I will be testing loads for three rifles when the weather clears up. I intend to use a Caldwell Rock and rear bag. I understand that there are better rests out there, but I will use the Caldwell. I have developed loads using sandbags and bipods (both on a bench and on the ground). I want to improve consistency between shots as much as possible. Two of the loads are intended for longer range target, one is a varmint load for 300yds max. Is there a reference out there that will provide guidance on how to use a front rest and rear bag? Rest position on the fore stock, cheek position, hand position, etc. I think I want the rifle to slide straight back consistently. I would appreciate advice on this, or direction to another thread. Thanks.