[kronckew]

If you get anywhere near a decent charge in that, I'd tie it to a heavy bench & use a long cord to pull the trigger from a safe distance, and preferably behind something solid, like a concrete wall. Whatever max charge you use, i'd not shoot it thereafter with more than half the load you 'proofed' with. Even then.... Get some Bubba and shout 'Here, hold my beer! as you apply for your Darwin Award. If you have a misfire, wait a good while before going anywhere near the front end. 2 days outta be enough.

p.s. - I read something I didn't know recently, Colt's Walker .45 six-shooter was renowned for blowing up with a full 70 grain charge. The steel was essentially crap. One reason they are so rare & expensive now. They backtracked and recommended not more than 50 grains of FFFG and oversized balls to better seal the chambers to prevent the ajacent chambers from firing all together. A rather spectacular occurance. FFFFG was priming powder for flintlocks and a bit too fast for the main charge. FFG was for cannon. FG for BIG Cannon. Colt stopped making them & made the Dragoon instead, with a shorter cylinder that held less powder, and used better steel. (and had a redesigned loading lever that actually stayed in place when firing) I'm glad my Walker was a modern steel version proofed for the full 70 grains (I used 50). It kicked a mite. - I sewed up a thin leather belt for the loading lever thing. Thought I was smart and wondered why no-one thought of that. Turns out that's what many dragoons did with their Walkers.

Pee ess 2. Civil war sojers, when it got hard to ram home their mini balls, would urinate in the barrels to dissolve the residue, rather than waste water. Works best with a hot barrel. Smells better with a cold one. No one probably noticed as battlefields were very smelly places anyway.