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Figure 3 - Prone Alignment
Positioning for Prone Shooting:
When you drop down into prone shooting position, you will be lying on your stomach, with the axis of your body angled a little to the right of the line to the target, as shown in Figure 3. (This assumes you are right-handed.) Your shoulders should be square with your spine; your spine should be straight. Your legs should be comfortably spread in a "V", with toes pointed out. Some people bend the right knee a little - that is a personal preferance.
Your right arm should be as shown in Figure 4 - notice that the upper arm, torso, and the ground forms a triangle, providing lateral stability.
The rifle butt should be pressed firmly into your right shoulder as shown in Figure 5. Again note the triangle formed by the upper arm, lower arm, and the rifle stock.
Your left arm should be positioned with the palm of the hand positioned somewhere along the hand rail, as shown in Figure 6.
Figure 4 - Right Arm Position Figure 5 - Rifle Butt Placement Figure 6a - Left hand placement - High Figure 6b - Left hand placement - Flat