Scott Gunner / Quora
Scott Gunner
Long term shootist, former lawman, and CAS competitor. Author has 483 answers and 802.5K answer views2y
I shot a pair of Pietta 1858 Remington replica pistols in cowboy action matches for quite a while, using Taylor's R&D conversions. Pretty sure each fired at least 500 rounds of cowboy action loads and were still perfectly fine. They regularly shot under 2″ groups at 25 yards from the bench, and under 4″ groups in one handed duelist style.
I learned a LOT, above and beyond my gunsmith and military armorer's courses.
As others said, if it's an original, best not to shoot it at all. If its steel frame model from Uberti or Pietta, and has the conversion cylinders made by Taylor's, then stick with loads under 850 fps. Factory cowboy action ammo from HSM (200 grain lead) ran right under that limit in my guns and was accurate. Any “Cowboy Action” loads from Fiochi, Magtech, etc. should be fine.
I've also seen them using 45 Schofield and did all right, using low pressure/velocity lead ammo. There's also a “45 Cowboy Special “ which is a 45 Colt case cut down to 45ACP length with similar loading to the 45ACP specs, but that is pretty much limited to experienced hand loaders.
My hand loads were mid-range pressure/velocity 200 grain lead and were VERY accurate in that pair. They did NOT like any bullet heavier than 200 grains, and DO NOT USE JACKETED AMMUNITION! If you handload stay away from the higher pressure producing powders like Titegroup. However, Trail Boss and Clays were very good. I imagine the other makers of conversion cylinders and kits also have similar limits and will include the safety instructions as well.
If it's a brass frame, dont even think about conversion cylinders! You WILL destroy the gun, and probably be severely injured or worse.
The Uberti ’58 Remington is slightly better quality but stick to my advice. I've seen guys blow up a conversion BP revolver a few times and the results were both spectacular and horrifying. They lost fingers and/or an eye on 3 occassions, and bystanders were wounded with the shrapnel. If you are going to mess with one of these things, acquire the safety and user manuals for EVERYTHING and follow their instructions religiously!