The classic firearm was carried, mostly by military officers, through the Vietnam War.
Pictured is a close-up of the Colt 45 ACP model 1918, a civilian model, manufactured by Colt. For the first time in several decades, a military-spec Colt 45-caliber pistol will be sold to the U.S. military as the sidearm for a select group of U.S. Marines.
The newest Colt .45-caliber pistol is touted for its durability and design. It is tested to make sure it can be dropped in water, covered in mud, immersed in sand or ice or left in a dust storm -- and still be able to get off a round when you fire it.
"Virtually, it's indestructible," said Casimir Pawlowski, who works in international sales and technical services for Colt Defense. "You can drive over these things with a Humvee and they're still gonna work. It's like a brick that shoots bullets."
An order last month of new M45 Close Quarter Battle Pistols for the Marines is the first purchase of any Colt handgun in almost three decades by any branch of the U.S. military, though .45-caliber Colts were a trusty sidearm of the Army and Marines for most of the 20th century.
Pawlowski started working at Colt Defense several years ago after a 30-year career as a Navy corpsman. In 1977, he joined the medical corps serving the Navy and U.S. Marines who carried an earlier version of the Colt as their official sidearm -- the Model 1911 .45-caliber automatic.
"We saw the .45s out there, and that's what the guys wanted," Pawlowski said.
Connecticut's historic gun manufacturer first sold its semiautomatic Model 1911, designed by John Moses Browning, to the U.S. military in 1911. At the turn of the 19th century, the military was looking for a stronger handgun than the .38-caliber revolvers used in close combat during the Philippine-American War. The .45-caliber promised more knock-down power -- more likely to kill than injure -- compared with the .38-caliber.
Browning's design was an impressive development from 19th century single-action Army revolvers, which held six individually loaded bullets. It has been called the "most respected handgun" and was carried, mostly by U.S. military officers, during both World Wars and in Korea and Vietnam.
But in a controversial move, the federal government switched in 1985 to Italian-owned Beretta to provide 9-millimeter pistols as the new official sidearm for the military.
The Marines' contract to buy up to 12,000 pistols for $22.5 million over five years means it accounts for about 2 percent of Colt Defense's annual sales. That's not enough to drive the success of the company. But the historic return to Colt sidearms is significant, and it's a morale boost within the company.
"I call it in the category of 'cool,'" said Gerry Dinkel, CEO and president of Colt Defense.
"It just has a lot of ring to it when you have something that's this long-lived," Dinkel said of the Model 1911.
The return to West Hartford-made Colts from Italian-owned Beretta also carries some patriotic pride.
Dinkel said, "A lot of people have said it's great to go back to an American supplier."