I got a CMMG 9mm PDW this morning.  Need to remove the standard pistol buffer tube to replace with a KAK Sig brace buffer tube.  What is the best way to remove it?  Are they lok-tited  down or staked in some fashion?  Need to know what I am dealing with here.  Thanks for any info.

Mine came off easy. No loctite or anything to hinder removal.

Ditto. Mine had No Loctite...

Dave in Florida

a liitle heat will fix it if it has thread locker.

Hmmm... mine is not moving.  Tried twisting by hand, bracing it, no go.   Tried heating it with a hair dryer til hot, nothing.  Put it in a vise a tried as much torque as I felt comfortable and still nothing.  Just coated it with penetrating oil and will let it sit til tomorrow.  I was hoping this was going to be easy...sigh.

You have a castle nut wrench?

OP, did you ever resolve?  I thought there would be a castle nut, but I gotta say it doesn't look that way in their picture:


FWIW, I've found CMMG's online tech support to be fantastic, so if you haven't already resolved this, give them a shout.

No, never got it off.  I decided to just do a makeshift solution of wrapping several layers of electrical tape to place the brace where I want it.



Right now, I am focusing on getting it to function reliably.  It jams quite often.  Getting a Spike's 9mm buffer tomorrow and then checking extractor.  

Wow, that's unfortunate - you had me thinking I should have bought a full-up CMMG PDW pistol but if it doesn't run right out of the box there's not much attraction.  Definitely drop an email to [email protected] - I corresponded with Nathen but there may well be several people behind that mailbox.  Nathen was awesome though, so see if he/they can help - IMO a full factory gun should run 100% OOB!!!!  I'm sure they can tell you how to get the buffer tube off, though if I were them I'd ask you to ship the whole shebang back so they could make it right in house... but I'm not them.

Good luck and keep us posted!
Richard