← master bundle (grip prefab, materials, textures)

The folder name, the .dat filename stem, and the internal Name field should all match. This convention is not enforced at runtime but prevents diagnostic confusion when multiple attachments are being authored simultaneously. The grip prefab in the master bundle is the 3D model that appears on the weapon's Hook_Grip position when the grip is equipped. If the prefab is missing or incorrectly named, the grip will equip statistically (recoil and spread modifiers apply) but will have no visible representation on the weapon.

Complete field reference table

The following table documents every field that a grip attachment's Asset.dat can carry, organized by functional category. Fields inherited from ItemAsset and CaliberAsset are marked with their parent class in the Notes column.

Identity fields

Field	Type	Required	Default	Purpose
ID	uint16	Yes	--	Unique numeric item ID. Must not conflict with any other loaded item. The 57 Studios™ cohort recommends IDs in the 50000+ range.
GUID	uint128 hex	Yes	--	128-bit globally unique identifier. Generate a fresh GUID for every grip attachment using any standard UUID v4 generator; remove hyphens. Never reuse a GUID from another item.
Type	enum	Yes	--	Must be Grip. The engine reads this field to assign the attachment to the Grip slot. Any other value (including Grip misspelled) causes the attachment to be rejected by the slot system.
Name	string	Yes	--	Internal name used for console commands and cross-references. Must not contain spaces. The Name field also serves as the default lookup key for the prefab in the master bundle.
Rarity	enum	No	Common	Determines the inventory highlight color and affects loot table weight interpretation. Valid values: Common, Uncommon, Rare, Epic, Legendary, Mythical.
Slot	enum	Yes	--	Must be None. Grip attachments occupy the weapon's Grip slot, not a player equipment slot. Setting this to Primary or Secondary causes the attachment to consume a hand slot, which is not the intended behavior.

Inventory fields

Field	Type	Required	Default	Purpose
Size_X	uint8	Yes	--	The grip's width in inventory grid cells. Typical values: vertical foregrip uses 1, bipod uses 2 for the folded bipod model.
Size_Y	uint8	Yes	--	The grip's height in inventory grid cells. Typical values: most grips use 2 (vertical grip) or 3 (bipod extended).

Caliber compatibility field

Field	Type	Required	Default	Purpose
Caliber	uint16	Yes	0	The caliber compatibility filter. When set to 0, the grip is universal and equips on any weapon that supports the Grip slot. When set to a non-zero value, the grip only equips if the weapon's Caliber field matches exactly.

Stat modifier fields

Field	Type	Required	Default	Purpose
Recoil_X	float	No	1.0	Multiplier on the weapon's horizontal recoil. Values below 1.0 reduce horizontal kick. Values above 1.0 increase it. At 0.0, horizontal recoil is eliminated entirely. The impact of this field is gated by player posture when the Bipod flag is present: the modifier only applies while the player is prone; standing and crouching players receive no recoil reduction from the grip.
Recoil_Y	float	No	1.0	Multiplier on the weapon's vertical recoil (muzzle rise). Values below 1.0 reduce muzzle climb per shot. This is the most commonly tuned grip field because vertical recoil is the most visible component of weapon stability to the player. The same prone-gating behavior applies when Bipod is present.
Spread	float	No	1.0	Multiplier on the weapon's hip-fire spread (Spread_Hip). Values below 1.0 tighten the cone of fire. This field does not affect Spread_Aim (aim-down-sights spread) directly; aim spread is modified by sight attachments through the Spread_Multiplier_ADS field on the Sight slot. The same prone-gating behavior applies when Bipod is present.
Sway	float	No	1.0	Multiplier on the weapon's idle sway while held and while aiming down sights. Values below 1.0 steady the weapon, making the sight picture more stable and reducing the natural breathing motion. Higher values increase sway, which is rarely used on grips but is available as a design tool for negative-stat grips or cursed attachments. The same prone-gating behavior applies when Bipod is present.
Aiming_Movement_Speed_Multiplier	float	No	1.0	Multiplier on the player's movement speed while aiming down sights. Values below 1.0 slow the player's ADS movement, modeling the weight of the grip attachment. A heavy bipod or weighted handguard might use 0.90 or 0.85 to impose a movement speed penalty that offsets the recoil benefit.

Pro field

Field	Type	Required	Default	Purpose
Pro	flag	No	absent	When present as a bare field (no value), the grip is included in the Pro variant drop pool. Pro variants are cosmetic-enhanced versions of standard items that appear in a dedicated drop tier. Absent the Pro flag, the grip appears only in normal loot tables.

Bipod flag

Field	Type	Required	Default	Purpose
Bipod	flag	No	absent	When present as a bare field (no value), all stat-changing properties on this grip attachment -- Recoil_X, Recoil_Y, Spread, Sway, and Aiming_Movement_Speed_Multiplier -- are only applied while the player is in the prone posture. While standing, crouching, or in any other non-prone state, these fields have no effect on the weapon's behavior. The Bipod flag is the defining mechanic of the bipod subtype and is unique to grip attachments in the four-slot system.

The Bipod flag: prone-only activation explained

The Bipod flag is the most mechanically distinctive feature of the ItemGripAsset class. When a grip attachment carries the Bipod flag in its .dat file, the engine performs a runtime posture check on every frame where recoil, spread, or sway is calculated. If the player's current posture is prone (the player model is lying flat on the ground), the grip's stat modifiers are applied to the weapon's calculated output. If the player is standing, crouching, swimming, climbing, or in any other non-prone posture, the grip's stat modifiers are ignored and the weapon behaves as if no grip were equipped in the Grip slot -- except that the attachment still occupies the slot and still has its visual model seated on the weapon.

The state diagram above shows the posture-driven activation cycle for a bipod-equipped weapon. The critical design implication is that a bipod-equipped weapon is strictly weaker than a standard vertical foregrip for any combat situation where the player is not prone. This makes the bipod a niche attachment that rewards positioning and map knowledge -- the player must identify a firing position where they can go prone, deploy the bipod, and engage targets from that static location. The modder should design bipod stat values to be sufficiently attractive (typically 30 to 50 percent stronger than a standard vertical foregrip) to offset the mobility penalty of going prone.

