ALEXANDRIA, Va., Nov. 6 -- United States Patent no. 12,460,886, issued on Nov. 4.
"Reducing blow-by in firearms" was invented by Frederick H. Kart (Shallotte, N.C.).
According to the abstract* released by the U.S. Patent & Trademark Office: "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 ...