dougk- you might try this. Heating the gun and assembly expands the metal. An old machinest trick, if it's possibly had Locktite applied, is to put it in the freezer. Metal contracts in the cold, and you might possibly break the seal between the threads. In your post, you say you have a stuck barrel. If you mean the barrel nut on the end, and you have one of the metal barrel nut wrench's try this. Take the gun, and hold it like you were shooting it. Put the barrel nut wrench on the end, and lean/push with the end of the gun against a wood board.(garage wall stud,tree outside,etc) And turn the gun, not the wrench. If it's a barrel stuck in the frame, take 2 pieces of soft wood, clamp the barrel in a vise between the wood, and again, turn the gun, not the barrel. I like the Kroil, so don't be afraid to let it soak overnight. Good Luck-gypsyman!!
We keep trying peace, it usually doesn't work! Remember 12/7/41 9/11/01