In today’s world of ammo shortages and increased prices, CMMG’s .22 LR AR bolt conversion kit offers a budget-friendly alternative for those who want more trigger time with their AR-15 minus high ammo costs. The kit consists of a single-piece bolt system that replaces the standard AR-15 bolt and special magazines to load .22 LR.

Setting the whole thing up can be done in just a few seconds without the need for tools. The fortunate magic of the AR-15 platform is that a .223/5.56 NATO barrel is just close enough to the .22 LR caliber to allow it to function in the gun with relatively good accuracy at plinking distances. CMMG does offer dedicated .22 LR guns, and there’s a healthy number of .22 ARs on the market. Boasting barrels dedicated to .22 caliber, they have some advantages in accuracy and, likely, overall reliability. But there’s something to be said about a packable conversion pal for range days.

Why Grab A Conversion Bolt


CMMG .22 LR AR Bolt Conversion
The CMMG .22 LR conversion bolt simply replaces the standard AR-15 bolt. (Photo: Paul Peterson/

CMMG’s conversion bolt is hardly new, but the current ammo situation likely makes it more utilitarian than ever. Though, simply calling it a “bolt” conversion kit is slightly misleading given that the system is actually made up of an integrated bolt, recoil spring, chamber, and barrel insert.

One of the main advantages of using the CMMG bolt is that it allows you to stick with your preferred rifle. Your trigger, sights, grip, and accessories can all stay exactly the same. Even the weight difference is barely noticeable, with the CMMG bolt coming in at 9.7 ounces compared to 11.1 ounces for something like a common M&P15 Sport bolt. So you can worry less about training scars during high-volume shooting sessions. 

CMMG .22 LR AR Bolt Conversion
The bold system slides right into your mil-spec AR upper. (Photo: Paul Peterson/
CMMG .22 LR AR Bolt Conversion Magazine
CMMG .22 LR mags feed the bolt system. (Photo: Paul Peterson/

Plus, I’ve personally found the conversion to be plinking accurate to about 50 yards with steel silhouettes and no adjustment to my sights. If you wanted to stretch its legs to greater distances, you’ll have to fight the ballistics differences between .22 LR and .223/5.56 and the fact that the barrel is not exactly .22 caliber.

CMMG .22 LR AR Bolt Conversion
The conversion bolt replaces the .223/5.56 chamber with a .22 insert. (Photo: Paul Peterson/
CMMG .22 LR AR Bolt Conversion
The bolt portion of the conversion kit slides while leaving the chamber interface in place. (Photo: Paul Peterson/

While the bolt certainly makes extended training with your AR-15 far less cost prohibitive, it also opens new plinking doors for those who don’t want to destroy their steel targets with high-velocity .223/5.56 rounds. In fact, one of my favorite plinking ranges limits shooting to .22 LR, making the CMMG a nice companion for some steel-target fun.

Calling it a companion is appropriate, and I like to stuff my CMMG bolt into my range kit when I head out with my ARs as a way to extend my shooting visits when I’ve exhausted my allowance of .223/5.56 for the day. If I happen to have more time on the range, I also have a small package that will deliver plenty more shooting time.

A Few Limitations


CMMG .22 LR AR Bolt Conversion
As a .22 LR conversion, there are some limitations. (Photo: Paul Peterson/

It helps that the CMMG kit can be had for a lot less than many secondary, dedicated .22 ARs. It’s not a perfect substitute, mind you. For one thing, the bolt does not hold open in the same fashion that your AR-15 bolt will, so rapid mag changes are going to still require a slingshot of the charging handle. More to the point, the recoil impulse is certainly less with .22. That’s not all bad, and it might even help you get rid of that flinch when shooting if you have one. 

It's also worth remembering that you are entering the realm of .22 semi-auto rifles, so you will almost certainly have to deal some of the issues common to shooting a lot of .22 LR – occasional stove pipes and dirtier ammo. CMMG recommends you avoid using notched hammers and says you’ll likely get the best results with 36-grain plated-nose bullets. Lastly, there is no guarantee the kit will work in a .223 Wylde gun because it does not have a mil-spec chamber.

Still, it's all well worth the money in my book. After just a few range visits, the kit will basically pay for itself given the current cost of .223/5.56. Plus, all CMMG products come with a lifetime quality guarantee, not that I’ve had any issues to date with my personal bolt.

Read More On:
revolver barrel loading graphic