Weapon Customization (Workbench & Field)

Authoritative project content

Firearms can be customized with attachments, loaded like a Tarkov-style magazine/chamber loop, repaired, and (later) adjusted. All of this is server-authoritative. Core action times, jam chance, field repair, salvage yield, parts-only repair, magazine ammo whitelist, workbench interact range, and laser/light inputs are confirmed below. Stock-stat curves remain TBD-17D81164 (Phase 2+ / P21). Do not invent remaining catalog, kit identity, world-bench, or detection values.

Weapon dirt / fouling is cancelled (no dirt meter, no cleaning kit, no jam/spread-from-dirt). Melee blood stains are a separate visual system: 10-Blood-Visual.md.

Related: 03-Combat-System.md, 06-Inventory-and-Items.md, 07-Crafting-and-Progression.md, 05-Building-System.md, 10-Blood-Visual.md.

Phasing — [CONFIRMED]

Station — [CONFIRMED]

• Uses the same workbench as crafting. The station gains a firearm work mode (inspect / attach / adjust / repair) rather than a separate gunsmith deployable.
• Anyone nearby may use a placed workbench (no owner/clan lock for this interaction). Raiders can use a bench they find.
• Workbench is still a player-placed deployable (see 05-Building-System.md). World-placed benches are [TBD] and are not required for this feature.

Where actions happen — [CONFIRMED]

Install/remove does not require a tool item in the current design, whether performed in the field or at a workbench — [CONFIRMED].

TBD-16DB8041 — field repair — [CONFIRMED 2026-09-20]

Field repair is allowed. The acting inventory must hold equipment that supports repairing that item type: a gun repair kit, or matching family parts, for firearms. The loot-only kit identity is specified in TBD-8EF6FAED. The 10-second channel, cancellation, and kit-versus-parts exclusivity are the same in the field and at a workbench. Workbench interaction uses the same player interact as world-item pickup (IA_Interact / UInteractionComponent); do not author a second range.

Interruption — [CONFIRMED]

Timed bench (or field) actions are channels. If the player moves, takes damage, or dies, the channel cancels. Consumed time is lost; materials are not consumed (returned / never deducted).

• Install or remove a non-magazine attachment: instant — owner 2026-09-21. No channel and no stand-still requirement.
• Repair or salvage a firearm: 10 seconds.

Attachment slots — [CONFIRMED]

Phase 1 slot types:

Source 2026-09-21 adds ELambeerAttachmentSlot::Charm, default socket name CharmAttachment, persisted installed-state support and firearm/melee server validation. No charm Data Asset, weapon socket or compatibility pair was invented; those remain part of the attachment catalog. Underbarrel launchers / bipods are out of v1 slot list.

Compatibility — [CONFIRMED] rule, catalog [TBD]

Compatibility is by weapon family, not “any optic on any gun” and not a full rail-standard simulation.

[RECOMMENDATION] family list (replace with a real catalog when content exists):

• Pistol
• SMG
• Assault rifle (AR)
• DMR
• Shotgun
• Sniper

Every weapon and attachment Data Asset owns an explicit compatibility whitelist for allowed weapon families and/or exact item IDs — [CONFIRMED]. The server validates both sides of the pairing before installation. The L1810 pairings are confirmed content entries: LRD-01 (Optic), LS9-01 (Muzzle), LTL-100 (Laser), and Item.Magazine.L1810. Remaining weapon/attachment roster entries on those whitelists remain [TBD] under TBD-911C46EA. This is not the magazine-ammo list; ammo uses TBD-511DC680.

TBD-911C46EA — remaining attachment/weapon pairings

This decision is the rest of the which attachment mounts on which firearm catalog. It is not jam, repair, or magazine ammo. L1810 plus the three supplied accessories and the L1810 magazine are confirmed. Later guns and attachments still need their own Data Asset whitelist entries before they can install. Do not infer that an optic, suppressor, or light that fits L1810 fits every pistol.

Persistence & presentation — [CONFIRMED]

• Attachments are instance state on the weapon. They stay mounted when the weapon is dropped, looted, or left on a corpse.
• Equipped weapons show real attachment meshes. Other players see the same configuration (replicated).
• Workbench UI is a 3D inspect of the weapon (not a 2D slot grid as the primary UX).

Install/remove of a non-magazine attachment at the bench or in the field is instant and does not require or consume a tool item — [CONFIRMED 2026-09-21]. Combat magazine install/remove remains 3 seconds. Repair consumes either a kit or matching family parts as described below.