Bipod does not disable the grip's visual model

When a bipod-equipped player is standing or crouching, the grip's visual model remains visible on the weapon. There is no visual difference between the active and inactive state from the player's perspective or from an observer's perspective. The only indication that the bipod is active is the weapon's statistical behavior. This can be confusing for players who expect a visual deploy animation. The 57 Studios™ cohort recommendation is to document the prone-only activation behavior clearly in the mod's Steam Workshop description and, if possible, to model the bipod in a folded/partially deployed pose for the standing state and an extended/deployed pose for the prone state (achieved through a separate animation state or mesh variant).

Why prone-only activation exists

The prone-only activation constraint exists for gameplay balance reasons, not for technical limitations. In the vanilla Unturned™ weapon set, the bipod is the single most powerful recoil-reduction attachment available: the vanilla bipod applies Recoil_X 0.60, Recoil_Y 0.55, Spread 0.70, and Sway 0.50. If these values were applied while standing, a bipod-equipped assault rifle would have less recoil than a pistol, fundamentally breaking the weapon class balance. By gating these aggressive modifiers behind the prone condition, Smartly Dressed Games ensures that the bipod remains a situational advantage rather than a universal upgrade. The 57 Studios™ cohort has validated that this design constraint is essential for maintaining weapon class identity in modded content: a grip attachment with below-0.70 modifiers should always carry the Bipod flag.

Caliber compatibility system for grip attachments

Grip attachments participate in the same caliber compatibility system that governs barrel attachments, tactical attachments, and sight attachments. The system is a simple integer match between two values: the Caliber field on the attachment's .dat file and the Caliber field on the gun's .dat file. If the values match, the attachment can be equipped. If they differ, the attachment is rejected by the slot system with no visible error message to the player.

As the flowchart above demonstrates, the caliber compatibility check for grip attachments follows the same three-path logic as every other attachment type. A Caliber value of 0 on either side acts as a wildcard, making the attachment universal. This is the standard configuration for most grip attachments: a vertical foregrip should be usable on any weapon that supports the Grip slot, regardless of the weapon's caliber. Custom calibers (values in the 50000+ range) are used when the mod design calls for a grip attachment that is exclusive to a specific weapon family.

Caliber assignment strategy for grips

Grip design intent	Recommended Caliber value	Rationale
Universal grip for any weapon	0	The grip equips on any gun with a Grip slot.
Grip for a specific custom weapon family	Custom value (e.g., 50001)	The grip only equips on guns with the matching custom caliber.
Grip for all vanilla weapons of a given class	Vanilla caliber ID (e.g., 2 for 5.56mm class)	The grip equips on all guns with that vanilla caliber.
Grip exclusive to a single specific gun	Highly specific custom value	The grip equips only on the gun with that exact caliber value, which restricts no other attachments share that caliber value.

Caliber-restricted grip families

The 57 Studios™ cohort recommends reserving caliber-restricted grips for weapon families where the grip geometry is physically incompatible with other weapon types -- for example, a bullpup-pattern foregrip that mounts on the handguard of a specific custom rifle and would not fit on a standard M4-pattern handguard. For most grip attachments, Caliber 0 (universal) is the correct setting because grip attachment geometry is broadly standardized across weapon types in the game's visual design language.

The four stat modifier fields: detailed behavior

Recoil_X (horizontal recoil multiplier)

Recoil_X controls the horizontal component of the weapon's recoil pattern -- the left-right kick that the player experiences with each shot. In the Unturned™ recoil model, horizontal recoil is typically asymmetric: the weapon kicks to the right with each shot (right-hand bias in the animation rig), and the cumulative horizontal displacement creates the spray pattern that the player must compensate for. A grip with Recoil_X 0.85 reduces this horizontal kick by 15 percent, meaning the spray pattern is narrower and more predictable. Values below 0.70 produce a spray pattern so tight that the weapon feels nearly stationary horizontally, which is typically reserved for bipod-configured grips.

Recoil_Y (vertical recoil multiplier)

Recoil_Y controls the vertical component of the weapon's recoil pattern -- the muzzle rise that the player must counteract by pulling down on the mouse. Vertical recoil is the dominant component of the recoil experience for most players because it is the most visible: the muzzle climbs upward with each shot, and the player's sight picture drifts away from the point of aim. A grip with Recoil_Y 0.80 reduces this muzzle rise by 20 percent, which represents a noticeable improvement in controllability. The vertical recoil field is the most commonly tuned grip parameter because it has the most direct impact on the player's perception of weapon stability.

Spread (hip-fire spread multiplier)

Spread controls the cone of fire for hip-fire shooting (firing without aiming down sights). In the Unturned™ weapon model, hip-fire spread is governed by the Spread_Hip field on the gun asset. The grip's Spread value acts as a multiplier on this base value: a grip with Spread 0.90 tightens the hip-fire cone by 10 percent. This is a meaningful improvement for close-quarters engagements where the player fires from the hip rather than aiming down sights. The Spread field does not affect Spread_Aim (the aim-down-sights spread); that value is modified by sight attachments through the Spread_Multiplier_ADS field.

Sway (weapon sway multiplier)

Sway controls the idle weapon sway -- the natural drifting motion of the weapon while the player is holding it, both at rest and while aiming down sights. Sway is the breathing-and-fatigue simulation that makes the weapon feel alive in the player's hands. A grip with Sway 0.80 steadies the weapon by 20 percent, reducing the amplitude of the sway motion. This is particularly valuable for precision shooting at medium to long ranges, where sway can cause the sight picture to drift off target between breaths. The Sway modifier applies to both hip-hold sway and ADS sway.

Combined effect on weapon stability

As shown in the flowchart above, the grip's stat modifiers only enter the calculation chain after passing through the activation check. For grips without the Bipod flag, the activation check always passes and the modifiers are always applied. For bipod grips, the activation check depends on the player's current posture, creating the asymmetric behavior that defines the bipod gameplay trade-off.

Bipod versus standard grip: activation comparison

The following table directly compares the activation behavior of a standard grip (no Bipod flag) and a bipod-equipped grip:

Player posture	Standard grip behavior	Bipod-equipped grip behavior
Standing	All stat modifiers active	No stat modifiers active
Crouching	All stat modifiers active	No stat modifiers active
Prone	All stat modifiers active	All stat modifiers active
Swimming	All stat modifiers active	No stat modifiers active
Climbing / Ladder	All stat modifiers active	No stat modifiers active
Vehicle passenger	All stat modifiers active	No stat modifiers active

Worked .dat examples

Example 1: vertical foregrip (standard)

A universal vertical foregrip with moderate recoil and spread reduction, no caliber restriction, no Bipod flag. This is the most common grip configuration in both vanilla and community content.

