I started out with a G23. Been carrying that for a couple years. Ordered a 550 to start reloading for it. Wasn't too long ago I got to molest my first 10mm glock in a store. I told myself that if the 23 left i would get a 10mm. A couple weeks ago I got offered a little more then what I needed to let the 23 go. Came home today with a G20sf. Now I am looking for info on reloading 10mm. I have heard that Federal makes the only SPP brass for 10mm. Everyone else makes LPP brass. One question I have is, is it just large pistol or is it magnum primers? I see a lot of people talk about 800-x for 10mm. Is that the best powder for 10mm? I plan on carrying this gun, but this is going to be for practice ammo only. at least for a good length of time. I'll buy my carry ammo for now. I will also gladly accept any other info you would like to share. Thank you in advance.