Shaw Barrels PS90 5.7x28mm 10.4" 4140CM Nitride Barrel - M12x1 LH

The Shaw Barrels PS90 is a precision drop-in replacement barrel for the FN PS90 pistol-caliber carbine, chambered in 5.7x28mm. Cut from 4140 Chrome-Moly steel and finished in a wear-resistant salt-bath nitride coating, this barrel is the go-to upgrade for PS90 owners building a short-barreled-rifle configuration or refreshing a worn factory barrel.

The barrel measures 10.4" overall and weighs just 0.4 pounds, preserving the PS90's compact, balanced handling. A 1:9" twist rate reliably stabilizes the full range of 5.7x28mm projectiles, from lightweight high-velocity varmint loads to heavier defensive hollow points. Muzzle threads are cut M12x1 left-hand to accept PS90-pattern flash hiders and thread adapters.

Shaw builds this PS90 barrel in the USA to the same precision standards the company applies across its rifle and AR-platform barrels. The 10.4" length drops into the factory floating-barrel and barrel-nut system without modification, making it a straightforward swap for any qualified builder.