In the early 20th century the U.S. Army found its trust .38 revolver
incapable of stopping some attackers in the conflict against Moros in
the Philippines. An Ordinance Board headed by Colonel John T. Thompson
(of "Tommy Gun" notoriety) and Colonel Louis A. La Garde decided that
the army needed a .45 caliber cartridge to provide adequate stopping
power.
John Moses Browning, who was working for Colt, had already designed
an autoloader pistol that become known as a .38 Super. When Browning
heard of the Army's interest in a bigger gun, he re-engineered the .38
autoloader to accommodate a .45 cartridge. of his own design and
submitted it to the Army. Firearms were submitted by Colt, Luger, Smith
& Wesson, Savage, Bergmann, Knoble and White-Merrill, but in 1907
Browning's Colt model was selected along with the Savage design. But,
upon testing both selected pistols, neither met the Army's desired
perfection, so they appointed a selection committe in 1911. Browning
remained determined to see his pistol perfected, so he went to the
Hartford Colt factory and oversaw production.
When Browning submitted the pistol again, it was put through a
"torture" test on March 3, 1911. Each gun would fire 6000 rounds in the
test. After each 100 rounds, the pistol would be allowed to cool for 5
minutes. After each 1000 rounds the pistols would be cleaned and oiled.
After all 6000 rounds, the gun would be tested with deformed cartridges
before being rusted in acid and submerged in sand and mud.
Browning's handgun passed all of the tests with flying colors, and
on March 29, 1911, the Colt-produced .45 automatic pistol was selected
as the official sidearm of the Armed Forces of the United States of
America and named "Model 1911."