GB1377750A - Firearms - Google Patents

Abstract

1377750 Projectiles; firearm barrels J R MANIS 17 Nov 1971 [18 Nov 1970] 53316/71 Headings F3C and F3A A firearm barrel 11, Fig. 1, has a number of gas-relief chambers 10 formed in its bore 12 so that, when a projectile 14 passes therethrough helical notches 16 formed on the projectile 14 re-act with the chambers 10 to effect rotation of the projectile. The chambers 10 may be replaced by staggered rows or pockets 25, Fig. 3, the barrel may be lubricated, during the passage therethrough of the projectile, by lubricant stored in the cannelure of the projectile 49, Fig. 7, and forced through apertures 48 of a jacket 46 mounted on the projectile. The barrel may be provided with a false barrel 57, Fig. 3, an air space 63 between the barrels 30 and 57 allowing the latter to propagate and dissipate sound wave energy in the form of vibration. Helical grooves may extend from a tapered heel 34 of a projectile as shown in Fig. 9, may extend from a flat end of a projectile as shown in Fig. 10, and may be formed on the jacket 46, Fig. 7.