ID 50010
GUID a1b2c3d4e5f6a7b8c9d0e1f2a3b4c5d
Type Grip
Name VerticalForegrip_Standard
Rarity Common
Slot None
Size_X 1
Size_Y 2

Caliber 0
Recoil_X 0.85
Recoil_Y 0.80
Spread 0.90
Sway 0.80

Companion English.dat:

Name Vertical Foregrip
Description A standard vertical foregrip that reduces vertical and horizontal recoil. Fits any weapon with an underside rail.

Example 2: bipod (heavy deployment)

A bipod with aggressive stat modifiers gated behind the Bipod flag. The Recoil_X and Recoil_Y values are significantly lower than the vertical foregrip, but they only activate while prone.

ID 50011
GUID b2c3d4e5f6a7b8c9d0e1f2a3b4c5d6e
Type Grip
Name HeavyBipod
Rarity Rare
Slot None
Size_X 2
Size_Y 3

Caliber 0
Recoil_X 0.60
Recoil_Y 0.55
Spread 0.70
Sway 0.50
Aiming_Movement_Speed_Multiplier 0.90
Bipod

Companion English.dat:

Name Heavy Bipod
Description A heavy bipod that dramatically reduces recoil and spread while prone. No effect when standing or crouching. The weight of the bipod slightly reduces ADS movement speed.

Example 3: angled foregrip

An angled foregrip with a bias toward horizontal recoil reduction. Angled foregrips in the 57 Studios™ balance model prioritize Recoil_X reduction over Recoil_Y reduction, creating a distinct handling feel compared to the vertical foregrip.

ID 50012
GUID c3d4e5f6a7b8c9d0e1f2a3b4c5d6e7f
Type Grip
Name AngledForegrip
Rarity Uncommon
Slot None
Size_X 1
Size_Y 2

Caliber 0
Recoil_X 0.80
Recoil_Y 0.88
Spread 0.95
Sway 0.85

Companion English.dat:

Name Angled Foregrip
Description An angled foregrip optimized for horizontal recoil control. Superior lateral stability with a small trade-off in vertical recoil reduction compared to a standard vertical foregrip.

Example 4: stub foregrip (compact)

A minimal-footprint stub foregrip with modest stat reductions across all four categories. The stub foregrip occupies less inventory space (typically Size_X 1, Size_Y 1) but provides weaker modifiers than a full-size vertical foregrip.

ID 50013
GUID d4e5f6a7b8c9d0e1f2a3b4c5d6e7f8a
Type Grip
Name StubForegrip
Rarity Common
Slot None
Size_X 1
Size_Y 1

Caliber 0
Recoil_X 0.95
Recoil_Y 0.95
Spread 0.95
Sway 0.95

Companion English.dat:

Name Stub Foregrip
Description A compact stub foregrip with minimal weight and moderate recoil reduction. Its small size makes it easy to carry as a backup attachment.

Grip balance reference table

The following table provides the cohort-validated balance reference values for the five standard grip archetypes in the 57 Studios™ grip taxonomy. These values are starting points; the modder should tune each field based on the weapon class the grip is intended for and the target server's balance philosophy.

Grip class	Recoil_X	Recoil_Y	Spread	Sway	Bipod flag	Typical rarity
Stub foregrip (minimal)	0.95	0.95	0.95	0.95	absent	Common
Vertical foregrip (standard)	0.85	0.80	0.90	0.80	absent	Common
Angled foregrip	0.80	0.88	0.95	0.85	absent	Uncommon
Weighted handguard	0.88	0.88	0.88	0.88	absent	Common
Bipod (deployed, prone only)	0.60	0.55	0.70	0.50	present	Rare

Balance compounding across multiple attachments

A grip with Recoil_Y 0.55 combined with a barrel attachment carrying Recoil_Y 0.85 produces a combined 0.55 x 0.85 = 0.4675 multiplier on the weapon's vertical recoil. This compounded reduction can produce a weapon that has less than half the recoil of its unmodified version. The 57 Studios™ cohort recommendation is to design grip values so that the fully modified weapon (grip plus barrel plus sight) outperforms the unmodified version by 10 to 25 percent, not by 40 to 50 percent. A weapon that becomes trivial to control removes the skill-based recoil compensation that is a core component of Unturned™'s firearm gameplay.

Hook_Grip placement in the weapon prefab

The Hook_Grip GameObject is the attachment point on the weapon prefab where the grip attachment's 3D model is instantiated at runtime. The hook must be positioned on the underside of the weapon's fore-end or handguard rail at the physical location where a vertical foregrip would attach in real-world firearm design. The local Y axis of the Hook_Grip GameObject should point downward, away from the bore line, so that the grip attachment model extends vertically below the weapon rather than intersecting with the weapon body.

Position reference

The 57 Studios™ cohort has validated the following position guidelines for Hook_Grip based on measurements from vanilla weapon prefabs and community-standard weapon models:

Weapon type	Hook_Grip position	Forward axis alignment
Standard assault rifle	15 to 20 cm behind the muzzle along the bore axis, 3 to 4 cm below the bore centerline	Aligned with bore direction
Carbine / short rifle	12 to 18 cm behind the muzzle, 3 to 4 cm below bore centerline	Aligned with bore direction
Battle rifle / DMR	18 to 25 cm behind the muzzle, 4 to 5 cm below bore centerline	Aligned with bore direction
Light machine gun	20 to 30 cm behind the muzzle, 4 to 6 cm below bore centerline	Aligned with bore direction
Bullpup rifle	8 to 12 cm behind the muzzle (compressed fore-end), 3 to 4 cm below bore centerline	Aligned with bore direction

Reference the vanilla AK or M4 prefab

The fastest way to confirm correct Hook_Grip positioning for a new weapon prefab is to open a vanilla weapon prefab in Unity (the AK or the M4 from the curated bundles) and inspect Hook_Grip's local position. The vanilla positioning is the cohort-validated reference baseline. Measure the offset from the root of the weapon prefab and apply the same offset to the custom weapon.

