Flint River Armory Introduces .45 ACP Carbine

Looking for a new pig gun? Flint River Armory of Huntsville, Ala, introduces the world’s first .45 ACP carbine that actually works: the CSA45. That’s because it’s the first .45 ACP carbine to feature a rotating/locking four-lug bolt and a 9mm short-stroke gas piston—designed from scratch.

The upper receiver is built from billet 6061 T-6 aluminum; the monolithic lower encompasses the buffer compartment; diagonal placement of the takedown and pivot pins provide structural strength. This may look like an AR—but it’s not! In fact, the only AR parts used on the CSA45 are an AR lower and a mil-spec fire-control system. The rest of the gun was designed from scratch by the folks at Flint River Armory, a company founded by a retired Navy aviator and staffed solely by engineers. The CSA45 is available as a carbine with a 16-inch barrel; as a short-barreled rifle with a 10-inch barrel; and as a pistol. Overall length of the carbine is 30 inches, and it weighs 6.7 pounds; SBR overall length is 24.9 inches, and it weighs 6 pounds; the pistol measures 24.5 inches and weighs 5.7 pounds.

Company staff tell us there is about as much design R&D put into the firearm’s proprietary, stainless steel, 25-round magazine as the rest of the gun, because it was a chore to design a double-stack, single-feed system that actually worked to feed .45 ACP cartridges. Flint River Armory tells us customers are reporting 1-inch groups at 50 yards from a bench. At least one load tested by the company includes Hornady Critical Defense (200-grain XTP bullet, 900 fps from the carbine).Color options are endless thanks to customer-chosen Cerakote finishes.