A device allows an AR-15 rifle, typically chambered for intermediate cartridges like .223 Remington or 5.56 NATO, to fire 9mm pistol ammunition. This usually involves replacing the rifle’s upper receiver, including the bolt carrier group and barrel, with components designed specifically for the 9mm cartridge. Often, these conversions necessitate using a specific magazine, like a Colt-style 9mm magazine, rather than the standard AR-15 magazine. Some conversion kits might also require a modified or dedicated lower receiver component, such as a magazine adapter or a different bolt catch.
Adapting an AR-15 platform to 9mm offers several potential advantages. The lower cost of 9mm ammunition compared to rifle cartridges makes high-volume practice more accessible. The reduced recoil of 9mm can improve controllability, especially for newer shooters. Furthermore, some shooters appreciate the compatibility with readily available handgun magazines. Historically, such conversions have appealed to those seeking a cost-effective way to train with the AR-15 platform or to have a versatile firearm capable of utilizing a more common and less expensive ammunition type. This adaptability has contributed to the enduring popularity of the AR-15 platform.
