Buy the patent, not the gun, Pipes? To follow your thinking, it's an important variation of an evolving mechanical design, and a desirable one, and one of personal importance to you. The OP wants it as a project gun. You encourage the thought that it's a good choice as he won't be getting another for that price where your views are known and accepted. Apparently Crosnoe doesn't share your views, or really anybody at all's views, as he's sacrificing "70% case color" and 70% of some other mysterious stuff for 3 bills and hasn't noticed the innards. Funny old world and people have more fun than anybody. But anybody knows that what makes a good "project" is something so cheap that there's no great loss of outlay if correction and restoration goes south or proves too tough. I think the OP has got the best of it in a gun which is as lowdown cheap as Murphy believes it should be and yet very valuable to you.
jack
