I cant pull back the slide all the way. The thing is completely built… trigger pin, charging handle, etc. However, I cant pull the slide all the way back… The slide fits onto both front/rear rails. I just cant pull the slide beyond that. I can take the slide down using the takedown button. So… what am I missing here ?
Ive built numerous glock frames… so not a newbie…
Thoughts ?


You are correct. Remove the firing pin spring cups, remove the spring, remove the stock plastic spacer. Put the printed sleeve over the firing pin and push it all the way to the rear. Put the spring over the firing pin (no cups) and insert the assembly into the slide channel (make sure you already have the stock channel liner installed in your slide). Lastly, put the M3 through the printed donut and put that into the channel head first behind the firing pin. Install backplate (don’t forget the extractor spring assembly) and you’re good to go.
youre sure the cups arent needed ? the illustration seems to imply the spring is captured behind the cups. although the cups arent clearly shown in the illustration.
I’m sure. With that spacer sleeve you couldn’t install the cups if you tried. The spring would be fully compressed before the end reaches the spot on the firing pin that retains the cups.
Normally the cups are there so when you pull back on the firing pin, the cups (which are locked to the firing pin) cause the spring to compress. As a result the firing pin is held almost all the way forward (it free-floats with no spring pressure the last few mm of forward travel).
The Franken9 works “backwards”. You want the spring applying rearward, not forward, force on the firing pin. So the channel liner, not the cups, becomes the forward spring stop and spring compression holds the firing pin all the way to the rear. It’s a really clever design in how it reuses the firing pin and spring in a completely different way.
ok… reconfigured the fiing pin assembly per your response. fraken9 fix build is completed… now just need to get to the range this afternoon.
thanks!
I wouldn’t go as far to say you’re a life saver. But you certainly saved me a lot of frustration! Thanks.
I wouldn’t go as far to say you’re a life saver. But you certainly saved me a lot of frustration! Thanks.