I'll admit it is a little late to be asking this, but when I did my last build, I noticed the barrel fit into the upper with tighter tolerances than the ones previously.

The barrel had been previously fit to a Colt A2 without incident, and was removed without problems.

The keyhole forge marked A4(supposed to have been RRA, btw!) would only let me insert the barrel most of the way, but became too snug to push in any further by hand about when the index pin was ready to enter the slot.  Close to zero tolerance, and it did not seem like the slot was too narrow.

So my buddy Wiley C. whispered in my ear, and I used a barrel nut and usgi wrench by hand to snug the nut and barrel into the receiver, and it did not take much force to bottom it out correctly.

BUT HOW WOULD ONE REMOVE THE BARREL in the future?

And did I do a bad thing by using the nut to bottom the barrel in the receiver?

Paladin

You did remember to lube the barrel and the barrel nut?

Quoted: You did remember to lube the barrel and the barrel nut?

If I understand the mechanics of how the barrel is inserted into the receiver, you could chill the whole gun and then heat up the receiver with a heat gun.  It will heat much quicker than the barrel and make this process easier.

That should work.


Prolly wouldn't even need a heat gun - the aluminum receiver is going to warm up a lot quicker.