View Full Version : Stripped reciever extension on M4 stock. Any ideas?

12-13-2007, 4:45 PM
I have an old stag arms M4 style stock which i got in a trade that has a stripped reciever extension. Unfortunately the castle nut is stuck behind the stripped area of the tube and I can't get it out. Any ideas? I've kinda accepted that I'll probably have to throw away the stock as it would only be like $40 to replace it. But is there any way to salvage the castle nut? Should i break out a dremel and cut through the reciever extension to free the nut? I have pics of this but unfortunately this website won't let me post pics of that size. any ideas? What could I use to cut the stock tube?

12-13-2007, 5:28 PM
You could use a hacksaw and cut the extension just in front of the jam nut and then just spin the nut off (nut=steel vs. aluminum extension) without damaging the threads. If you're really worried about the threads, carefully notch the inside wall of extension with your dremel just until your through the aluminum in a couple of spots for relief before twisting the nut off.

Good Luck!

Lon Moer
12-13-2007, 5:51 PM
- the actual stock can be removed from the back of the receiver extension by pulling down on the stock lever and sliding it off
- then I would fix the stock wrench in a vise, hook the castle nut onto the wrench and force it to spin off. This may even restore the threads on the receiver extension.

12-13-2007, 6:11 PM
I'd imagine the castle nut to be hardened. If that's the case, force it off the threads. You never know, you might be able to salvage it for a future project; such as a chop and paint job on a rimfire rifle. There was a guy who used an old AR stock and epoxied it to a Ruger 10/22 stock. It looks pretty damn good too, better than most AR style stock/adapters for the Ruger 10/22. It has uses if you think of them.

Back to topic, remove the actual stock, put wedge the extension in something so that as you try to turn it the under area prevents it from rotating, and force it off. Any part of the thread that has rolled over should be pushed back up. Same concept as chasing a thread with a die, only this will be more difficult and take a little more force because it won't actually cut but will push and fold the burr back up.

12-14-2007, 4:22 PM
I'd imagine the castle nut to be hardened.

It's soft so you can stake it.

12-14-2007, 7:56 PM
It's soft so you can stake it.

It's always the most obvious facts that you forget...