Case sensitivity warning

The hook name is case-sensitive. Hook_Grip with a capital H, underscore, capital G is the only valid spelling that the runtime recognizes. hook_Grip, Hook_grip, hook_grip, HookGrip (no underscore), and any other casing variant will fail to resolve at runtime, producing an invisible attachment that applies its statistical effects but has no visual model on the weapon.

The positional diagram above shows the approximate location of Hook_Grip relative to the weapon's major sections. The hook should be on the underside of the handguard, not on the receiver and not at the muzzle. The distance from the muzzle is less important than the Y-axis orientation: the grip must extend downward, not sideways or forward.

Glossary

Term	Definition
ADS	Aim Down Sights -- the player posture where the weapon is raised to the eye and the sight picture is visible through the weapon's optic or iron sights.
Bipod	A grip attachment type with the Bipod flag set, causing all stat modifier fields to only apply while the player is in the prone posture.
Caliber	An integer identifier used by the attachment slot system to gate which attachments can be equipped on which weapons based on a simple equality check.
Cohort	The 57 Studios™ internal community of modders whose empirically validated practices form the basis of the balance recommendations in this article.
Foregrip	A grip attachment mounted on the underside of the weapon's fore-end or handguard, typically gripped by the player's support hand.
Grip slot	The attachment slot type assigned to foregrips, bipods, and vertical grips, governed by the Type Grip field in the attachment's .dat file.
Hook_Grip	The Unity GameObject in the weapon prefab that defines the position and orientation where the grip attachment's 3D model is instantiated at runtime.
ItemGripAsset	The C# asset class that governs grip attachment behavior, inheriting from CaliberAsset which inherits from ItemAsset.
Prone	The player posture where the character is lying flat on the ground surface, which is the only posture where bipod-equipped grip stat modifiers activate.
Pro variant	A cosmetic-enhanced version of a standard item that appears in a dedicated high-tier drop pool, enabled by the presence of the Pro flag in the .dat file.
Recoil_X	The horizontal recoil multiplier field on grip attachments, controlling the left-right kick amplitude experienced with each shot fired.
Recoil_Y	The vertical recoil multiplier field on grip attachments, controlling the upward muzzle rise experienced with each shot fired.
Spread	The hip-fire cone multiplier field on grip attachments, controlling the average angular dispersion of fired projectiles when firing from the hip.
Sway	The weapon idle sway multiplier field on grip attachments, controlling the natural drift motion of the held weapon while standing or aiming.

Diagnostic table

Symptom	Most likely cause	Resolution
Grip equips but is invisible on the weapon	Hook_Grip GameObject missing from weapon prefab, or hook name case mismatch	Add Hook_Grip to prefab; confirm exact casing; rebuild bundle
Grip equips at the wrong position on the weapon	Hook_Grip local position is incorrect in the prefab	Reposition the hook in Unity to the underside of the handguard; rebuild bundle
Grip refuses to equip at all	Caliber mismatch between grip and weapon	Set grip Caliber 0 (universal) or match the weapon's Caliber field
Grip equips but has no statistical effect on recoil	Recoil_X or Recoil_Y both set to 1.0 (no reduction)	Set values below 1.0 to produce a meaningful modifier; confirm field names are correct
Grip has no effect while prone (bipod grip)	Bipod flag not set on the grip .dat	Add the Bipod flag to the grip's .dat file
Grip has effect while standing (should be bipod-only)	Bipod flag absent from .dat when it should be present	Add the Bipod flag so modifiers are gated behind prone check
Bipod grip modifiers incorrectly apply while standing	Bipod flag present but engine version handles it differently	Verify against current SDG docs; test on a dedicated server
Grip model clips through the weapon body	Hook_Grip positioned too close to the weapon mesh, or grip prefab pivot is incorrect	Reposition hook or adjust grip prefab pivot in Unity
Grip appears sideways or at wrong angle	Hook_Grip forward axis not aligned with bore direction	Rotate hook so its Z axis aligns with the weapon bore
Grip has no Aiming_Movement_Speed_Multiplier effect	Field name misspelled or omitted	Add the field with the exact casing Aiming_Movement_Speed_Multiplier
Grip consumes player hand slot instead of attaching to weapon	Slot field not set to None	Set Slot None in the .dat file
Pink material on grip model	Material not assigned or shader not found in Unity build	Reassign material and shader in Unity; rebuild bundle
Grip opens in inventory but causes no recoil change	Recoil_X/Recoil_Y/Spread/Sway all set to 1.0 (no-op values)	Reduce at least one stat value below 1.0 to produce a visible effect

Best practices

• Generate a fresh GUID for every grip attachment. Never reuse a GUID from another item, even within the same mod project, because the engine treats GUID collisions as a load-order conflict that silences one of the two items.
• Set Slot None on every grip attachment. The Grip slot is assigned by the weapon, not by the player's equipment slots. Setting Slot to Primary or Secondary causes the attachment to consume a hand slot, which is a bug that prevents the player from equipping both a gun and a melee weapon simultaneously.
• Start with the vertical foregrip values (Recoil_X 0.85, Recoil_Y 0.80, Spread 0.90, Sway 0.80) as the baseline for any standard grip attachment. Tune from this baseline rather than from the grip's extreme values, because the cohort has validated this baseline against the vanilla weapon balance curve.
• Reserve the Bipod flag for grips with at least one stat modifier below 0.70. A bipod with modifiers all above 0.80 is not meaningfully differentiated from a standard grip and creates a gameplay experience where the prone-mobility penalty outweighs the recoil benefit.
• Use Aiming_Movement_Speed_Multiplier as a balancing lever for high-performance grips. A vertical foregrip with Recoil_Y 0.75 (aggressive reduction) should carry a movement speed penalty of approximately 0.95 to create a meaningful trade-off between recoil control and mobility.
• Author the English.dat description to clearly state the grip's activation condition. For a bipod grip, include the phrase "recoil reduction only applies while prone" so that players who inspect the item in the inventory understand the behavior before equipping it.
• Position Hook_Grip first in the weapon prefab before authoring any grip attachment for that weapon. The hook position is the single point of failure for visual correctness, and moving it after attachment assets are authored requires rebuilding all grip prefabs to match the new position.

