INSAS 1B

Ordnance Factory Board · Assault Rifle · Discontinued · 1998

Also known as: INSAS Folding Butt Rifle, 5.56mm INSAS 1B, INSAS (Folding)

Overview

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.

Specifications

Weight (empty)4250 g (149.9 oz)
Weight (loaded)4730 g (166.8 oz)
Overall Length960 mm (37.80")
Folded Length750 mm (29.53")
Barrel Length464 mm (18.27")
Action TypeGas Operated Long Stroke
Firing MechanismHammer Fired
Trigger TypeSingle Stage
Magazine Capacity20 rounds
Magazine TypeDetachable Box
Muzzle Velocity900 m/s (2953 fps)
Muzzle Energy1620 J (1195 ft·lbf)
Effective Range400 m (437 yd)
Maximum Range700 m (766 yd)
Rate of Fire650 rpm
Barrel RiflingRight Hand
Rifling Twist178 mm (7.01")
Number of Grooves6
Frame MaterialStamped Steel
Barrel MaterialChrome Plated Steel
Stock MaterialSteel
FinishPhosphate

Calibers

Features

Variants

Base model

Insas

Service history

Operators

Conflicts

Production

Production years: 1998-2017

Produced alongside the fixed-butt INSAS at Ordnance Factory Board facilities; folding-stock version issued primarily to airborne and mechanised units

Origin

Country of origin: India

Designer: Armament Research and Development Establishment (ARDE)

Discontinued: 2017

Notes

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.

Background

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.