The pistol is one of the best bodyweight exercises for leg training. More than likely the average person is working on getting a FULL depth two leg back squat which is a great starting point. Learning the pistol takes time, flexibility and hard work. So what is a pistol? The pistol is a single leg full depth squat. It is started from a standing position and you extend one leg out in front of you as you sit back and down hovering the opposite leg above the ground for the entire duration of the exercise. With the working leg, you descend into a full squat and come back up. If you’ve never tried this before, then you’ll discover that to master the pistol takes flexibility, strength, and balance.
Here are some flexibility exercises to learn how to do the pistol squat.
Pistol Drill #1: One-Legged Box Step Up
The best way to build the required flexibility for regular squats is by using a box. By working with boxes of different heights, you can train the movement pattern and gradually, progressively, get down to the full 90 degree position.
Pistol Drill #2: One-Legged Box Pistol Swing
Still use the step-up on the box but adding the rotational component of the Pistol. Move to the side of the box and steps up and down with a hanging leg to a small swing to find balance and full range of motion in the hips for the squatting leg.
http://https://youtu.be/BZHdEWVLiag
Using these tips you will learn how to add strength and depth to do an effective pistol !
references
http://breakingmuscle.com/bodyweight/2-flexibility-drills-the-keys-to-progressing-your-pistol