Advanced considerations

Grip-slot attachment stacking

Unturned™'s attachment system does not support multiple grip attachments on a single weapon simultaneously. Each weapon has exactly one Grip slot, and equipping a new grip replaces the currently equipped one. The dropped grip appears in the player's inventory as a separate item. There is no field or flag that enables dual-grip or multi-grip configurations. Modders who want a weapon to support multiple grip attachments must either combine the functionality into a single grip attachment (a combined vertical and angled foregrip with intermediate stat values) or design the weapon to use a different slot for the second grip (e.g., the Tactical slot, though this visually positions the grip incorrectly).

Grip and barrel attachment interaction

The grip and barrel attachment slots are the two primary stat-modifying slots in the attachment system. When both a grip and a barrel attachment are equipped on the same weapon, their stat modifiers compound multiplicatively rather than additively. A grip with Recoil_Y 0.80 paired with a barrel attachment with Recoil_Y 0.90 produces a combined effective Recoil_Y of 0.80 x 0.90 = 0.72, meaning the weapon experiences 28 percent less vertical recoil than its unmodified state. This compounding effect is the reason why a fully modified weapon (grip, barrel, and sight) can feel dramatically different from the same weapon with no attachments.

The cohort recommendation for mod authors is to design grip and barrel values such that the combined effect of equipping both does not exceed 35 percent total recoil reduction for a standard-quality weapon. A weapon with 35 percent or greater recoil reduction begins to feel trivial to control, reducing the skill-based recoil compensation that is a core element of Unturned™'s firearm gameplay loop. For rare and epic-tier attachment combinations on a battle rifle, where higher-end attachments are intended to provide a meaningful advantage, a combined reduction of up to 45 percent may be appropriate, but this should be validated against the target server's balance expectations before publication.

Grip interaction with weapon spread recovery

The grip's Spread modifier interacts with the weapon's spread recovery rate -- the speed at which the hip-fire cone tightens after firing. In the Unturned™ spread model, each shot increases the current spread value up to a maximum cap defined by the gun's Spread_Hip field. When the player stops firing, the spread value decays back to its minimum over time. The grip's Spread multiplier scales the maximum spread value, not the recovery rate. A grip with Spread 0.90 reduces the maximum spread cap by 10 percent, meaning the cone of fire is tighter at every point in the firing sequence, but the rate at which the spread recovers after firing is unchanged. This distinction means that grip Spread reduction is most impactful on weapons with wide hip-fire spreads (shotguns, SMGs, LMGs) where the reduction in the maximum spread cap produces a noticeable tightening of the cone. On weapons with already tight hip-fire spreads (precision rifles, sniper rifles), the Spread modifier produces a smaller absolute change and the Recoil_X and Recoil_Y fields have more perceived impact.

Grip attachments on two-handed weapons

Two-handed weapons (weapons with the TwoHanded flag on the gun asset) support grip attachments identically to one-handed weapons. The Hook_Grip position on a two-handed weapon prefab should follow the same guidelines: underside of the fore-end or handguard, Y axis pointing downward. The two-handed weapon's broader fore-end typically provides more room for Hook_Grip placement, which can accommodate larger grip prefabs (such as a full-length bipod) without visual clipping.

Negative stat modifiers on grips

All four stat modifier fields (Recoil_X, Recoil_Y, Spread, Sway) accept values above 1.0, which produce a negative effect on the weapon's behavior. A grip with Recoil_X 1.20 increases horizontal recoil by 20 percent, making the weapon less stable. This is a valid design tool for cursed attachments, downside-trade-off items, or roleplay-specific grip designs where the visual weight of a large grip should penalize weapon handling. The Bipod flag gates negative modifiers in the same way it gates positive ones: for a bipod with Recoil_X 1.20, the increased recoil only applies while prone.

Pro variant grip attachments

The Pro flag on a grip attachment enables the item for the Pro variant drop pool. Pro variants are cosmetic-enhanced versions of standard items that appear in a dedicated loot tier on maps that support Pro drops. The Pro flag does not change any of the grip's stat modifier values -- the Pro variant uses the same Recoil_X, Recoil_Y, Spread, and Sway fields as the standard version. The only difference is the visual appearance, which is driven by the Pro variant's separate material assignment in the master bundle. If the mod design calls for a Pro variant with different stat values, the modder must author a separate grip attachment with a different ID and the desired stat modifier values; the Pro flag alone does not provide stat differentiation.

Grip attachment balance tuning methodology

The 57 Studios™ cohort has developed a structured methodology for tuning grip attachment balance that produces consistent results across different weapon classes. The methodology is based on the observation that the perceived effectiveness of a grip attachment depends on the weapon's base recoil profile, fire rate, and engagement range, not just on the grip's stat modifier values in isolation.

Step 1 -- establish the weapon's unmodified baseline. Fire the weapon without any grip equipped and record the vertical displacement over a full magazine in pixels or centimeters on the screen. For an assault rifle firing 30 rounds, the total vertical displacement at 30 meters range is the baseline measurement. Record the hip-fire cone diameter at the same range by measuring the spread of impacts on a flat target.

Step 2 -- define the target reduction percentage. Decide how much of the weapon's recoil and spread the grip should eliminate. For a standard vertical foregrip, the target is typically 15 to 20 percent reduction in both horizontal and vertical recoil. For a bipod, the target is typically 40 to 50 percent reduction, but only when prone.

Step 3 -- calculate the stat modifier values. Convert the target reduction percentage into a multiplier. A target of 20 percent reduction equals a multiplier of 0.80. A target of 45 percent reduction equals a multiplier of 0.55. The formula is multiplier = 1.0 - (target_percentage / 100).

Step 4 -- apply the grip and test. Equip the grip on the weapon and repeat the baseline measurement from Step 1. The measured reduction should match the target within a 5 percent tolerance. If the measured reduction is lower than the target, the grip's modifier is too weak and should be adjusted downward. If the measured reduction is higher than the target, the grip's modifier is too strong and should be adjusted upward.

Step 5 -- playtest with the grip in combat scenarios. The measured reduction from Step 4 may feel different in actual combat than on a stationary target test. A grip that reduces recoil by 20 percent on the test range may feel insufficient in a moving combat scenario where the player is strafing and tracking a target. The cohort recommendation is to adjust the grip's values by an additional 5 to 10 percent after playtesting if the combat feel does not match the design intent.

