nopride2,
Thanks for setting me straight. I have long known that running hot water on the metal lid of a glass jar will loosen it if it is stuck tight and hard to unscrew. I was merely temporarily insane at the news of defective McGowen ".4241 caliber" barrels. I have dealt with this and am now back to reality.

sooooooo if the barrel is cold it is at the true bore but after it heats up when fired a few times there is less grip on the bullet minus bullet metal that smeared off

boom stick

If you go back on this thread you will see the calculations were done and the increase in bore diameter is extremely small. From memory the calculations were done at 100 *F and 400 *F

Mike