The material in a bag has a lot to do with it. If slick, like teflon (BR shooter use teflon tape on theirs, and talcum powder, etc, so the rifle will slide easily).the rifle can slide and not hang up, even for that nanosecond, which effects accuracy. The leather or plain cloth bags can make the rifle hand up. I used a Doktor back bag, with a slick plastic like material on the wings. The front bag is leather with a plastic seat. I'm now using a Eagle brand rest, that I just got. Used to use a, shoot forget the brand, one I bought in 1965, but it was outdated. But the bags make the difference. As you noted, can go from okay to real good, just by changing out the bags. BUT both the front and rear bags should be slick where the rifle rests.
