02-05-2014, 10:02 PM
It is hard for me to determine how tight your upper to barrel fit is with out being there myself. Most upper to barrel fits are too loose rather than too tight in my experience. I have always been able to wiggle even blue loctite barrels out of the uppers after applying heat. I would be very careful not to tap the barrel in if it is too tight causing a failure of your upper receiver barrel channel. I would measure the inside diameter of your upper barrel receiver and compare it to the outside diameter of your barrel extension to see what were working with.