I have a post ban sar-1 and I want to put a compensator on it.  I bought a k-var press-on compensator, but without the right machinery the barrel will most likely be bent.  I am considering threading the barrel and the compensator, and then installing it permenantly.

Are there any legality issues doing this?

Pres

Legally, you can do it as long as it's blind-pinned, with the pin welded over, or high-temp silver soldered (1100F), or four or more equidistant spot welds.

You can also legally thread to a 'non-standard' thread, for which no flash hider exists, and then the brake/compensator need not be made permanent.

Mechanically, you might have trouble threading a brake/comp which has been bored for a press-fit and getting it to thread on securely.

This is true.  Hopefully, there is enough metal.  Otherwise he can machine the inside diameter a little bit, and then silver solder it on there.  I honestly don't care to remove it, I just want a compensator.

Pres