There's not a whole lot of Miroku/Winchester M1895's in .270, since they were such poor sellers than Winchester returned most (if not all) of their NOS to Miroku in 2001/2002 for conversion to the then "newly in demand" .405 - so, "leaving it alone" does have some merit.
If it's in excellent condition, it may be saleable for enough $$$ to buy a .405, etc.
There were a few conversion articles in RIFLE Magazine back about then, mostly to .375 Hawk/Scovil or the .405 - which would be my preference, having owned a 2002 .405 - but a .35 Whelan is a mighty attractive commercially-available chambering, too.
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