The .50 ones no good so sticking to .45 cal barrels, I made two .45 muzzle loading ones in 12/15 steel and they came out good. So will try 4140 with my new system to see if it works and if any good will maybe fit it to my Sharps. And yes, I`m using A4 printing paper as well, seams to work, lots of confetti when it goes bang.
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