G'day all.
I knew I would get some controversy going here, but that is good, because a forum should be an exchange of ideas.
I should state at this point that the idea was to get better than 45-70 performance at a lower pressure by using a larger capacity case. When this is suggested the problem is always brought up of people possibly overloading with dire consequences. If we follow this logic through we would not be using vintage firearms at all. Damascus barrels, Nitro for Black and early hammer NE rifles and guns could not be used because somebody might use the wrong load. I think all of us here admire and respect GW for the great work he has put into his book and I for one trust his pressure figures.

If such a conversion did prove viable I would be using the the 25,500 psi load suggested in GW's book, with probably a lighter projectile such as the Woodliegh 350 RNSN, which should drop the pressure even further. Having said that if I did such a conversion, it would be sensible I believe to go back to the old idea and stamp the load on the barrel or action. The most practical conversion
would probably be the 45-110, which can give a 200fps advantage over the 45-70 for about the same pressure.

All the best and good shooting, Ian.