Had an interesting discussion the other day,

with an ex-soldier from the sandbox. After seeing his YUUUGE arsenal, we talked about our fave handguns. He basically told me I was full of crap cuz I liked a Glock 22 (40 cal).
WELLLL, I've known several 'badge carriers' who 'bet their lives' on their sidearms when things get serious They like Glock 22's.
SO, I Googled, 'most popular hand gun law enforcement'.
Surprise? Not really.
For many reasons, the Glock 40 cal is most popular.
Glocks NEVER jam and they can pump out 14 lethal rounds (better than a Colt 45) before you can blink.
If you like something else, fine, but....
You can disparage me, my car and family, but don't dis my piece....

The Glock 22, which is carried by 60-70% of American police officers, holds 15 rounds in a standard magazine.
Glock has proven to be exceptionally rugged.  It holds up to extensive firing without jamming, requires a minimum of maintenance, and shrugs off abuse. Due to all of the above reasons, as well as attractive pricing, most police departments have adopted the Glock as their standard issue weapon, as well as officers who buy their own weapons.