OK, I know a little bit about the series 70 model 1911's because I got a couple of them with the spring finger barrel bushing. What I'd like to know is what's diffrent about a series 80 & series 90 etc. etc.. I see on the internet auction sites about a 1991 model. What the heck is the diffrence between all these models? Has Colt made any changes since the 1991 ( what ever that is ) model? Are newer guns any better than old ones? I've become a real 1911 fan since I retired & would like to find out as much as possible about them. Never had this much time before to persue questions.