Grip attachment visual design considerations for the prefab

The grip attachment's prefab model should follow the weapon's visual design language while remaining clearly identifiable as a grip. The 57 Studios™ cohort has validated the following polygon budget and design guidelines for grip prefabs based on the vanilla grip geometry and the typical camera distance in Unturned™ gameplay.

Polygon budget: A standard vertical foregrip should target 200 to 600 triangles. A bipod is more complex due to the articulated leg geometry and should target 600 to 1500 triangles. Angled foregrips and stub foregrips fall within the 200 to 600 triangle range. Exceeding these budgets produces a grip that contributes unnecessarily to the bundle's draw call count without a visible improvement in quality at typical gameplay zoom levels.

Texture resolution: Grip attachments should use 512 by 512 pixel texture maps. The grip occupies a smaller portion of the screen than the weapon itself, and 512 by 512 provides sufficient detail for the visible surface area. Bipods with engraved or detailed leg geometry may benefit from 1024 by 1024 for the leg textures, but the main body should remain at 512 by 512 to keep the bundle size manageable.

Material assignments: Grip attachments should use the same shader as the weapon they attach to for visual consistency. The cohort-recommended weapon shader for Unturned™ supports metallic, roughness, and normal map channels. The grip's metallic values should match the weapon's construction material -- a polymer foregrip should use lower metallic values (0.0 to 0.3), while a metal bipod should use higher metallic values (0.6 to 0.9) to match the weapon's finish.

Localized grip names and descriptions

Each grip attachment must have an English.dat file in the same folder as its Asset.dat. The English.dat provides the display name and description that appear in the player's inventory tooltip. For Workshop mods targeting an international audience, the cohort recommendation is to author localization files for the languages the mod targets following Unturned™'s localization naming convention (French.dat, German.dat, Spanish.dat, Russian.dat, SimplifiedChinese.dat). Unturned™ selects the appropriate localization file based on the player's game language setting and falls back to English.dat when no matching localization exists.

Grip attachment testing workflow

The following end-to-end testing workflow ensures that every grip attachment field behaves as intended before the mod is published. The 57 Studios™ cohort has validated this workflow against the most common grip authoring failures.

Phase 1: field verification (pre-bundle)

Before building the master bundle, verify every field in the .dat file against the field reference table in this article. Confirm that Type Grip is present, Slot None is set, Caliber 0 is correct for universal grips or matches the intended weapon's caliber for restricted grips, and all stat modifier fields carry the intended values. Check that the Bipod flag is present on bipod-confirm grips and absent on non-bipod grips. Verify that Aiming_Movement_Speed_Multiplier is either omitted (for standard grips) or set to the intended movement penalty (for weighted grips).

Phase 2: prefab and bundle verification

Open the Unity project containing the grip prefab. Confirm that the prefab's root transform has a scale of 1, 1, 1 and that the mesh pivot point is at the attachment interface (the top of the grip, where it meets the weapon). Assign the material and confirm the shader is the correct weapon shader for Unturned™. Build the master bundle and copy the .unity3d file to the mod's Bundles/ folder alongside the .dat and English.dat files.

Phase 3: single-player visual test

Launch Unturned™ in single-player mode. Spawn the grip attachment using @give <ID>. Spawn a weapon that supports the Grip slot (a weapon with the Grip field in its .dat). Equip the grip by dragging it from the inventory to the weapon's Grip slot in the attachment panel. Confirm that the grip's 3D model appears at the correct position on the weapon with no clipping, floating, or rotation errors. If the grip is invisible, check Hook_Grip existence and casing in the weapon prefab. If the grip appears at the wrong position, adjust the hook's local position in Unity and rebuild the bundle.

Phase 4: single-player statistical test

Fire the weapon with the grip equipped at a stationary target (a spawned zombie, a placed barricade, or a free-aim point on a wall). Observe the recoil pattern. Compare it to the same weapon fired without a grip equipped. The difference should be perceptible but not extreme. For a vertical foregrip with Recoil_Y 0.80, the muzzle should climb approximately 20 percent less over a 30-round magazine than when no grip is equipped. If the recoil pattern is unchanged, confirm that the Recoil_X or Recoil_Y values in the .dat are below 1.0.

Phase 5: bipod posture test (bipod grips only)

For grip attachments carrying the Bipod flag, test the grip's behavior in each player posture. Fire the weapon while standing -- the recoil pattern should match the unmodified weapon because the Bipod flag suppresses all stat modifiers in the standing posture. Crouch and fire again -- same result, no modifier application. Go prone and fire -- the recoil pattern should show the full reduction from the grip's stat values. Stand up again and confirm that the modifiers stop applying immediately. This test is the single most important validation step for any bipod-equipped grip attachment because it confirms that the prone-only gating works as intended and that no unexpected modifier application occurs in the wrong posture.

Test sequence for bipod grip:
  1. Spawn gun and bipod grip.
  2. Equip bipod on gun.
  3. Fire standing       → observe full recoil (modifiers inactive).
  4. Fire crouching      → observe full recoil (modifiers inactive).
  5. Fire prone          → observe reduced recoil (modifiers active).
  6. Stand up and fire   → observe full recoil again (modifiers deactivate).

Phase 6: caliber restriction test (caliber-restricted grips only)

For grip attachments with a non-zero Caliber field, test the grip on a weapon with a matching caliber and on a weapon with a non-matching caliber. The grip should equip on the matching weapon and be rejected by the non-matching weapon (the attachment slot will refuse the item with no error message). If the grip equips on a weapon with a different caliber, the field value or the comparison logic is incorrect. This test is only relevant for caliber-restricted grips; universal grips (Caliber 0) pass this test by design on every weapon.

Phase 7: published-state verification

After the grip mod passes all single-player tests, install it on a dedicated server (local or remote) and repeat phases 3 through 5 in the multiplayer environment. Some grip behaviors that function correctly in single-player may behave differently in multiplayer due to server-side recoil and spread authority. If the grip behaves correctly in both single-player and multiplayer, the mod is ready for Workshop submission.

