Question!!

Do I SBR my 15-22 or buy a dedicated upper .22lr upper for my SBR I already have?

Goal is to use 15-22 mags since we have a much of them laying around...

I was originally going to sbr my 15-22, but decided to use a lower that was already SBRed.  I used an adapter that allows a standard lower to accept 15-22 mags, and it runs great. Attached File

Do you have the name of the adaptors you used?  Great looking setup!

Redi-mag adapter

Here you go

I did the same as Oilfield Trash did... 9" CMMG upper with a Boonie Packer Better Mag adapter and 15-22 mags....

I went 4.5" deidctaed upper and I'm glad I did. It's neat to have a "real" AR .22lr setup with real parts, and I share my SBR lower with other uppers for now, I need to build a simple braced pistol lower as well to use when my SBR lower is in use elsewhere. (Plus I should be able to carry it in the truck loaded as a pistol in OK)

I hear the Redi-Mag adapter + MP-15/22 mags is the way to go, I'm planning to get one for mine.

A 4.5" 22LR with a suppressor under the hand guard and a red dot is pretty hard to beat for fun!

I agree with above, SBRing another standard AR lower is the way to go.

1. The S&W receiver is polymer
2. The S&W receiver has proprietary issues for changing things out (like the barrel nut and therefore the handguard)
3. The versatility and flexibility that a standard receiver has
4. If you already have a SBR lower you can get the short upper immediately and use it while waiting on the paperwork for the additional receiver


FWIW, I just went through this exact thought process last month. I ended up ordering a CMMG 4.5" barrel and bolt, a CMMG 22 charging handle, and the better mag adapter. I couldn't be happier - it makes a very nice setup.

I will definitely build a dedicated upper for a my SBR lower and form 1 another in the mean time...  Do the Redi-Mags insert into the lower or on top of the magazines?

it inserts from the bottom of the magwell and then a small second piece slides in around the bolt catch as the adapter comes up.

A spring loaded detent holds it in place while you swap mags.

It slides right back out for removal.

The standard mag catch holds the mags in place, the adapter just keeps the top of the mag in the proper position.