Farmer Joe you have to think about the power a gun puts out when you try and figure out what size LDC would be needed, the gun in question was putting out about 900fpe. This was one of the first really powerful big bores I made an LDC for, most of the others were hovering around 300fpe so it was a bit of a guessing game. I thought 12 inches would work well but that just took the bark out of it, so the extra was to make it more comfortable for the person shooting it. You are not going to get a big bore anywhere near the levels of the 22 and 25 caliber guns, unless you put a garbage can size LDC on it, lol Congratulations to the winner, I hope I can think up some more of these for future competitions, all the best, Neil.