from Wikipedia:
Although it is an inexpensive cartridge to reload,[1] care must be taken by the reloader because of the extremely thin walls of the cartridge case. Energy and pressure levels for handloading are determined based on the strength of the firearm action to be used. Because most firearms chambered for this cartridge are older (e.g. early model Winchester model 73 and 92 rifles as well as older Colt and Smith & Wesson revolvers) factory ammunition usually has reduced pressures from what can be achieved through handloading. Most factory ammunition exhibits ballistics of about 1,200 ft/s (370 m/s) and 325 ft·lbf (441 J) of energy at the muzzle with a 100-grain (6.5 g) bullet from an eighteen- to twenty-inch rifle barrel. The performance characteristics of the cartridge listed in the sidebar should be considered maximum performance parameters obtainable, and even then only with a modern weapon designed for higher pressure loads. Factory-type loads - and reloads mimicking factory type loads - are the safe maximum loads for use in older weapons chambered for this cartridge, as most of the weapons the cartridge is chambered for are. Few if any concerns still manufacture hunting weapons in this caliber.

This matches my understanding that High power loads are no longer sold by manufacturers and factory loads are safe for pistols that were made for smokeless powder. Black powder age guns did not have heat treated cylinders and should not be used with factory ammo.

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Revolver luvin' Mountaineer