I wouldn't suggest welding precision barrels... I get the "welded or pinned" muzzle devices part for length on carbines... But anything in the barrel would effect the steel. Uneven temps on steel will undoubtedly affect your barrel in a negative way. If you're guttsy, using JB weld will be a sure fire way of perminantly affixing the barrel nut if you use it like locktite on the threads.