fitting Series 70 slide on pre-70s frame?

[jmstr]

I know that the series 70 used a different barrel and bushing from the pre-series 70 1911a1. However, will a series 70 slide [complete with barrel and bushing] work safely and reliably on a pre-70 1911a1? I want to get a new slide/barrel/bushing for general use and was wondering if the collet bushing on the series 70, combined with its barrel, would be a significant improvement over the traditional 1911 barrel/bushing system. Since I need to buy the slide/barrel and bushing, I could do either pre-70 or series 70: If the Series 70 will work on my frame and is safe/reliable on it. Please let me know if I am going in the wrong direction or am ok in my thought processes. Thanks!

 

[stans]

As far as I know, the only differences between pre-series 70 and series 70 guns was the collet bushing and a barrel that had a reduced diameter aft of the muzzle with series 70 guns, the markings on the slide and possibly heat treatments (depending on how old the pre-series 70 slide happens to be). The collet bushing can be replaced with a solid bushing. The collet bushing was supposed to provide a tight fit, but the collet fingers developed a reputation for breaking. I have no personal experience with the collet bushing, I have always used solid bushings. I recommend you use whichever slide you like the most and go with a well fitted solid bushing.