One other thing that most (yes, most; about 80% from what I've observed) folks do that causes inaccurate shooting is how they use their trigger finger. Keeping ones aiming eye open when the arm fires is also important 'cause if you don't do this, you'll never be able to call your shot.
First off, the jerk, quick-pull or yank ones finger drives the trigger back hard against its stop. That's going to put enough force on the firearm to move it's alignment with the intended target away to someplace else. It's all a subconcious mental process that starts when the sights are well aligned and aimed at the desired point of bullet impact and the instant things look perfect, "NOW" is the mental command to the trigger finger to make it shoot the arm immediately.
Secondly, it doesn't matter whether the trigger was pulled as a result of that subconcious NOW thought that jerked the trigger back, or, a perfect gentle squeeze that makes the arm fire somewhat unexpectedly. As soon as the shooter's subconcious senses feels the trigger break, they flick their trigger finger off of it. I think this is based on ones safety issues and they subconciously don't want their finger on the trigger any more than what's needed. Problem is, that "FINGER FLICKING" is so fast, it puts enough counter force on the arm that it moves off the desired place to put the bullet where it's intended to go. "Follow through" is the term that referrs to the shooter keeping their trigger finger all the way back until they stop moving from recoil. Doing this ensures there'll be no disturbing the arm's position while the firing pin (or hammer) falls, fires the cartridge and the bullet goes through the barrel. After the bullet's left the barrel, one can move whatever body parts they want to 'cause it'll not effect that "perfect shot" in any way.
Had a guy on a military rifle team who was nororious about jerking and finger flicking. But he didn't believe me saying he had this problem. He could not shoot his Garand very accurately in spite of its capability to hold 2/3 MOA at 600 yards with a good lot of M118 match ammo. Best he could do was keep most of his shots inside the 36 inch eight ring on the 600 yard target. So I decided to prove to him that while he could hold and aim his M1 very, very well, he just didn't have good trigger control.
Had him lay down slung up in prone on the 600 yard line, he would single load the Garand, then get into position but his trigger finger was not on the trigger. I layed down beside him then put my right hand thumb behind the trigger guard and my trigger finger on the trigger. After he breathed deep a few times and held his breath, the rifle was then held very still on target. I'd just gently squeeze the trigger firing the shot about 10 seconds after he held his breath. Two shots got a good zero on target. Then he (we?) shot 10 shots for the training session. All ten shots were in the 12 inch ten ring; 4 in the 6 inch X ring. He could not believe he shot that well. And he finally realized he was a finger-jerker and finger-flicker. After some ball and dummy practice, he finally became the best marksman on the 4-man team I was training.
Last edited by Bart B.; November 7, 2012 at 10:53 AM.