Anyone ever try to put a CMMG dedicated collar on a old Jonathan Ciener 22 kit with chamber adapter oroginally? Thanks

I have used a CMMG collar on a Jonathan Arthur Ciener conversion bolt.   I think any of the JAC conversion kits for AR-15’s in 22 LR should work with either the CMMG .460” collar or the Spike’s,/TACCOM/Model 1 sales .500” collars.

The very early Atchisson 22 LR conversion kit might not work with the current collar.   The original Atchisson design went through some improvements/design changes before JAC started selling them.  

Try to be careful in spreading the guide rails just enough to roll the chamber insert off the guide rails.   The guide rails keep the alignment of the bolt and the tension on the chamber insert or collar.    For some reason my Ciener conversion would kick spent casings up and get stuck in the charging handle.   I usually needed needle nose pliers to dislodge the spent case.   If you encounter this problem the CMMG 22 rimfire charging handle or filling the groove in the centerfire charging handle will usually resolve the problem.

This topic is of interest to me. Would or should a RightToBear collar work ?

Yes they should work. RTB parts are made by CMMG.

Concerning cases getting stuck in the charging handle, there are three options.

1. Buy a dedicated charging handle from CMMG
2. Get a charging handle insert from Bore Buddy
3. Fill the void in the handle with RTV

I have done both 2 and 3 with good results. Yes an insert will last a lot longer than RTV but it is also real easy to reduce the RTV as needed.

I have option 1 in both of my .22 uppers.  Just made sense to me to buy the CMMG charging handles for 24/7 use being dedicated uppers.  For a conversion kit user that floats back and forth between .22lr and .223 the RTV mod or a borebuddy insert seems like just the ticket.

To answer the collar question I use the CMMG .460 and the Velocity .500 collar with an old Ciener bolt and their respective barrels all the time.  Works just fine.

Replace the weak extractor spring with a heavier tension spring.  It will eliminate the cases jumping off the bolt too early and getting jammed under the charging handle.  You should have positive 90 degree ejection of spent cases.

I found a CMMG collar for the Ciener..Only fired one 25 round mag through it, but it ran perfect..Thanks

Interesting,,
I have a dedicated 261 kit, would I need to use a collar or weight on it?

The CMMG/Ceiner Atchisson pattern is a different bolt design than the military M261 22 LR conversion kit.   Compass Lake Engineering is the only production 22 LR upper using the M261 bolt to my knowledge.  I know a gunsmith who fabricated his own dedicated 22 LR upper using an M261 Bolt.


The M261 conversion bolt uses a different recoils spring guide rod design compared to the CMMG plus the magazines are different for the M261 compared to the CMMG.

M261 Conversion kit photo




Here is a picture of a JAC conversion with chamber insert.