Well, I must first say that I am not an "experienced" reloader. As a matter of fact I have two calibers under my belt as of july of 2012, which ared .270 and .40....So with that said, I had the same apprehension, read all about the .40 caliber and the glock being dangerous and what not. But to be honest, I've ran about 300 or so reloaded rounds through my glock 23 without a single issue...knock on wood
Hopefully I get some reassurance from the experienced guys here, but the way I look at it, if I keep two things constant, charge and cartridge overall length, then I should be safe................this is where the seasoned guys chime in.......
I know there are quite a few steps in the reloading process, but the thing that "scares" me is a catastrophic ignition. So the way I look at it is if I am very meticulous with my measurements, then I should be safe.....
My recipe is 180gr RNFP, 5.8 grains of Unique, and COAL of 1.125......this has worked for me flawlessly in my glock.
Don't forget to crimp.