Thanks for the help. I didn't consider the magazine fitment. That could've saved me time thinking about it.

I have a Glock 40 Gen 4 on order. It'll be a holstered sidearm for hiking, fishing and camping. Concealed carry isn't an issue for this. I planning on getting a KKM 7" threaded barrel. Now I'm wondering if I can do a 10mm magnum conversion to get the most out of the longer barrel. I know Double Tap carries ammo.

Is it possible to convert a Glock 40 to 10mm magnum? If so, where do I start? Do I have KKM chamber the new barrel to magnum dimensions? How do I know what recoil spring to upgrade to? Will empty magnum cases eject stock 40 ejection port?

Any help is much appreciated.