A specialized item for 45-70 rifles. New in its plastic protective case a custom reamer from Pacific Tool & Gauge - 45-80 match finishing reamer. This is intended to ream 45-70 barrels' chambers to 45-80 - that is, to render your barrel for 2.68-2.70 inch overall cartridge length. This is to allow using longer 45-90 brass trimmed .010-inch. . . . . $120.00 shipped.
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If you are a gunsmith/gun maker who is comfortable working on flintlocks, I would be interested in trading for your service.

quote:

Originally posted by dpcd:
Ok, I must be missing something; 45-90 brass is 2.4 inches long. If one wants a 45-80, just use the 45-90 reamer and brass; remember that it will only hold about 75 grains of powder anyway under a 500 grain bullet. The original 45-90 was an Express round with a 300 grainer allowing the use of 90 grains of powder. (Black).

You are correct. Marlin 1895s (with the exception of a few egregiously expensive conversions) maxes out right about at . . . 2.68-2.70 inches of cartridge overall length. Before I shot my hunting partner's very heavy 45-70 425-grain handloads, I intended to lengthen the cartridge my 1895s would shoot. Half-a-dozen 45/425/1950s later, I decided not to allow my rifles to become more powerful than they were. But I'm 5'9" and 138 pounds, so bigger men may not be intimidated by more power.

Hope I responded to your question.