Gyrojet

Gyrojet
The Gyrojet carbine and rifle at the National Firearms Museum
TypeSmall arms (rocket launcher)
Place of originUnited States
Service history
WarsVietnam War
Production history
Designer
  • Robert Mainhardt
  • Art Biehl
ManufacturerMBAssociates
VariantsSee Variants
Specifications
Mass0.88 lb (0.40 kg)
Length10.88 in (27.6 cm)
Barrel length5 in (13 cm)

Cartridge
  • Mark I: 13 mm rocket
  • Mark II: 12 mm rocket
Caliber
  • Mark I: .51 caliber
  • Mark II: .49 caliber
ActionBlowback
Rate of fire
  • 60 RPM
  • Select fire (assault rifle variant)
Muzzle velocityVery low, but increasing over trajectory to about 1250 fps
Effective firing range55 yards (50 m)
Feed system6-round internal box magazine (main variants)
SightsIron sights

The Gyrojet is a family of unique firearms developed in the 1960s named for the method of gyroscopically stabilizing its projectiles. Rather than inert bullets, Gyrojets fire small rockets called Microjets which have little recoil and do not require a heavy barrel or chamber to resist the pressure of the combustion gases. Velocity on leaving the tube was very low, but increased to around 1,250 feet per second (380 m/s) at 30 feet (9.1 m). The result is a very lightweight and transportable weapon.[1]

Long out of production, today they are a coveted collector's item with prices for even the most common model ranging above $1,000. They are rarely fired; ammunition is scarce and can cost over $200 per round.[2]

  1. ^ "MBA Gyrojet Pistol". biskun.com. Archived from the original on April 12, 2010.
  2. ^ "Svenska Vapensamlarföreningen, SVEVAP - Gyrojet". svevap.se. Retrieved 2015-09-03.