Magazines & ammunition (Tarkov-like) — [CONFIRMED]

• A magazine is an item that holds ammo. The player loads ammo into the mag; the mag is then installed on a compatible firearm.
• Loading and unloading ammo into/from a mag is done from inventory anywhere (no workbench required).
• Magazines do not stack. Each mag is its own instance with its own loaded rounds. That instance state persists with the item — [CONFIRMED 2026-09-14].
• Magazines may be partially filled (e.g. 15/30) and keep that count when stored, dropped, or left on a weapon.
• The player may unload a mag back into ammo piles/stacks.
• Mixed ammo types in one mag are allowed if each type is compatible with that mag. Canonical rule: TBD-511DC680.
• Mixed-ammo fire order: rounds are chambered and fired in the same order in which the player loaded them into the magazine. The first round loaded is the first round selected for chambering; the system preserves the per-round sequence and never groups or sorts by ammo type — [CONFIRMED].

TBD-511DC680 — magazine ammo whitelist — [CONFIRMED 2026-09-20]

A magazine accepts only ammunition ItemIds authored on the relevant DA_Item_* CompatibleItemIds lists. There is no implicit caliber/family fallback. Incompatible IDs cannot be inserted. Source 2026-09-20: LambeerMagazineRules::CanLoadAmmo and magazine install use either-side CompatibleItemIds only. Non-magazine attachments require both-sides whitelist. Head/Loop/Tail expansion is LambeerMagazinePlanRules; the workbench planner modal remains UI-SYS-006.

Field inspection inputs — [CONFIRMED 2026-09-08]

• Check chamber: IA_CheckChamber, Shift + R, action duration 3 seconds per firearm.
• Check magazine: IA_CheckMagazine, Alt + R, action duration 5 seconds per firearm.
• Combat magazine install: unmodified R, 3 seconds, right firearm then left. R replaces an already-installed mag. Movement is allowed. See FEAT-COMBAT.
• Press once to start; holding the keys is not required.
• When holding two firearms, inspect the right-hand firearm first, then the left-hand firearm — owner confirmed 2026-09-09. Total time is 6 seconds for chambers or 10 seconds for magazines.
• Owner confirmed 2026-09-09: An interrupted sequence does not retain newly collected inspection results, including the completed first firearm. Ammo/chamber truth comes from actual item data; do not impose empty defaults or use debug counts as production truth. Treatment of older observations predating the interrupted sequence remains unspecified.
• Only the completed corresponding check reveals that observed chamber/magazine state, following FEAT-HUD-UI. The existing field-action interruption contract remains applicable. [CONFIRMED 2026-09-14] Observed knowledge is client-only and is not saved. Every fired round clears chamber and magazine observation to UNKNOWN.

G3 source, 2026-09-10: Item.Weapon.L1810 used instance chamber/magazine counts (capacity 18, G3 new stacks full mag / empty chamber) so field checks did not require a magazine item. Firearm hand cards show Chamber/Mag knowledge even when the gun also tracks durability. HUD knowledge is applied only after the whole timed sequence finishes. Check Magazine uses the same Enhanced Input chord path as Check Chamber (IMC_Default R + IA_Alt). Owner reported Alt chord inspection on 2026-09-10. Debug UI_G3ObserveWeapon remains.

[CONFIRMED 2026-09-10 G3.2] New L1810 stacks spawn with no magazine and an empty chamber. Magazine-as-item rules in this document now apply: load/unload ammo from inventory anywhere (instant); install/remove magazine 3 s with no tool; removing a magazine can leave a chambered round. MCP created and saved DA_Item_L1810_Magazine / DA_Item_Ammo_9x19 on 2026-09-11. [OWNER-REPORTED PASS 2026-09-11] Owner reported load, 3 s install, move-cancel, unload and remove. See G3.2.

Chamber and bolt — [CONFIRMED] design

The firearm has a chambered round separate from the magazine, plus Tarkov-like handling:

• Check chamber
• Charge / rack
• Release bolt / bolt catch as applicable to the weapon

Removing the mag can leave one round in the chamber. Exact per-weapon bolt types (closed bolt, break action, etc.) remain [TBD] per firearm except L1810: [CONFIRMED 2026-09-20] closed-bolt semi-auto. A successful L1810 shot auto-chambers the next magazine round. Separate charge / rack / slide-lock controls are deferred. Combat reload key is R (3-second magazine install; dual firearms right then left). Presentation clip: /Game/Lambeer/Characters/Player/Animation/FirearmReload/A_PistolReload.

[RISK] This is high animation, audio, and input-surface cost. Keep it data-driven per weapon family so content does not require unique code per gun.

Laser / light — [CONFIRMED]

• Occupies the laser slot.
• Toggle on/off uses IA_TacticalDeviceToggle. Canonical names: TBD-D0682A36.
• Beam / IR or visible point is shown in the world; other players can see it.
• When on, it makes zombies more likely to detect / aggro the user. Exact detection bonuses are [TBD] under TBD-11668480. [CONFIRMED 2026-09-22] The P14 encounter slice does not apply this bonus. That slice uses sight and hearing only, per FEAT-ZOMBIE-DESIGN.

