Originally Posted by
10x25mm
The SAAMI cartridge drawing for .45-70 Springfield calls for a 35 - 55 degree outside cha**** (angle measured from a parallel to the bore axis) extending 0.045 - 0.055 inch forward from the very rear of the case. This is more than half of the entire 0.060 - 0.070 inch total rim thickness of the .45-70 case. Insufficient rim cha**** would tend to increase friction at the location where your cartridge is stopping, and it could also stop the case at the receiver bolster behind the breech block.