pea shooter, that guy at S&W was full of it. If mine could loosen up 1/8 turn in 100 rounds after torqueing it tighter than I found it I'm sure it's happened before. I'm going to make a second "tool" from PVC pipe as I don't like scratching the barrel with the steel tool and 3/4 black iron pipe. I have stripped almost all of the lube from those areas of the barrel and nut and have retorqued it again. I'll be heading to the range later this week (weather permitting) to put several hundred rounds through it and see if it stays put. If this doesn't work, some sort of barrel vise will be needed. Mike in Texas