In the late 1960's, Numrich Arms (for one) used to sell "drop-in" .44 Mag barrels, that worked best on/in .38-40 & .44-40 Model 1892's & Model 92's, since the smaller original chamberings needed the mag throat bored out, and the cartridge guides changed, to accommodate the fatter .44 case.
They were "ok" for the occasional hunter, but certainly never stood up to a steady diet of shooting with ANY modern ammo - never mind at the levels a CAS event would require.
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