Now, a number of media outlets are reporting that the U.S. Marine Corps has announced that Glock 19s will replace the venerable Colt M45A1 .45 ACP pistol for its special operations troops—particularly the Marine Expeditionary Unit Special Operations Capable (MEUSOC), which, unlike the rest of the U.S. military, never gave up on the M1911 pistols when the military switched to the Beretta M9 in 1985.
The Marine Special Operations Command (MARSOC), renamed Marine Raiders in 2014, were issued Colt .45s, but will be adopting the Glock 19 as well.
One of the reasons the Corps is abandoning the M45A1 and the .45 ACP, according to this post from American Rifleman, is that there are times when Marine operators require a pistol suited for concealed carry that's also capable of carrying more rounds. Also, last year, the Raiders were issued the Glock 19 alongside the 1911, and logistically, it didn't make sense to have two handgun calibers in the same unit, the story says.
The Glock 19 was part of the fourth-generation of Glock pistols introduced in 2010, along with the Glock 23, which are the reduced-size “compact” versions of the Glock 17 and Glock 22 pistols.
The Glock 19 is chambered in 9 x 19mm, features an integrated rail, polymer frame with a stainless steel slide, a 4.01-inch barrel, and a capacity of 15 rounds, with optional 17- and 33-round magazines.
The big difference is the Glock 19 weighs just 23.65 ounces unloaded and 30.18 ounces loaded. Moreover, it's significantly smaller than the full-size 1911, with a width of just 1.19 inches and a height of 4.99 inches, meeting the Raiders’ requirement for a more concealable sidearm. Glock pistols have an excellent reputation for exceeding requirements in endurance trials and are prized for their simplicity and reliability.