Armalite muzzle brake removal
I have an Armalite rifle with a gill type brake on it that I cannot get off. It had a pin though the bottom that I was able to get out.
I cannot get it to turn or move at all.
It's possible it was brazed on.
Often, when you find a rifle with a pin in the muzzle attachment, it was brazed on.
This may have been done during the Assault Weapon Ban as a means of meeting the law about muzzle attachments, or it may have been done to make a short barrel the legal 16" length.
If you think this was a factory barrel set up, contact them for advice.
If it's not factory, all you can do is assume a braze job.
To remove you have options:
One is to cut the brake off without damaging the barrel or any threads on the barrel.
The second is to heat the brake and muzzle to a red heat until any braze melts than unscrew the brake while it's still red hot.
"Red hot" means a DULL RED not cherry red heat, of at least 1100 degrees, which is what this type of silver "solder" (braze) begins to melt at.
Before doing anything, try to find out how exactly the brake was attached.
Is it the 2-slot or 3-slot break? IIRC, the older 3 slot breaks are all threaded on, but some of the newer 2 slot breaks are pressed on. You can use a larger bit than you did to drill the pin out, and drill down SLOWLY, to see if it is threaded or not (you will expose the threading on the break just before you reach the threading on the barrel and not damage the barrel if you go slow enough). If it's pressed on, you will have to press it off, or cut a slit the legnth of the break to relieve the tention, then tap it off. On mine, which was threaded, I had to drill the pin ALL THE WAY out, which meant PAST (deaper than)the threads before I could unscrew it.
Assuming that you don't mind trashing the brake. If I didn't have acess to a lathe I'd use a disc grinder. Clamp the barrel up and very carefully grind down flat with the bore until you get to the barrel. Slow and careful. If it's threaded you'll hit the top of the threads in the brake before you get to the barrel. If you do it on both sides you should be able to remove the brake pretty easily. If at that point you find it's brazed it will still be easier to get it off than with the brake intact, it will heat easier too, less mass.