U.S. Marine Corps special operations (MARSOC) operators now have official permission to use the Glock 19 pistol in place of the standard M9. There are many reasons for MARSOC buying all these new pistols. The Glock 19 is lighter (at .595 kg/1.31 pounds empty) and smaller (174mm/6.85 inches) than the M9, which is a 914 g (2.1 pound empty), 217mm (8.5 inch) long weapon that has a 125mm (4.9 inch) barrel. Both are 9mm weapons with a magazine that holds 15 rounds.

In the 1980s the M9 replaced the World War I era M1911 .45 (11.4mm) caliber ACP. This is a 1.1 kg (2.44 pounds empty), 210mm (8.25 inch) long weapon with a 127mm (5 inch) barrel and a 7 round magazine. Both 9mm and 11.4mm pistols are only accurate at up to about 50 meters. The M1911 had more hitting power, while the 9mm weapons are a bit more accurate. Loaded, each pistol weighs about 230 g (half a pound) more. The Glock 19 is considered more rugged and easier to “handle” although some marines still yearn to have the 11.4mm pistol again.

It’s not just MARSOC as all the services have been trying to replace the Beretta M9 9mm pistol. The air force tried to replace the M9 back in 2007 and was ordered by the Department of Defense to back off. But now the services have a more compelling argument. The army, in particular, is finding the many of its oldest M9s are, literally, breaking. Some components (especially the barrels, frames and locking blocks) tend to break on older, especially heavily used, weapons. Since September 11, 2001 the army has used its M9s a lot. There are also a host of other problems, like the shape (too awkward for some users), trigger pull (too heavy) and lack of a Picatinny rail for easily mounting accessories. The safety switch is in an awkward position and troops in combat often accidentally put the safety on when cocking the pistol. That can be fatal (for the user) in combat. More modern designs have something more efficient (and less of a dirt catcher) than the open-slide and spent cartridge ejection system of the M9. Another sign of the times is that the M9 is not equipped to screw on a silencer, an accessory that is more commonly used these days. Despite all these problems the Department of Defense refuses to replace the M9 although SOCOM has been able to do what it always does and obtain whatever weapons it believes it need.

Most of the problems with the M9 result from the fact that it is a design that is over three decades old. Pistol technology has improved a lot since the late 1970s and that can be seen in the pistols that are popular with police forces. Cops can often buy their own pistols and tend to get the most modern, but proven in action, models. Thus many troops in the combat zone leave the M9 they were issued back at the base and go into the field with a 9mm pistol they bought themselves. This has often been a Glock 19, which has long been a police favorite and popular with troops in other countries. Many armies do not replace pistols as frequently as police forces, or special operations troops. But in Afghanistan and Iraq regular combat troops used pistols a lot, and the M9 was showing its age. As you can see, it’s not just the wear and tear, it’s also obsolescence in the face of advances in pistol design.

Meanwhile in 2012 the army had to order another 100,000 M9 9mm pistols, each costing $640. This was just to replace the M9s that were falling apart. The U.S. military (mostly the army) already has over 600,000 M9s and that purchase keeps the M9 in service at least until the end of the decade. The U.S. military adopted the 9mm pistol in 1985 largely to standardize ammunition with NATO and to replace the M911 .45 caliber (11.4mm) pistol with something smaller and lighter. All other NATO states used 9mm for pistols. At the time it was noted that most 9mm pistols were carried by officers and support personnel, who rarely used them, in combat or otherwise. Many American combat veterans disagreed with the switch to a 9mm pistol, but that advice was ignored.

But times have changed. Since 2001 American troops in Iraq and Afghanistan discovered, through combat experience, what types of weapons worked best at close range to take down the enemy. It was the same with SWAT teams and commandos all over the world. When conducting a raid and finding yourself up close and personal with someone trying to kill you, there is a need for a heavy caliber pistol or a shotgun (firing 00 shot or slugs). The premier pistol for ensuring you take down someone is still the .45 caliber (11.4mm) or .40 caliber (10mm, but only with a heavy bullet) pistols. There is also a .50 caliber (12.7mm) pistol, but only very large people can handle this one. The 11.4 and 10mm pistols are light and handy, compared to assault rifles or shotguns, and have a long history of quickly taking down an armed and determined foe.

SOCOM (Special Operations Command) came into being a few years after the M9 was adopted and immediately began planning to bring back .45 pistols for its commandos. Actually, many Special Forces and SEAL operators never gave up using the .45, as it was the ideal pistol for many commando operations. SOCOM had its own budget and was allowed to adopt a number of 11.4mm pistols for its personnel. The U.S. Marine Corps ordered 12,000 11.4mm caliber pistols (for $1,900 each), mainly for use by its SOCOM and recon troops. The MARSOC (Marine Special Operations Command) troops have, like the army, navy, and air force components of SOCOM, quietly replaced most of their 9mm pistols with 11.4mms. For several years the marines supplied their special operations troops with older M1911 model .45s, refurbished (or built from scrounged up parts) in a marine-run facility.

In the 1990s, SOCOM adopted the Heckler and Koch Mk 23 SOCOM model. This is a 1.47 kg (3.2 pound) 11.4mm pistol with a 12-round magazine and the ability to use a silencer. It is expensive, at $2,400 each. Loaded with a silencer and laser aiming device the Mk23 weighs 2.29 kg (5 pounds). The Mk23 is a precision weapon, capable of accurate fire at 50 meters (51mm/two inch shot groups). The Mk 23 is for offensive operations while the lighter and cheaper USP Tactical model was later introduced for personal protection and other duties not requiring the heavier Mk 23.

As the U.S. Army Special Forces discovered, if you are well trained and know what you are doing you should carry a pistol, in addition to your rifle. Not the official issue M9 9mm pistol but something with a bit more stopping power. The Special Forces prefer new model 11.4mm pistols, although 10mm weapons are also popular. The reason for this is that you are most likely to be using the pistol indoors, where your target is going to be really close. You want to knock him down quickly, before he can get at you with a knife or even his hands. Many troops are getting their own larger caliber pistols and most commanders have been lenient on this issue.

The army and air force do not have the same needs as SOCOM and simply want a 9mm pistol with fewer flaws and more of the latest pistol tech than the existing M9. MARSOC ordered the Glock 19 for marines who did not need a heavier pistol but wanted something better than the M9.