I shoot an original Robert Chaplain percussion 13 gauge SxS, made in Birmingham, England, mfg. in the 1850's. On the rib, it says "London Fine Twist", and has all the British proof marks appropriate for that era. A gunsmith told me it was unsafe, and the barrels would "blow up" if I shot it. He was not familiar with blackpowder, and just repeated an often repeated falsehood. I proofed my gun with progressively heavier loads, pulling the trigger remotely with a string. I got as high as 1 and 7/8 oz. of shot and 120 grains of Goex FFg, and the gun was fine. I routinely shoot it with a standard load of 1and 1/8 of shot, and 80 grains of powder (volume), now mostly Pyrodex RS, as even before the Goex crisis, it was hard to get real black in my area. (I know, internet, shipping, hazmat and all that, just not interested, pyrodex has been fine over the years. Save my limited supply of real black for flintlocks) I'd give it a whirl, something super-cool about shooting originals!