I have a Colt Series 80 that is about 3 years old. I was thinking about purchasing a WWII slide(Ithaca, Colt, Remington-Rand...it really doesn't matter) to put on my pistol. Will those slides interchange with my gun? Thanks for your help.
Take the series 80 components out of your frame and replace them with a TJ's Custom "Series 80 Frame Slot Filler". It runs about $5 from Brownells. That SHOULD be the only issue. A GI slide should function fine (will probably be a bit loose on your frame). Your barrel/barrel bushing should drop into a GI slide without any fitting. You didn't say what Series 80 you have, the Gold Cup and Enhanced Model's barrel hood will be narrower than a GI barrel. That'll be an eye-sore, if you have an Enhanced or GC barrel. The back of your slide may not mate up flush with the top-back of your frame, another eye-sore, but won't cause any funtion issues. I assume your doing this to reduce wear and tear on your Colt slide for trips to the range? All of the above advise is subject to this: While it SHOULDN'T require any fitting, ALWAYS be prepared to do some minor (and sometimes not so minor) fitting when dealing with 1911's. There are very few "Drop-In" parts when dealing with the 1911. Good luck!