He had been a Army officer and the 7 1/2 inch Colt was service issue. He was an expert so he would be comfortable with and maybe insist on a piece that was for experts only. And of course, as he said, it was handcrafted (weren't they all in his day?). And it was a 45 (I think), not a 44/40 or a 38/40 or anything else. So all things considered I'm saying it would be a 1911, of Colt manufacture, but totally reworked by an artist among gunsmiths, every part handcrafted. A 45 but possibly a longslide 10mm. The 10 could fill in for a carbine, in an expert's hands.