4070 SS

[ken s]

Hi Guys. ok. I'm probably the only one reading this..but...here is the scoop on bore size of the Original 40 70 sharps. and bullet sizes.

This is taken verbatim off the net:
This is another cartridge with ballistics similar to a half-dozen others of different make or origin. There are actually more than a dozen 40-caliber cartridges with powder charges of around 40 to 70 grains and none offer any stupendous advantage over the others. Like other 40 Sharps numbers, this one used a 0.403-inch-diameter bullet, weighing 330 or 370 grains. These chambers were cut to use bore-diameter bullets (often paper-patched). Groove diameter is typically 0.408 inch to 0.411 inch. A number of Lyman bullet molds are available in this size. Although longer, this case has the same basic body as the 30-40 Krag. However, because head spacing is on the rim, it may not be possible to safely use that case to make the 40-70 except for very-low-pressure loads. (Cartridges of the World 9th Edition)

SO.. I use a .403 paper patched 330 bullet, and a RN 330 grooved at .410 sized.
They are both correct for the size of the original bore. 64 2f, and jamison brass
made for the original from B Arms.
The PP is for bore size and the RN grooved fits the Groove diameter.
All chamber and eject....no problem....
Ken