CMMG 22lr bolt question

[jhyan]

Is the bolt carrier on this...


the same as this...


just with an additional piece (breech adapter)? If so, can the adapter be removed? The first one can be had for about $25-$30 more than the second, if the piece is removable then it seems a cheap way to get three mags.

[gatx105]

The first is for a normal AR .223 upper, the second is for a .22 upper with a dedicated .22LR barrel. I think the fore ends can be switched, but it is more a part replacement, not just removing the adapter.

[jhyan]

I was planning on going with a true 22lr barrel attached to a normal AR upper, so I was looking at the second item. But if CMMG is just slapping a breech adapter on their bolt carrier to make it work with a normal 5.56 barrel, and I can pull that adapter off and use the bolt carrier without... I could save some money on mags.

[readysetgo]

What you're calling "breech adapter" is referred to as "barrel collar" here:

https://www.cmmginc.com/shop/barrel-collar-assembly-22arc-ss/

The first one is a bolt, barrel collar w/ adapter (intended for centerfire barrels) and mags.

You can use the first kit and leave out the barrel collar adapter IF your barrel is dedicated .22 WITH an existing collar.

Why don't you link us to/show us the barrel assembly you want to use?

[jhyan]

Thanks for the terminology correction, still learning here.

EDIT:

So, in order to use this item...

https://www.cmmginc.com/shop/bolt-group-22arc/

I can use this barrel, because the bcg comes with the right barrel collar

https://www.cmmginc.com/shop/barrel-sub-assm-16-1-m4-4140cm-sbn-22lr/

But to use this with a dedicated 22lr barrel like that above...

https://www.cmmginc.com/shop/22lr-ar-conversion-kit-bravo-w-3-10rd-magazines-grey/

I'd either need to pick up the barrel collar you linked to separately, or buy a barrel that comes with it like...

https://www.cmmginc.com/shop/barrel-and-collar-kit-16-1-m4-22lr/

Am i getting it now?

[Cokebottle]

I don't think they'll match up.

Notice the front edge of the assemblies.... the dedicated bolt is designed to slip over the built-in 22lr chamber, which is NOT an adapter that is removable from the barrel extension.

The conversion kit with magazines includes the entire adapter... even if removable, I don't think it will match up with the chamber in the dedicated upper.

[SonofWWIIDI]

Thanks for the terminology correction, still learning here.

EDIT:

So, in order to use this item...

https://www.cmmginc.com/shop/bolt-group-22arc/

I can use this barrel, because the bcg comes with the right barrel collar

https://www.cmmginc.com/shop/barrel-sub-assm-16-1-m4-4140cm-sbn-22lr/

But to use this with a dedicated 22lr barrel like that above...

https://www.cmmginc.com/shop/22lr-ar-conversion-kit-bravo-w-3-10rd-magazines-grey/

I'd either need to pick up the barrel collar you linked to separately, or buy a barrel that comes with it like...

https://www.cmmginc.com/shop/barrel-and-collar-kit-16-1-m4-22lr/

Am i getting it now?

You're first link is for a dedicated .22 barrel. So if you have a .223/5.56 barrel, use the other one.

[SonofWWIIDI]

My CMMG bolt and carrier for my dedicated .22 AR. .22 barrel and chamber.



Yes it's dirty, I use it frequently. Bugger off.

[readysetgo]

Thanks for the terminology correction, still learning here.

No worries, no snobbery intended on my part. I didn't know the name off hand but knew where to look and we needed to clear that up to understand correctly.

EDIT:

So, in order to use this item...

https://www.cmmginc.com/shop/bolt-group-22arc/

I can use this barrel, because the bcg comes with the right barrel collar

https://www.cmmginc.com/shop/barrel-sub-assm-16-1-m4-4140cm-sbn-22lr/

But to use this with a dedicated 22lr barrel like that above...

https://www.cmmginc.com/shop/22lr-ar-conversion-kit-bravo-w-3-10rd-magazines-grey/

I'd either need to pick up the barrel collar you linked to separately, or buy a barrel that comes with it like...

https://www.cmmginc.com/shop/barrel-and-collar-kit-16-1-m4-22lr/

Am i getting it now?

I'm saying yes, this exactly ^^^. Except the replies above make me doubt myself.

I don't have the centerfire adapter kit so can't say definitively. If you give me some time I'll go pull mine apart and illustrate my theory to be more sure. Or someone with more direct experience will chime in.

sondofwwiidi picture looks strange to me. I didn't think the barrel collar comes off with the bolt under normal use. Nevermind, they do normally "ride" together but it can be disassembled (more than just a field strip though). They are definitely two separate pieces though, the bolt/carrier and the barrel collar.

[readysetgo]

Here you can see the bolt broken down into it's sub components: https://www.cmmginc.com/product-cate.../22-arc-parts/

The collar for dedicated barrel is not there but I've already linked to that previously.

All those parts should be interchangeable. Note: IDK what the difference (if any) there is between the two bolts labeled "ARC" and "Bravo."

eta: Also check out: https://taccom3g.com
A good resource.

[jhyan]

I was assuming the brass piece and the silver tube came off, leaving behind the collar... but now I'm thinking the the brass piece and long silver tube are connected to the collar, and it's a different collar than the one on the dedicated bcg, thus the description on the item ... "Use this collar to convert your drop in kit to a dedicated bolt group"

[gatx105]

I would get the one already set for a .22 barrel, get the Redi-mag better mag adapter:
https://www.redi-mag.com/index.php?l...ct_detail&p=52 either from there or amazon.

It allows you to use the BHO feature and S&W M&P 15-22 magazines which i like more than the CMMG or black dog magazines. Yes its more expensive, but it allows your .22 AR to be more of a true trainer. Also with that combination I have had very minimal malfunctions, even compared to my 10/22's.

[Northerner]

they are both the same and interchange perfectly. the top one just has the case looking protrusion sticking out which goes into the standard .223 chamber and the bottom one locks around the dedicated .22 barrel.

i started with the top one when i built my AR and it shot good but i later bought the dedicated barrel and an upper and just needed to get the collar for the convertor and the rifle shot good before but after the barrel install it was night & day difference! shooting from a bag i could blow out dime size holes in paper from 25yds, and quarter size holes rapid fire.

you will not regret getting the convertor and a barrel, its a lot of fun shooting really tight groups!

(pics shows .223 upper and my CMMG .22 upper)

[readysetgo]

How did you remove the adapter? Is it just held on with that C clip in the first pic of OP?

[Cokebottle]

How did you remove the adapter? Is it just held on with that C clip in the first pic of OP?

Looks like everything forward of the extractor needs to be replaced.
See the parting line near the front?