Rifling

US12460886 - Reducing blow-by in firearms

A firearm barrel, including rifling formed of an alternating, spirally-extending plurality of grooves and lands defining a twist angle adapted for imparting rotation to a bullet being impelled through the barrel from a chamber end to and exiting a muzzle end. The plurality of lands each include a reduced width component communicating with the chamber end of the barrel for a predetermined distance towards the muzzle end of the barrel. The reduced width component defines an acute angle in relation to a longitudinal axis of the barrel adapted to cause a bullet being fired from the firearm to prevent blow-by gases to exit the barrel in advance of the bullet. A method of forming the firearm and barrel is also disclosed.