INSAS 1B
- Category
- Assault Rifle
- Barrel
- 464 mm
- Weight, empty
- 4.25 kg
- Introduced
- 1998
About
What it is, and why it matters
The INSAS 1B is the folding-stock variant of India's indigenously designed INSAS (Indian Small Arms System) assault rifle, developed by the Armament Research and Development Establishment (ARDE) and manufactured by the Ordnance Factory Board. Where the fixed-butt 1A rifle carries a solid polymer stock, the 1B is fitted with a side-folding tubular metal buttstock, making it the compact configuration favoured by paratroopers, mechanised infantry and vehicle crews. Chambered in 5.56x45mm NATO, it uses a gas-operated, long-stroke piston action with a rotating bolt derived from the Kalashnikov family, combined with a manual gas regulator (adapted from the FN FAL) for rifle-grenade launching and a left-side charging handle. The rifle fires from a closed bolt in semi-automatic and three-round burst modes at a cyclic rate of around 650 rounds per minute, feeding from translucent 20- or 30-round polymer magazines that allow a visual ammunition check. With a 464mm chrome-lined barrel it delivers a muzzle velocity near 900 m/s and an effective range of about 400 metres. The INSAS 1B served across the Indian Armed Forces from the late 1990s before being progressively replaced by the AK-203 and SIG716i.
The folding-butt INSAS was the version slung across the chests of India's paratroopers and Rashtriya Rifles counter-insurgency teams, its skeletal metal stock snapping shut for jumps and vehicle work. Yet the same rifle that symbolised indigenous defence pride at the 1998 Republic Day Parade was, a year later, jamming in the sub-zero heights of Kargil - a contradiction that would haunt the INSAS program until India turned to the Russian AK-203.
The 1B designation refers to the folding-butt rifle, distinct from the fixed-butt 1A and the later improved 1A1/1B1 models. Like the rest of the INSAS family the rifle drew criticism after the 1999 Kargil War for cold-weather jamming and cracked polymer magazines at high altitude, which drove the improved 1B1 revision. The standard rifle omits a fully automatic mode, offering only semi-automatic and three-round burst. Weight figures vary between sources (roughly 3.2-4.25 kg empty); the 4.25 kg value follows militaryfactory.com.
Specification
Everything measured
IdentityWhat it is, who built it and when.
- Manufacturer
- Ordnance Factory Board
- Category
- Assault Rifle
- Country
- India
- Status
- Discontinued
- Produced
- 1998 to 2017
- Variant of
- Folding stock
DimensionsAs issued, without a magazine or an optic.
- Barrel
- 464 mm
- Overall length
- 960 mm
- Weight, empty
- 4.25 kg
- Weight, loaded
- 4.73 kg
ActionHow it cycles, what trips it, and what feeds it.
- Action
- Gas operated long stroke
- Firing mechanism
- Hammer fired
- Trigger
- Single stage
- Capacity
- 20
- Magazine
- Detachable box
MaterialsEach swatch is the material itself, not a colour chosen to stand for it.
- Frame
- Stamped steel
- Barrel
- Chrome plated steel
- Stock
- Steel
- Finish
- Phosphate
BallisticsFrom the service cartridge, not a handload.
- Muzzle velocity
- 900 m/s
- Muzzle energy
- 1620 J
- Effective range
- 400 m
- Maximum range
- 700 m
- Rate of fire
- 650 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.
Gas operated rotating bolt
Long stroke piston
Chrome lined bore
Manual gas regulator- Gas cutoff for grenades
Side folding metal stock
Left side charging handle
Iron sights
Three round burst
Translucent polymer magazines
Bayonet lug
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 | 4.25 kg | 3.60 kg | Heavier than about 90% |
| Overall lengthAmong 156 5.56x45mm NATO assault rifles | 960 mm | 920 mm | Longer than about 70% |
| Barrel lengthAmong 157 5.56x45mm NATO assault rifles | 464 mm | 449 mm | Longer than about 70% |
| Magazine capacityAmong 158 5.56x45mm NATO assault rifles | 20 | 30 | Among the smallest capacities |
Answers
Questions about the INSAS 1B
How much does the INSAS 1B weigh?
The INSAS 1B weighs 4.25 kg (9.37 lb) empty and 4.73 kg (10.43 lb) loaded.
What caliber is the INSAS 1B?
The INSAS 1B is chambered in 5.56x45mm NATO.
How many rounds does the INSAS 1B hold?
The INSAS 1B holds 20 rounds, fed from a detachable box magazine.
How long is the INSAS 1B?
The INSAS 1B is 960 mm (37.8 in) long overall, with a 464 mm (18.3 in) barrel.
Who makes the INSAS 1B?
The INSAS 1B is made by Ordnance Factory Board (India). It was designed by Armament Research and Development Establishment (ARDE).
When was the INSAS 1B introduced?
The INSAS 1B was introduced in 1998 and discontinued in 2017.
How does the INSAS 1B operate?
The INSAS 1B uses a gas operated long stroke 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
- Indian Armed Forces
- 1998
- Indian Army Parachute Regiment
- 1998
- Nepalese Army
- 2001
Provenance
Confidence in this record
62%
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/insas-1b' \ --header 'X-API-Key: your_key'{ "id": "insas-1b", "name": "INSAS 1B", "manufacturer": { "id": "ofb", "name": "Ordnance Factory Board", "countryCode": "IN", "foundedYear": 1801, "website": "https://ddpdoo.gov.in", "logoUrl": null, "description": null, "status": null, "defunctYear": null, "stateOwned": null, "makesFirearms": null, "parentId": null, "predecessorId": null, "createdAt": "2026-02-18 03:40:45", "updatedAt": "2026-02-18 03:40:45", "version": "d58d313a90113a96514798866a97c2292f5297923579daab68ccc7924f6635b1" }, "category": { "id": "assault-rifle", "name": "Assault Rifle", "description": "Selective-fire rifles chambered in intermediate cartridges" }, "country_of_origin": "IN", "year_introduced": 1998, "barrel_length_mm": 464, "weight_empty_g": 4250, "action_type": "gas_operated_long_stroke"}