after 300rds, I decided to do a little more than wet/dry patches. I shoved a dry dewey phosphor bronze brush through the barrel and a nasty screech resulted. I had run a few wet then dry patches through already. I won't get a chance to shoot again until wednesday to find out for myself. Any chance of damaging a TRG barrel? Running dry was stupid. Cleaning wasn't even needed. Just bored, I guess.