Do not use locktite unless you don't plan to remove the barrel, it works too well for the new DW wrench. Check Numreich or some of the auction sites for the older style wrench, the T style, it allows more tightening pressure. You might also try checking tightness after a few shots(this was recommended in the old Monson manual). Make sure the threaded areas are free of oil when assembling, as this will also allow loosening during firing. My newer barrels will loosen after 30 or 40 rounds if I don't check after 15 to 20. When tightened hot, it will be a bear to remove cold. I've used a candle to heat the barrel enough to remove when overtightened when hot. Heat just enough to loosen. I have 2 of the older wrenches; one very used and cracked and one in the original wrapper, both bought on Ebay. I also have the new doorknob and plan to grind off two ends to make it into a T grip. I saw one done nicely at a gun show, unfortunately it was with a 44 for sale.