For real penetration with a .45-70, try our method of vetting bullets for an Elephant hunt.
Target = 5/8 inch steel plate
Rifle = 1886 .45-70
Bullet= 450 grain Punch
Velocity of load= 1800-1900 fps
Range = 50 yards
Process = Fire
Result 1 = .458 daylight hole in plate
Result 2 = frontal brain shot went through head into body = DRT
CRS, NRA Benefactor Life Member, Whittington Center, TSRA, DWWC, DRSS
Android Reloading Ballistics App at
http://www.xplat.net/