M*CARBO Brotherhood

.223 to .22LR Conversion Kit

I am thinking of getting the CMMG Bravo 22LR AR-15 Conversion Kit 5.56/.223 to .22LR, somebody out there want to talk me out of it. :confused: I’ll be using a Ruger AR 556 . Thanks for any input from the Brotherhood.


I don’t have experience with the conversion kit, but … I wonder about your 223 barrel’s twist rate. 22lrs generally twist once in 16". Once in 7", 8" or 9" is typical for .223, so let’s settle on twice as fast.

Now the typical 22lr pill has less engagement of the rifling than .223, and I believe the lead is also softer than the copper or steel jacket of .223. I would expect leading. I would not expect “good” accuracy.

I’d look hard at building a dedicated 22lr upper or buying a 22lr AR15. I started looking at the conversions and stalled when I decided the twist rate was too far off for my tastes. Then I stumbled across a M&P 15-22 for under $300 and … I bought it for my gf’s son and he’s been plenty happy.


@Dred Thanks for the input. The company says they recommend 36 grain plated nose bullets . I will take a look at the M&P.


I’d grab this:

22lr Colt M4


@dred I will look into it. Thanks for your time on this.:+1:


I have one and found it et o be great fun. I use any old bulk ammo various grains. Shots about 2 inches low on my iron sights. Great fun for AR but if your looking for more accurate 22 then fo with dedicated
Mine ran 172.00 shipped with three mags.




Do it! We have the CMMG drop-in for our ARs, and there’s not a time we leave the range after shooting it that there’s not a big stupid grin on both our faces. It’s stupid-cheap fun.

It WILL shoot differently than your 223. Ours seems to shoot a bit low. But if you take that into account, you can make single ragged holes in the paper at 30 yds.

We got the conversion kit so we can use the M&P 15-22 magazines. That kit also features LRBHO. The CMMG will hold the bolt open on the last round, but it’s because the bolt impinges on the follower. When you eject the magazine, the bolt closes. The adapter drops in the mag well in about 2 minutes.

Do it!


Gene Beaird,
Pearland, Texas


@FoldedCarbine Thanks for the response on this. I I have a Ruger AR 556 and the kit won’t work with it. It has an open bolt carrier and the wrong type of hammer. I was one click away from ordering it , decided to call the company, CMMG , just to check and was given the bad news. Guess I will just have to get a dedicated 22. The quest goes on.

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Wow that is unfortunate.