You know, I could grab one of my Colts and measure the cylinder wall thickness, but I am not going to. This is such a bad idea, that I am not going to encourage it by writing down any technical information beyond buying a particular book.
Not 100% sure what you are trying to say, but if you are trying to compare Ruger, Colt, and, Browning with a guy who wants to try building a complicated firearm as his first effort, you are all wet. John Browning apprenticed for years with his father, who was also a gunsmith, before he started designing firearms on his own. And with all due respect, Browning was a genius, with dozens of patents to his name. He had forgotten more than most of us will ever know about designing guns. Bill Ruger was a talented mechanical engineer who knew how to use new concepts, such as Investment Castings, to produce firearms more economically than his competitors. Sam Colt was not a gun maker, he was an entrepreneur. He relied on others to iron out the details of how to put his ideas into production. Colt's most enduring contribution to firearms manufacturing was using ideas created by the industrial revolution to mass produce firearms.