T91 Assault Rifle
- Category
- Assault Rifle
- Barrel
- 406 mm
- Weight, empty
- 3.17 kg
- Introduced
- 2003
About
What it is, and why it matters
The T91 is a Taiwanese gas-operated, selective-fire assault rifle chambered in 5.56x45mm NATO. Developed by the 205th Armory and introduced in 2003 as a successor to the T86 and T65 family, it uses a short-stroke gas piston system derived from the AR-18 lineage paired with an AR-15-style fire-control group and STANAG magazine compatibility. It features a collapsible stock, Picatinny rail for optics, and serves as the standard service rifle of the Republic of China (Taiwan) Armed Forces.
The T91 is the standard-issue rifle of Taiwan's armed forces and a centerpiece of the island's indigenous small-arms program, succeeding the T65 and T86 in frontline service.
The T91 evolved the earlier T65/T86 lineage with improved ergonomics, a flat-top receiver, and a quieter, more reliable short-stroke piston action. A shorter-barreled CQC carbine variant (349 mm barrel) serves special operations and vehicle crews.
Specification
Everything measured
IdentityWhat it is, who built it and when.
- Manufacturer
- 205th Armory
- Category
- Assault Rifle
- Country
- Taiwan
- Status
- In production
- Produced
- 2003
DimensionsAs issued, without a magazine or an optic.
- Barrel
- 406 mm
- Overall length
- 880 mm
- Weight, empty
- 3.17 kg
ActionHow it cycles, what trips it, and what feeds it.
- Action
- Gas operated
- Firing mechanism
- Hammer fired
- Trigger
- Single action
- Capacity
- 30
- Magazine
- Detachable box
MaterialsEach swatch is the material itself, not a colour chosen to stand for it.
- Frame
- Steel
- Barrel
- Steel
- Stock
- Polymer
- Finish
- Phosphate
BallisticsFrom the service cartridge, not a handload.
- Muzzle velocity
- 975 m/s
- Effective range
- 400 m
- Rate of fire
- 825 rpm
Trajectory
What the round does downrange
Solved from the muzzle figures and the bullet. The dashed rule is the effective range on the record, and the crosses are the steps the solver returned.
Features
What it has
What the record lists as fitted, drawn from the catalogue.
Collapsible stock
Picatinny rail
Ambidextrous controls
Short stroke gas piston
Stanag magazine compatible
Standing
How it compares
Each figure against the firearms of the same type and cartridge that record it, or of the same type where that cartridge has too few. Positions are read to the nearest tenth.
| Measurement | This firearm | Median | Position |
|---|---|---|---|
| Empty weightAmong 158 5.56x45mm NATO assault rifles | 3.17 kg | 3.60 kg | Lighter than about 80% |
| Overall lengthAmong 156 5.56x45mm NATO assault rifles | 880 mm | 920 mm | Shorter than about 60% |
| Barrel lengthAmong 157 5.56x45mm NATO assault rifles | 406 mm | 449 mm | Shorter than about 70% |
| Magazine capacityAmong 158 5.56x45mm NATO assault rifles | 30 | 30 | Near the median |
Answers
Questions about the T91 Assault Rifle
How much does the T91 Assault Rifle weigh?
The T91 Assault Rifle weighs 3.17 kg (6.99 lb) empty.
What caliber is the T91 Assault Rifle?
The T91 Assault Rifle is chambered in 5.56x45mm NATO.
How many rounds does the T91 Assault Rifle hold?
The T91 Assault Rifle holds 30 rounds, fed from a detachable box magazine.
How long is the T91 Assault Rifle?
The T91 Assault Rifle is 880 mm (34.6 in) long overall, with a 406 mm (16.0 in) barrel.
Who makes the T91 Assault Rifle?
The T91 Assault Rifle is made by 205th Armory (Taiwan). It was designed by 205th Armory.
When was the T91 Assault Rifle introduced?
The T91 Assault Rifle was introduced in 2003.
How does the T91 Assault Rifle operate?
The T91 Assault Rifle uses a gas operated action, and its firing mechanism is hammer fired.
Compatibility
Which parts fit this firearm
Studio
Every part that mounts on this, resolved
Not a list the maker typed out: the answer comes from the mounts this firearm exposes and the interface each part needs, so it stays right when either one changes.
- Every part that mounts on any firearm in the catalogue
- Interface standards, platforms and fit overrides
- The same answers through the API and the MCP server
Requires a signed-in GunSpec account on the Studio plan. The answer is computed per part, so it is not part of the public record.
Provenance
What the record holds
Every figure above was taken from one of these pages. The confidence reflects how much of the record came from a page a claim can be checked against.
In service
- Republic of China Armed Forces
- 2003
- Armed Forces of Bosnia and Herzegovina
- Bosnia & Herzegovina
Provenance
Confidence in this record
82%
Stockists
Where to buy
Offers link straight to the shop. GunSpec never takes the order.
No shop has listed this firearm yet
Stock and prices come from the shops themselves. If you sell this firearm, you can list it and it appears here.
List a firearmMCP
Ask an assistant about it
The same record, reached the way a person asks for it rather than the way a program does.
Ask GunSpec
Works with
Point an MCP client at GunSpec and it answers from the catalogue rather than from memory. A free key covers the read tools.
API
The call that returns this record
The same fields, in the same units, from the same endpoint the page reads.
curl --request GET \ --url 'https://api.gunspec.io/v1/firearms/t91-rifle' \ --header 'X-API-Key: your_key'{ "id": "t91-rifle", "name": "T91 Assault Rifle", "manufacturer": { "id": "205th-armory", "name": "205th Armory", "countryCode": "TW", "foundedYear": 1945, "website": null, "logoUrl": null, "description": null, "status": "active", "defunctYear": null, "stateOwned": true, "makesFirearms": true, "parentId": null, "predecessorId": null, "createdAt": "2026-04-05 22:24:37", "updatedAt": "2026-04-05 22:24:37", "version": "1256c35bd373f609ccaeff7942f3b8df63e8b0097f5c468fbba95344db513e5c" }, "category": { "id": "assault-rifle", "name": "Assault Rifle", "description": "Selective-fire rifles chambered in intermediate cartridges" }, "country_of_origin": "TW", "year_introduced": 2003, "barrel_length_mm": 406, "weight_empty_g": 3170, "action_type": "gas_operated"}