Most data for the .45 3 1/4" Sharps (Sharps NEVER chambered a rifle for ANY 3 1/4" case)

As a heads-up on actual fact, the REAL .45-120 was the 2 7/8" Sharps case which was loaded with up to 120gr. of black powder and up to a 550gr. bullet, thus, it was called, among other things, the .45-120-550. AGAIN, Sharps NEVER chambered any rifle for a 3 1/4" case in any calibre. Winchester, on the other hand, did, using the British cases for the .45 and .50 3 1/4" BPE's. Thus some gun smiths on the Frontier of the US, particularly in St. Louis, re-chambered some Sharps rifles for the 3 1/4" Winchester cases. The Winchester loads, as noted in COTW used light weight bullets attempting to duplicate the Express rounds of the DR's.

ducmarc, you are comparing 2, 3 1/4" cases, one showing data maxing out at about 26,000PSI and the other maxing out at about 44,000PSI.

The .45 3 1/4" nitro case has a slight capacity advantage as it is a slightly larger case at the base with more taper than the quite straight case normally called the .45 3 1/4" Sharps. The difference in capacity is not great.

A Ruger #1, chambered for the .45 3 1/4" "Sharps" will easily duplicate & exceed any load that could be presented for a .45 3 1/4 Nitro Express for the Double rifle - The .45-120 Sharps merely needs to be loaded appropriately, as if it was a wildcat ctg., which, basically is, in that rifle.

The Ruger will handle higher pressures than ANY DR.