Alright, I'm getting winter fever, and looking around for some sort of firearm project to keep me amused while my knee heals up. I have been toying with trying to get one of my 10mm's to run 9x25 Dillon for some time, but nobody seems to make 1911 barrels any more in that caliber. Bar Sto has sworn off doing it, and the only place where you can easily find 9x25 barrels is Lone Wolf for the (gulp!) Glock. So I went to Bill's yesterday, and asked to see a G20 or G21, and they gave me a G21, and the first feeling I noticed when holding it was a feeling of, well, claustrophobia. I have huge hands, which fit nicely around Hogue finger groove grips on a DE50, and can also hold an entire reloading n00b over a fire and roast them for dinner. (I'm fireproof, n00bs are not....) So my fingers felt bunched together on the grip, and the trigger guard was too close to the palm of my hand, so when I reached for the trigger my finger would touch the outside of the trigger guard, and I had to bend the finger first and then put it in the too small trigger guard.
Then I tried pulling the trigger.

WTF?? Is this the long road to Tipperary?? You squeeze and squeeze and squeeze and it FINALLY goes click. So serious question for Glock shooters: How do you figure out where the set point is so you can shoot accurately?? I couldn't feel a damn thing until it went click.
At any rate, the 9x25 Dillon Glock project is in the wastebasket and never coming back out, but I am mystified on how you can pull back just far enough to draw a steady bead on the target and then trip it in that instant when everything is lining up.
EDIT 2 days later after going back to Bill's:Well, from the advice I got, I went back and tried the trigger after it had been held down and the slide dropped home. It was a lot better, but still squisher than a stainless Ruger Redhawk trigger pull, where you swear somebody had stuffed some week old sushi into the sear mechanism...
As far a size, yes my hand is flat out too big for a Gen 3 G21. The bottom edge of the slide digs uncomfortably into my 2nd finger, and the top middle of my index finger and the bottom tip of my index finger on the other side both press against the trigger guard fairly firmly, so dragging my finger along is about 30% of the total force of the pull.