Gerlich_principle
Squeeze bore
Weapon type
A squeeze bore, alternatively taper-bore, cone barrel or conical barrel, is a weapon where the internal barrel diameter progressively decreases towards the muzzle resulting in a reduced final internal diameter. These weapons are used in conjunction with special sub-caliber ammunition where the projectile is fitted with soft-metal flanges which fills out the caliber.[1] As the projectile travels through the squeeze bore the flanges fold inwards, resulting in a reduced caliber round with an increased velocity compared to a traditional full-caliber round.[1]