Abstract: A firearm includes a noise suppressor comprising ports in the barrel opening into an annulus provided between a barrel and a sleeve extending from adjacent the muzzle to adjacent the receiver. In the annulus are a series of baffles. The most upstream port opens upstream of the most upstream baffle and downstream ports open between adjacent baffles. In some embodiments, the upstream ports are considerably larger than the downstream ports. Propulsion gases escape from the barrel into the annulus before the projectile clears the muzzle. Sabot rounds or shotgun rounds can be safely fired in the weapon because the sabot carrier or shot cup don't begin to expand until it is past the muzzle end so it cannot damage the noise suppressor.

Abstract: An assembly for a firearm (10) includes a sleeve (22) connected to the receiver or receiver end of the barrel (18). The sleeve (22) extends beyond the discharge end of the barrel (18) and includes inwardly extending projections (42) abutting or juxtaposed to a peripheral section (44) of the discharge end of the barrel (18). A noise suppressor (24, 50) threads onto the sleeve (22). Some of the propellant gases are redirected and cooled by the noise suppressor (24, 50) in a conventional manner. Some of the propellant gases are redirected into an annulus (46) between the barrel (18) and sleeve (22) where they are cooled and some of their volume is reduced thereby increasing the efficiency of the noise suppressor (24, 50).

Abstract: An assembly for a firearm (10) includes a sleeve (22) connected to the receiver or receiver end of the barrel (18). The sleeve (22) extends beyond the discharge end of the barrel (18) and includes inwardly extending projections (42) abutting or juxtaposed to a peripheral section (44) of the discharge end of the barrel (18). A noise suppressor (24, 50) threads onto the sleeve (22) . Some of the propellant gases are redirected and cooled by the noise suppressor (24, 50) in a conventional manner. Some of the propellant gases are redirected into an annulus (46) between the barrel (18) and sleeve (22) where they are cooled and some of their volume is reduced thereby increasing the efficiency of the noise suppressor (24, 50).