Wow! This thread sure brought back memories. I used to own a Webley that had been converted to .45 autorim. Selling it was one of the dumbest things I ever did!
For reloading I cast my own bullets using a Lee mini bullet mold which was originally intended for muzzle loading rifles. This is a hollow based bullet that measures .454 and weighs 298 grains. The mold model is 454-298-M. Make sure you use pure lead. The original loading used a 265 grain hollow based bullet, so this heavier slug will hit a little higher.
I got the reloading recipes from an old British gun magazine which I think was titled, "Target Gun". It listed several powders, but the best accuracy for me used black powder (make sure you clean well after shooting). I can not remember how much black powder was used, but it was a compressed load.
I just dug up some old notes and in smokeless powder I used 3.5 grains of Red Dot.
Believe it or not, I actually used that old Webley at a Metallic Silhouette match and managed to hit a 200 meter ram, which didn't even wiggle. However, the old girl did take down the 50 meter chickens with authority! And it was pure poison on pepper poppers!