Appendix A: Grip .dat field quick-reference card

Field	Type	Required	Default	Notes
ID	uint16	Yes	--	50000+ range recommended
GUID	uint128	Yes	--	Fresh GUID per item
Type	enum	Yes	--	Must be Grip
Name	string	Yes	--	Internal, no spaces
Rarity	enum	No	Common	Common through Mythical
Slot	enum	Yes	--	Must be None
Size_X	uint8	Yes	--	Inventory width
Size_Y	uint8	Yes	--	Inventory height
Caliber	uint16	Yes	0	0 = universal
Recoil_X	float	No	1.0	Horizontal recoil multiplier
Recoil_Y	float	No	1.0	Vertical recoil multiplier
Spread	float	No	1.0	Hip-fire spread multiplier
Sway	float	No	1.0	Idle weapon sway multiplier
Aiming_Movement_Speed_Multiplier	float	No	1.0	ADS movement speed multiplier
Bipod	flag	No	absent	Stat modifiers only apply while prone
Pro	flag	No	absent	Pro variant drop pool eligibility

Appendix B: Grip archetype comparison table

Archetype	Recoil_X	Recoil_Y	Spread	Sway	Bipod	Caliber	Typical size
Stub foregrip	0.95	0.95	0.95	0.95	No	0	1x1
Vertical foregrip	0.85	0.80	0.90	0.80	No	0	1x2
Angled foregrip	0.80	0.88	0.95	0.85	No	0	1x2
Weighted handguard	0.88	0.88	0.88	0.88	No	0	1x2
Bipod	0.60	0.55	0.70	0.50	Yes	0	2x3
Caliber-restricted grip	per design	per design	per design	per design	optional	custom	1x2

Appendix C: External references

Resource	URL	Notes
Smartly Dressed Games modding documentation	https://docs.smartlydressedgames.com/en/stable/	Official field reference for ItemGripAsset. Verify field names before shipping.
Unturned on Steam	https://store.steampowered.com/app/304930/Unturned/	Game changelog and update history.
Gun Mod Tutorial	/items/gun-mod-tutorial	Prerequisite weapon prefab authoring pipeline.
Attachment Slots: Sight, Grip, Tactical, Barrel	/items/attachment-slots	Slot-level overview; covers all four attachment types.
Barrel Asset Reference	/items/barrel-asset-reference	Companion barrel attachment reference.
Optic Asset Reference	/items/optic-asset-reference	Companion optic attachment reference.
Caliber Asset	/items/caliber-asset	Caliber linkage system; how the caliber integer gates attachment compatibility.
Magazine Asset Reference	/items/magazine-asset	Magazine-side caliber fields for reference.

Frequently asked questions

What happens if I set Recoil_X and Recoil_Y both to 0.0 on a grip?

Setting both recoil multipliers to 0.0 eliminates horizontal and vertical recoil entirely when the grip is equipped. Every shot fires as if the weapon had zero recoil, producing a perfectly stable point of aim with no muzzle climb and no horizontal kick. The 57 Studios™ cohort strongly advises against shipping a grip with 0.0 values in a publicly released mod because zero-recoil configurations produce an unfair gameplay advantage that damages server reputation and reduces the skill expression in weapon handling. If the mod design calls for a very stable grip, use values in the 0.60 to 0.75 range with the Bipod flag to gate the extreme stability behind the prone condition.

Can a grip attachment increase recoil instead of reducing it?

Yes. Setting Recoil_X, Recoil_Y, Spread, or Sway to values above 1.0 increases the corresponding statistic, making the weapon harder to control. A grip with Recoil_X 1.20 and Recoil_Y 1.25 produces a weapon that kicks 20 to 25 percent harder than its unmodified state. This is a valid design tool for cursed attachments, trade-off items that provide a non-statistical benefit (a grip with a built-in laser sight that uses the Tactical slot plus the Grip slot in a combined model), or roleplay items where the grip is cosmetic rather than functional. The Bipod flag gates negative modifiers in the same way it gates positive ones: a bipod with increased recoil only applies that increase while prone.

Does the Spread field affect aim-down-sights spread?

No. The grip's Spread field only affects the hip-fire spread (Spread_Hip on the gun asset). Aim-down-sights spread (Spread_Aim) is not modified by grip attachments. The sight attachment slot is the correct place to modify ADS spread through the Spread_Multiplier_ADS field on the sight .dat. If the mod design calls for a grip that also tightens ADS spread, the modder must accept that the modifier is applied to hip-fire only and document this limitation in the item description.

How does Sway differ from Recoil in gameplay feel?

Sway governs the weapon's resting motion -- the natural drift that occurs when the player is holding the weapon without firing. It is a continuous, low-frequency oscillation that the player experiences as breathing motion and muscle fatigue. Recoil_X and Recoil_Y govern the weapon's firing motion -- the sharp impulse that occurs with each shot. The distinction matters for balance: a grip with low Sway (e.g., 0.50) but unmodified Recoil_Y (1.0) produces a weapon that is steady at rest but climbs aggressively when fired. This is the behavior of a precision shooting grip that helps the player hold a sight picture but does not reduce the recoil impulse itself.

Why does my bipod grip not reduce recoil when I am standing?

The Bipod flag is present on the grip, which means all stat modifier fields (Recoil_X, Recoil_Y, Spread, Sway, Aiming_Movement_Speed_Multiplier) are gated behind the prone posture check. While standing, crouching, swimming, climbing, or riding in a vehicle, the engine ignores the grip's entire stat modifier block and the weapon behaves as if the Grip slot were empty. This is the intended gameplay behavior for bipods. If the design goal is a grip that reduces recoil in all postures but has aggressive values, remove the Bipod flag and reduce the stat values to the vertical foregrip range (0.80 to 0.90) rather than the bipod range (0.50 to 0.70).

Can I have two grips on the same weapon by using a different slot?

Yes, if a second grip attachment uses a different Type value (e.g., Tactical instead of Grip) and the weapon has a corresponding slot and hook for that type, the grip model will be positioned at the second slot's hook position. However, this is a visual-only workaround: the second attachment's stat modifiers (Recoil_X, Recoil_Y, Spread, Sway) are only applied if the attachment's Type value matches the slot it is occupying. A grip attached to the Tactical slot via the Type Tactical field will not have its Recoil_X field read by the engine because the engine reads recoil modifiers only from the Grip slot's attachment. The cohort recommendation is to accept the single-grip constraint rather than to attempt multi-slot workarounds that produce inconsistent statistical behavior.

What is the correct inventory size for a bipod?