TBD-D0682A36 — tactical device inputs — [CONFIRMED 2026-09-20]

IA_TacticalDeviceToggle turns the mounted laser/light device on or off. IA_TacticalDeviceCycle cycles the on-state presentation; confirmed examples are LaserON/LightOFF and LaserON/LightON. Input Action assets exist at /Game/Lambeer/Core/Input/Actions/IA_TacticalDeviceToggle and IA_TacticalDeviceCycle. Character binds those actions. MCP readback 2026-09-21 of IMC_Default DefaultKeyMappings: toggle is unmodified T; cycle is Ctrl+T via InputTriggerChordAction on IA_Ctrl. BP_LambeerPlayerController already includes IMC_Default in DefaultMappingContexts. Do not invent extra cycle modes or keys.

Scope rail position — [CONFIRMED] (Phase 2+)

• Each firearm defines its own rail / mount points (count and spacing per weapon, not a global 2–3 preset).
• Adjustment is done only at the workbench.
• Effect is visual / ADS presentation only (eye relief, how the optic sits in ADS, perceived FOV/framing). It does not change combat numbers (damage, range falloff, spread, recoil). Firearm range damage drop is specified in FEAT-COMBAT.

Exact rail authoring (sockets vs spline) is an implementation detail; gameplay requirement is per-weapon mount positions.

Stock length — [CONFIRMED] (Phase 2+)

• Some stocks expose a continuous length slider (collapsed ↔ extended). Which stocks support it is per-item data.
• Adjustment is workbench-only.

• The slider does affect combat handling:

• Recoil / stability

• ADS speed / sway

• Mobility / ergonomics (move-while-aimed feel)

• Curves and magnitudes are [TBD]. Collapsed size / holster profile is not confirmed (do not implement concealment-size rules unless added later).

Durability — [CONFIRMED]

There is no dirt meter. Use still reduces durability. Blood on a firearm happens only if that gun is used to deal melee damage to a living target; it is visual-only (BloodAmount). See 10-Blood-Visual.md.

Durability is [CONFIRMED] for firearms and tools (including melee tools/weapons that use durability).

TBD-F2319BE6 — jam chance — [CONFIRMED 2026-09-20]

On an otherwise valid fire attempt, jam chance percent is 100 - DurabilityPercent / 2. Durability is the item’s 0–100 percent. Examples: 100 durability → 50% jam; 80 → 60%; 50 → 75%; 0 → 100%. Durability 0 already refuses fire, melee attack, and tool-role actions. Stock-stat curves stay TBD-17D81164.

Repair & salvage — [CONFIRMED 2026-09-20]

• A gun repair kit restores the target firearm to 100% durability in one completed 10-second repair action. The loot-only kit identity is specified in TBD-8EF6FAED.
• A firearm can be salvaged into family parts (e.g. break down an AR-family gun → AR parts). Yield is 1 + floor(DurabilityPercent / 20) — [CONFIRMED 2026-09-20] TBD-4AF8CE2A. Examples: 0–19% → 1 part; 20–39% → 2; 40–59% → 3; 60–79% → 4; 80–99% → 5; 100% → 6.
• Salvage consumes the donor weapon. Any mounted attachments are automatically removed and returned rather than destroyed — [CONFIRMED]. If the receiving inventory has no capacity, those attachments drop on the ground as runtime world drops and use the existing 24-hour remaining despawn in TECH-NETWORK-ARCH — [CONFIRMED 2026-09-20].
• Each repair action uses either one gun repair kit or matching family parts, never both. Kit and parts cannot be mixed in the same action — [CONFIRMED]. Parts-only repair: 1 part restores 15% durability in one completed 10-second action — [CONFIRMED 2026-09-20].

[CONFIRMED 2026-09-22] The Phase 2 Firearms skill reduces firearm spread/sway by 3% and firearm repair time by 2% per level above Level 1, reaching −27% spread/sway and −18% repair time at Level 10. It does not increase bullet damage or repair amount and does not gate Phase 1 install/remove. The canonical curve and rounding rules are in FEAT-CRAFTING-PROGRESSION.

Open questions still [TBD]

Do not implement as if decided:

• TBD-8EF6FAED — [RESOLVED 2026-09-22] Owner selected loot-only Gun Repair Kit for the first increment, with no crafting recipe. Planned ItemId: Item.Tool.GunRepairKit. Runtime Data Asset and loot-table authoring remain pending; no asset existence is claimed. The existing full-repair rule remains unchanged. Attach/remove still requires no tool item.
• Per-weapon rail socket lists and which stocks have a length slider (Phase 2+ / P21).
• Laser/light zombie detection bonuses (TBD-11668480). Out of the P14 encounter slice as of 2026-09-22.
• Whether world (non-player) workbenches exist (TBD-39DD8CFE).
• Remaining attachment catalog and family compatibility matrix beyond the confirmed L1810 pairings (TBD-911C46EA).
• Exact bolt types for firearms other than L1810 (TBD-6E2D4448).
• Stock-length combat curves (TBD-17D81164).