"chasdicapua"I find that the accuracy when shoot off a bag is related to how far forward or back on stock you rest the gun on the bag. I'm pretty sure it has to do with the harmonics of the vibration from the shot. You can experience this by taking a butter knife or other longish, thin metal object. Hold it between your thumb and index finger with one hand and flick it with the finger of the other hand or tap it on a hard object. The metal object will vibrate or not, depending on where you are holding it with your thumb and index finger. Move your holding spot up and down the object until, when you flick it, it vibrates. This point is where the vibrations moving up and down the object in a sort of infinity loop cross. It teds to be about 1/4 to 1/3 the distance of the object from either end point. I'm pretty sure this hold true for the rifle and why accuracy is affected by how far forward or back on the rifle you rest it on the bag. My experiments have shown that resting the rifle farther back towards the action produces better results. But, that may just be for my rifles. I suggest you experiment with this as my experience has shown there can be quite a difference in accuracy from just a few inches forward or back.