I have been wanting to either get a dedicated .22LR AR or one of these kits for a while. I figured either would be a great way to introduce my wife and kids to AR shooting without the very loud report of the .223 that might otherwise scare them off. I had been keeping my eyes open for one or the other when I stumbled upon this kit at a recent gun show I attended. The price was right (far less than half of the price of a dedicated .22LR AR) so I grabbed it.

The front end of the CMMG kit replicates the shape of a .223/5.56 cartridge casing and functions as a short section of barrel before the round reaches the actual barrel. The kit functions on straight blowback operation and is completely self-contained. The spring and buffer in your AR get some time to rest when using this kit as the small spring visible at the rear of the device is the actual recoil spring. The device appears solid and well-constructed. Mine came with one 25 round magazine that also appears solidly made.

I hung some clean paper and set myself up at about 45-50 yards. I fired two rounds of .223 to check and see where I was printing. Next, I installed the kit and fired five rounds of .22LR. I was pleasantly surprised by the results. There was a shift, but nothing drastic. All of the .22LR rounds struck within two and a half inches of the .223 impacts. If I were a sniper or planned on taking head shots, this would concern me, but since my plans for this kits consist of just putting rounds on paper and steel, this minimal shift is more than acceptable.

Video

Converting from .223 to .22LR takes only a few seconds. There are no permanent modifications required of the rifle, and all of the controls work as they should with only one exception, the factory bolt-catch does not work with the kit, but it also does not interfere with it. The video below shows me firing it both calibers and converting in between so you can see how quick and easy it is. While it functioned perfectly in my home built Frankenstein DI rifle, I am curious to see how well it will work in my piston operated LWRC. I will be bringing that home from work this weekend (my weekend which is most people’s work week) and will add an update to let you know if there are any compatibility issues with it.

Overall, this CMMG kit is a great value. It costs hundreds less than a dedicated .22LR AR, allows you to train with your rifle for pennies on the dollar where ammo is concerned, point of impact shift is negligible, it is well made and has been 100% reliable thus far. If you have been debating on which way to go (drop-in or dedicated .22), or have been wondering if these CMMG kits are worth what they charge, I would have to reply with an unequivocal yes.