The Glock 19 is popular for a reason. But in actual combat, the 9mm ammo has left something to be desired, which is why the .40 S&W was invented for U.S. officials.
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New Gen5 GLOCK models: update of the GLOCK 22, 23 and 27 – The fifth generation and the role of the .40 S&W caliber.40 S&W
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The Glock Model 23
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The Ultimate Glock Guide
3 Glocks Used by Agencies in the U.S. Department of Justice