All I know about it, is that it was his "Devil Stopper" and never failed to floor a charging elephant. I seem to recall that the 2 bore bore size was around 1 1/2" & that the gun weighed some 25 or 30 lbs. At that, they'd line up 20 'kaffers'(their name for their packers) each one holding the one in front and the lead one would hold the gun to fire it. This was so it's barrels could be cleaned & loaded fresh. They did this once a week. On each shot, there'd be all 20 of them spread around on the ground. Seems to me, they were using small bodied bushmen for packers at that time. HE wrote he fired this gun some 20 times himself, and that it produced in him an awful flinch he could never get rid of and lamented every having it made up. Most of us today, wouldn't fire an 8 bore with the loads they used on Elephant, more than once.
: He had a slug mould made for his other stopper, a 4 bore double, which ruined it's killing powder. Obviously, a 1/4 pound ball, just over 1" in diameter, is all that's really needed in the sorst situation. The 4-bore slug, however wouldn't kill worth a damn.