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In active service
M9 (Beretta 92FS, 9x19mm)
M11 (SIG P228, 9x19mm)
Heckler & Koch P9S (9x19mm) (Navy SEALs)
Heckler & Koch P11 ZUB (Underwater weapon) (Navy SEALs)
Mk 24 Mod 0 (SIG P226 Navy, 9x19mm) (Navy SEALs)
M9A1 (9x19mm) (USMC)
MEU(SOC) pistol (.45 ACP) (MEU(SOC))
SIG P229R DAK (.40 S&W) (USCG)
http://en.wikipedia.org/wiki/List_of_individual_weapons_of_the_U.S._armed_forces----
M11The M11 Sig Sauer P-228 was introduced in 1989. It is a compact version of the Sig P-226, just 7.1 inches long and only 1.5 inches wide. The Navy SEALs and Special Boat Teams consider it a favorite, and use it as their standard carry pistol as it is small, light, durable, accurate and easy to conceal. The M11 is a recoil-operated, semi-automatic pistol that fires a 9mm NATO round in both single- and double-action modes from a 13-round magazine.
In 2004, SIGARMS of Exeter, NH released a limited edition of specially serialized P-226 pistols produced to the exact same specifications as those which have been the official sidearm of the Navy SEALs since 1986. Designated SIG P226-9-NAVY, this unique version includes special phosphate corrosion-resistant finish on internal parts, contrast sights, a slide engraved with an anchor to designate them as Naval Special Warfare pistols, a unique serial # starting with NSW 0001, and certificate of authenticity.
The manufacturer raised over $100,000 for the Special Operations Warrior Foundation through the sale of these NSW serialized pistols. Established in 1980, the Foundation provides support, primarily scholarships, to ensure that all the children of Special Operations personnel who have given their lives in service to our country, will be able to go to college.
Specifications:
Manufacturer: Sigarms
Caliber: 9mm
Weight w/o magazine: 1.10 lbs.
Length: 7.1 in.
Barrel Length: 3.9 in.
Capacity: 13+1
http://www.navyseals.com/m11----
Sig P228 Country of Origin: Switzerland
Designation: Pistol
Calibre: 9mm Luger, .357 SIG, .40 SW
Dimensions:
Length: 180mm
Weight: 770g
Capacity: 12 rounds
When it comes to Close Quarters Battle the SAS use the Sig P228, it is lighter and slightly shorter than the Browning meaning that it can be manoeuvred more easily and aiming is that little bit quicker and steadier.
It's worth noting that you don't want a really powerful gun when in close quarters, the weight of the gun means you can't snap around as quickly, which means you take longer to aim and the weight of the gun makes your aim less steady, and there is also a much greater recoil which messes up your aim.
You also have to face the possibility that when you shoot a bad guy your bullet needs to stay in them and doesn't go through them and harm any hostages behind, or bounce of the wall, the SAS actually use special rounds when storming (planes particularly) that explode on impact, so that stray fire doesn't bounce off and hit a hostage (loaded in the Heckler and Koch's as well as handguns.)
The trooper will use the double tap method, firing twice very quickly before moving onto the next target. He will aim for the mouth, doing so cuts the spinal cord and blows out part of the brain (messy!) which prevents the brain sending the 'pull the trigger' signal to the gunman's finger.
http://www.sasspecialairservice.com/sas-guns-handguns.html----
Semi-automatic pistols are the most popular sidearms. Examples may include, but are not limited to: M1911 pistol series Sig Sauer series (especially the Sig P226 and Sig P229) Beretta 92 series , Glock pistols and H&K USP series.
http://en.wikipedia.org/wiki/SWAT#Weapons