The U.S. Army produces many training guide / manuals.
This link is for the M9 9mm Handgun (2005)
This link is for the M4/16 Rifle (2008)
Bullseye Pistol – Online Encyclopedia Handgun marksmanship
FIREARMS TUTORIAL General Firearm tutorial/definitions with forensic photos (Photos are Graphic )
Physical / Mental Conditioning for Accurate Shooting in Competition
Accuracy is a combination of the following: Ammunition, Firearm, human. For the Human: Eyesight, Physical Conditioning, Psychology, Training. Firearm Overload has all of the information. The links presented will help in the understanding of these critical areas.
Grip Strength – Grip Strength Training for Shooting Firearms
Understanding and Intervention to Enhance Shooting Performance