Editing Colt Single Action Army (section)

==Mechanics==
[[File:3colt.jpg|thumb|right|First Generation Single Action Army from 1918, .32 WCF (.32-20)]]
The Single Action Army action is a refinement of the earlier Colt percussion revolvers and the Colt 1871 cartridge revolver. The cylinder is mounted on a central axis and operated by a hand with a double finger with which more extended action allows the cylinder-ratchet to be cut in a larger circle, giving more torsional force to the cylinder. Four notches on the face of the hammer engage the sear portion of the trigger, affording four basic hammer positions. The hammer rests within the frame when it is fully lowered. Drawn slightly to the rear, the hammer engages the safety notch of the sear and holds the firing pin out of direct contact with a chambered cartridge. Like the earlier percussion revolvers, the Single Action Army was designed to allow loading of all the chambers.

The safety notch replaced pins on the rear of the percussion revolver cylinders, which served the same purpose as the safety position; that is, preventing hammer contact with the primer/percussion cap. According to the original instructions from Colt, as well as the U.S. Army Ordnance Department, the revolver was to be carried with all six chambers loaded and carried with the hammer half-cocked in the safety notch. However, beginning sometime after the [[Second World War]] and after the introduction of the Second Generation single action in the 1950s, some gun-writers began strongly advocating the practice of leaving one empty chamber under the hammer.<ref name="Keith" /> It is likely this was recommended after the Second World War because with the changed tolerances of the re-designed Second Generation Single Action Army, a sharp blow could damage the re-designed half-cock mechanism and allow a fully loaded revolver to fire.<ref>{{cite book |last1=John A. Kopec |title=A STUDY OF THE COLT SINGLE ACTION ARMY REVOLVER |date=1976}}</ref> Drawn back about halfway, the hammer engages the second notch. This cams the cylinder bolt out of engagement and allows the cylinder to rotate for loading. Fully cocked, the revolver is ready to fire. Cartridge ejection is via the spring-loaded rod housed in a tube on the right side of the barrel.

It is possible to fire the SAA rapidly by holding down the trigger and "fanning" the hammer with the other hand. [[Ed McGivern]] dispelled the myth of the inaccuracy of this procedure by shooting tight groups while fanning the revolver.<ref>McGivern (2007) pp. 101–103</ref>