I did not have much luck with Google-Fu, and most results deal with Gen 3 and Gen 4.
I have a G20 that is a Gen 1 (one of the first 1000 in the US according to Glock), and I just received an Alpha Wolf 6.6" threaded barrel that is marked 'Gen 3/4', (compatibility was not listed on the website). My slide is off being milled for an RDS, so I can not function test until it returns. My 'Mark 1 Eyeball' thinks they are the same, BUT does anyone have experience with Glock (any model) Gen 1 to Gen 3 barrel swaps? Thanks,