You basically want to use your weak-side elbow as the pivot point for your entire body. Plant that elbow, square your shoulders to the target, and adjust your hips and legs appropriately to get NPA.
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Respectfully, I disagree:
Shooting prone with your shoulders square to the target like this is uncomfortable and difficult.
This is basically the same as attempting to shoot straight up while standing, it cramps the arms and your full weight is lying on your chest, which restricts breathing, among other issues.
When your body is oriented 30 to 45 degrees to the target you have a fixed anchor point with the elbow of the support arm. Bringing up the knee of the strong side leg opens up your torso and also rolls it to the support side getting your chest up off the ground assisting breathing and reducing the stress on your neck.
Neither picture completely expresses what I'm trying to communicate but I believe the OP will get the gist of what I'm saying.
When firing from prone and you need to adjust your NOPA you need to keep that support side elbow glued to the ground. If NOPA needs to go left, pick up the hips and pivot to the right
on the anchor point.
If your rounds are impacting high, pick up those hips and scoot forward
keeping that support side elbow glued to the ground, if shooting low, move hips backwards.
The two keys to remember are to keep that anchor point fixed and move your body around that point.
When ever you can't get to the range for some bang-bang time, find a spot where you can flop down in the house with a clear view of and electrical outlet and use the little round hole for a "target" and dry fire, dry fire, dry fire.
Just check the chamber first.