4.5in 22LR barrel
This 4140 Chrome Moly Steel barrel fits into Mil-Spec AR-15 upper receivers so you can shoot all day with little expense. All that is needed to finish the conversion is this barrel, a CMMG 22lr Arc bolt group, and a CMMG 22Arc magazine. This barrel also comes with a collar that lets you replace the chamber adapter that comes on the 22lr Arc bolt group. The sporting chamber offers more reliable function than the standard chamber. It is fully nitride inside and out to give it high corrosion resistance and longevity. This conversion gives you the benefit of the modularity of the AR-15 platform and ergonomics while saving money on ammo. The extremely short barrel length also makes a great compact carbine or pistol that can be easily stored away or hidden. It is also a great option for training people to use the AR-15 weapon system before moving them to the larger .223 cartridge.