Nov 4, 2025

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.

Inventors: Frederick H. Kart
Filing date: 2024-02-16

firearmbarrelriflingblow-by

This patent describes a firearm barrel designed to reduce blow-by gases by incorporating rifling with a specific configuration of grooves and lands, including a reduced width component that forms an acute angle relative to the barrel’s longitudinal axis. The method outlined aims to prevent gases from escaping ahead of the bullet as it travels through the barrel, enhancing overall firearm performance.

Claim 1

1 . A method of preventing blow-by in a firearm comprising the steps of: providing a firearm barrel having a longitudinal axis, 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 and exiting a muzzle end; forming in each of the plurality of lands a reduced width component communicating with the chamber end of the barrel for a predetermined distance towards the muzzle end of the barrel, wherein the reduced width component defines an acute angle in relation to the longitudinal axis of the barrel; and preventing blow-by from exiting the barrel in advance of the bullet via the reduced width component, wherein the firearm barrel includes a 0.125 inch throat, a 0.030 inch space from the chamber end of the barrel to the lands; 0.200 inch between lands at a distance of 0.125 inch from the end of the chamber, a land width of 0.040 at 0.125 inch from the end of the chamber and a groove width of 0.200 inch at 0.125 inch from the end of the chamber. providing a firearm barrel having a longitudinal axis, 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 and exiting a muzzle end; forming in each of the plurality of lands a reduced width component communicating with the chamber end of the barrel for a predetermined distance towards the muzzle end of the barrel, wherein the reduced width component defines an acute angle in relation to the longitudinal axis of the barrel; and preventing blow-by from exiting the barrel in advance of the bullet via the reduced width component, wherein the firearm barrel includes a 0.125 inch throat, a 0.030 inch space from the chamber end of the barrel to the lands; 0.200 inch between lands at a distance of 0.125 inch from the end of the chamber, a land width of 0.040 at 0.125 inch from the end of the chamber and a groove width of 0.200 inch at 0.125 inch from the end of the chamber.

Google Patents

https://patents.google.com/patent/US12460886

USPTO PDF

https://image-ppubs.uspto.gov/dirsearch-public/print/downloadPdf/12460886