A bipod in its folded or stored configuration occupies more inventory space than a standard vertical foregrip because the bipod's legs fold alongside the main body, creating a wider and taller inventory item. The cohort-validated sizes are Size_X 2 by Size_Y 3 for a full-size bipod that can be deployed from folded configuration. A compact bipod designed for carbine-length handguards can use Size_X 2 by Size_Y 2. The larger footprint is a meaningful inventory cost that offsets the bipod's aggressive recoil reduction: a player who carries a bipod in the inventory is spending three to four grid slots that cannot carry ammunition, medical supplies, or other attachments.

Does the grip's Spread modifier affect all weapon spread categories simultaneously?

No. The grip's Spread field specifically modifies the weapon's Spread_Hip value. It does not modify Spread_Aim, which is the spread value used when the player is looking through the weapon's sights. The Spread_Aim value is modified by sight attachments through the Spread_Multiplier_ADS field, not by grip attachments. This separation means that a player who fires from the hip with a grip-equipped weapon experiences tighter hip-fire spread, but a player who aims down sights with the same grip-equipped weapon experiences the weapon's unmodified Spread_Aim value. The 57 Studios™ cohort recommendation is to design grip Spread values with the understanding that they primarily benefit close-quarters hip-fire engagements, not precision aim-down-sights shooting.

Can a grip attachment have a negative Aiming_Movement_Speed_Multiplier value?

The Aiming_Movement_Speed_Multiplier field accepts any float value, including values that produce counterintuitive behavior. A value of 0.0 makes the player completely immobile while aiming down sights -- the player cannot move at all when ADS is active. A value above 1.0 increases the player's ADS movement speed above the weapon's base ADS speed, which produces an effect where the player moves faster with the grip equipped and ADS active than without it. Values below 1.0 but above 0.0 produce a gradual movement penalty, with 0.85 being a typical penalty for a heavy bipod or weighted handguard. The cohort recommendation is to keep this field in the 0.80 to 1.0 range; values below 0.80 produce an ADS movement penalty that most players experience as frustrating rather than balanced.

How does the grip's Sway modifier interact with the weapon's existing sway pattern?

The weapon's sway pattern is defined by the gun asset's internal sway parameters, which the SDG documentation does not expose as modifiable .dat fields. The grip's Sway modifier applies as a uniform multiplier across all axes of the weapon's existing sway motion. A weapon with a naturally circular sway pattern (the weapon drifts in a circular motion when held) will have that circular motion reduced in amplitude by the Sway multiplier. A weapon with an elliptical sway pattern (more horizontal drift than vertical drift) will have both axes reduced equally by the multiplier; the Sway field does not provide per-axis control. The effect is perceived as a general steadying of the weapon regardless of the underlying sway pattern's shape, making the grip Sway modifier one of the most universally beneficial grip fields across all weapon classes.

Does the Bipod flag affect the hook position or the grip prefab?

No. The Bipod flag is a purely statistical field that gates the application of stat modifier values. It has no effect on the visual model, the hook position, or the prefab hierarchy. A bipod grip prefab that has a deployed (legs extended) visual state in the prefab will show that visual state regardless of how the Bipod flag is set. The engine does not automatically switch between deployed and folded visual states based on the Bipod flag. If the mod design calls for a visual difference between the active and inactive bipod state, that switching must be implemented through an Animator Controller on the grip prefab that reacts to the player's posture, which is an advanced prefab authoring technique beyond the scope of .dat field configuration.

Authoring checklist

Before publishing a grip attachment mod to the Steam Workshop, confirm every item in the following checklist:

• [ ] ID is in the 50000+ range and does not conflict with any other loaded item in the project.
• [ ] GUID was generated fresh for this grip attachment and is not copied from another asset.
• [ ] Type Grip is present and spelled correctly.
• [ ] Slot None is set.
• [ ] Caliber 0 for universal grips, or a matching custom caliber for caliber-restricted grips.
• [ ] Recoil_X, Recoil_Y, Spread, and Sway are all set to intended values below 1.0 for beneficial grips.
• [ ] Bipod flag is present if the grip is a bipod; absent if it is a standard grip.
• [ ] Aiming_Movement_Speed_Multiplier is tuned as a balancing lever, or omitted for standard grips.
• [ ] English.dat is authored with Name and Description fields in the same folder as Asset.dat.
• [ ] The master bundle contains the grip prefab at the correct name matching the Name field.
• [ ] Hook_Grip exists in the weapon prefab with correct casing and positioning.
• [ ] The grip prefab's pivot point is aligned with the Hook_Grip origin for correct visual seating.
• [ ] Tested in single-player: spawn the grip with @give, equip on weapon, confirm visual and statistical effect.
• [ ] For bipod grips: tested prone and standing to confirm the posture gating works as intended.
• [ ] Caliber compatibility tested: confirm the grip equips on intended weapons and does not equip on unintended ones.
• [ ] Steam Workshop description documents the grip's behavior, including bipod-only activation if applicable.

Document history

Version	Date	Author	Notes
1.0	2026-07-26	57 Studios	Initial publication. Complete grip asset .dat field reference, Bipod flag mechanic documentation, caliber compatibility, worked examples, FAQ, balance reference tables, prefab hook placement guide, and authoring checklist.

Cross-references

• Barrel Asset Reference -- the previous article in the item reference series; covers the companion barrel attachment type with its Silenced, Braked, and Durability fields.
• Optic Asset Reference -- the next article in the item reference series; covers sight and scope attachments with the Zoom, Distance, and Holographic fields.
• Attachment Slots: Sight, Grip, Tactical, Barrel -- the slot-level overview of all four attachment types, including the Grip slot field table, the caliber compatibility flowchart, and the common mistakes diagnostic table.
• Caliber Asset -- the caliber linkage system reference; covers the distinction between the caliber integer used for attachment compatibility and the Caliber asset used for ballistic parameter definition.
• Magazine Asset Reference -- the magazine asset reference for the paired magazine system that grip attachments interact with indirectly through the caliber linkage system.
• Gun Mod Tutorial -- the prerequisite for building the weapon prefab with Hook_Grip and the supporting Unity pipeline.
• Master Bundle Export -- the packaging workflow for building the grip attachment's master bundle after the prefab is authored.
• Smartly Dressed Games modding documentation -- authoritative source for field names, enumeration values, and class hierarchy details.
• Unturned on Steam -- the game's Steam store page and community hub.