A few things to check when using a Joypod:
1). Be sure that the rear bag is settled before starting to shoot.
Tap your stock into the bag and move your rifle back and forth, check your reticle, If it tracks straight, vertically perfect, and comes back to the original point of aim, it's fine. If not, re-adjust.
2). If you use Podpad, also be sure it is settled before starting to shoot.
Tap the top where the feet rides on using your palm, create a flat top.
Be sure the Podpad does not move, remove gravels etc under - they can act as roller bearings.
3) Be sure your shooting mat is not springy/spongy. This is very important.
Use proper mat, or cut it if possible - so your rear bag will sit directly on the ground.
You can use a sand filled doughnut (not a rigid spacer) to stabilize the bag on uneven ground/mound. It's also very cheap.
4). Be sure your whole body position is right - so your shoulder is square.
"Follow" the recoil with your shoulder, not "against" it. (sorry, don't know to say this properly in English?)
Don't move too much, don't make unimportant movements during shooting string.
Always be as consistent as you can in all things, how you hold the rifle, even how you breath before taking the shot.
5). Be sure rifle and rear bag are aligned.
6). It does not matter (from my own experience) whether you light-hold or let the joystick in the air when you shoot. I believe the bullet already exited the muzzle before the joystick moves in your fingers.
I lightly hold the joystick myself, just like how I hold a billiard stick.
All of us need to adapt with the equipments we use, rifle bipod rear bag trigger etc and understand how they work and react during firing.
If everything is alright / set & done correctly, your rifle will track beautifully straight and your reticle will come back or very close to the original point of aim, every-time.
Everything is right, you can also see your own score in the scope after recoil / every shot you made. This means that your rifle/setup does not move/shift to the left or to the right if you are a lefty...assuming most modern barrels today are right hand twist. You also don't have to change the bipod's setting, the height, the cant etc, at all.
You only need to adjust the condition with the joystick, the joystick will do it all.
That's why we call our bipod: JOY-pod.
There should be something wrong/not right if you still have to change the setting of the Joypod or the rear bag or your body position after you shoot a round or some.
Must be from one of those above.
Note: I am not an expert in any way, it's just from my own experience and from what I learned/seen in the match.
Hope this help,
seb.
To add:
And believe it or not, use heavy rear bag. The heavier/the more stable the better.
To add:
Check out this video, me shooting my .308 with 200 gr bullets @ QRA Queens last 2014: