I went with a .45 Colt ( I don't handload for that one) - and use CorBon +P commercial loads for deer hunting.
IIRC, some other non-cowboy loads are available from other companies also - like Buffalo Bore, etc.
I can't attest to it as fact, but have heard that some non-original Winchester Model 92's are problematic in .44-40, accuracy-wise due to differing bore specs.
Those reports, however, are related to the European/Italian M92 clones - so I don't know that a Miroku/Winchester would also have issues in that chambering.
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