With .32-20 black powder or cowboy loads a conversion cylinder would not likely overstress the frame or arbor from a pressure standpoint, the diameter of the cartridge is problematical and the cylinder is likely not going allow full length cartridges to be chambered in a conversion cylinder. You might need to flush load. Not to mention needing a custom conversion cylinder. Since it's not a production conversion cylinder, and since if it were a viable choice the cowboy action folks would likely be on it already, I suspect that it's not completely practical.
Suggest asking in the black powder and cowboy action forum here, where these conversions are discussed daily by some pretty expert and friendly folks. I took the liberty of sending a note to the moderators suggesting moving the thread there. Hope I don't overstep my bounds by doing this. Want you to get the best information available.
Willie
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