Nifty Old Revolver!
Ronin--
Congratulations on your excellent purchase.
I urge you NOT to do any manner of conversion on that fine old 2nd Mod Hand Ejector.--The best you would accomplish would be a decent imitation of a military 1917 S&W, and it would ruin collector's value.
I'm sure there are may who would be willing to swap you another revolver which would shoot .45 ACP/.45 Auto Rim for your old pistola. (Whoops! Wrong border.)
You have exactly the right idea about obtaining proper ammo/brass and shooting your .455 in original caliber. And, also--Please do not try to load it up as a magnum or hot .45 Colt--It is a fine, old, original piece, and I believe you would gain much more from the experience of shooting it with loads similar to what the RCMP and Brit military used, than ammo similar to what everyone else at the range uses.
According to Barnes' Cartridges of the World, the .455 Revolver MK-2 factory load is a 265 RNL, at 600 fps. The bullet typically has a rather long nose, nearly conical but with a well- rounded point.
If you can locate the proper bullets, excellent. Some custom casters will size .45 Colt bullets to your desired diameter; most won't.
If you can't locate exactly what you want, Find someone who sells the Winchester 255 LRN Flat Point, hollow base .45 Colt bullets. There are easier to locate now than they were a few years back, due to the popularity of Cowboy Action Shooting. These soft lead bullets are swaged with a hollow base, to about .452 diameter, but the soft lead and HB design allow them to slug out and you can get good accuracy with ‘em.
This bullet with 5.0 gr. Unique will just about duplicate factory ballistics.
Good shooting, sir!
Best,
Johnny
PS--If, after you mess with your revolver a bit, you are dissatisfied with the trouble of making your own ammo, I have an excellent shooter S&W HE in .45 ACP/.45 Auto Rim. Perhaps we could work out a swap.
JPG