Help with AR15 barrel change?

**Missdrift** · March 30th, 2012, 10:26 PM

Hello!

I need some help switching the barrel of one of my AR uppers to a new receiver. I'm switching from a fixed CH to a flat top. I'm having trouble getting the barrel nut off, and wasn't sure if anyone could give me some advice etc.

Thanks!

**cdi** · March 30th, 2012, 10:27 PM

Try twisting the nut off with an ar15 barrel wrench.

**Missdrift** · March 30th, 2012, 10:34 PM

Originally Posted by cdi

Try twisting the nut off with an ar15 barrel wrench.

I guess I should have mentioned that in my original post. I have one of the DPMS ones, but no matter what I do, it won't budge.

Would heating it up work? I have a heat gun I could use, but I'm not sure.

**cdi** · March 31st, 2012, 12:28 AM

Generally speaking, the upper is clamped firmly in the receiver block and the wrench employed to twist off the nut.

What kind of AR do you have there?

**Legion_Prime** · March 31st, 2012, 02:01 AM

Put it in the freezer overnight, then clamp it in a secure action block (or whatever they call the ones for the uppers) apply heat to the barrel nut with a torch (your GF's hair dryer ain't gonna cut it). Then go at it with the barrel wrench. If that doesn't work, try turning the wrench the other direction.

**cdi** · March 31st, 2012, 11:27 AM

If you give me a call at the shop, (215-996-1603) I might be able to help you out over the phone. I do not want to spend a lot of time typing questions...

I had a Daniel Defense gun in here last week that was so tightly breeched I had to use a 2' pipe over the barrel wrench. On the other hand, A S&W mp15 that was here a few days ago was barely hand tight. And that's not the first S&W AR I have seen that is not properly tight.

**elementfreak431** · March 31st, 2012, 11:53 AM

Definetly stick it in the freezer for 3 or 4 hours. The aluminum receiver and steel barrel will contract at different rates which will make it easier to take off. I had to do this wil my step dads M&P 15 when I was free floating it. Just stick the upper in the freezer for 3 or 4 hours, pull it out/put it in the vice block, then twist the barrel nut off. Ive ever tried applying heat like Legion said, the freezer was enough for me.

**Missdrift** · March 31st, 2012, 12:42 PM

Thanks for all the suggestions everyone. I've put it in the freezer and I'll let it sit in there for a few hours. Then I'll just put a pipe on the wrench for more leverage. I'll let you all know how it turns out lol!

**MEK1911** · March 31st, 2012, 03:26 PM

Not to state the obvious but you did remove the gas tube? I find that it goes better to take off /unclip the "C" ring so the tension from the weld spring is off the wrench.