The same article(s) by Mr. Pearce about the .45 Colt we are referencing, he broke down the .45 Colt into four or five pressure ceilings. Depending on the age, size, and metallurgy in the firearms referenced.
Also, check out the Gunblast article about the New Vaquero, from when it was introduced. Cylinder measurements of the major players are compared, and the new midframe Ruger cylinder is a bit bigger in diameter than the Colt's. More of a safety window for the .45 ACP loads.
I just think of these midframe Ruger's as available, more economical versions of the Colt New Frontier. You can afford two for the price of every Colt. I know, four clicks, the name (that's been sold to corporations, and run into the ground however many times since Sam passed away), and the romance...