About 20 years ago I started putting bipods on rifles and Contender pistols.
I have always used sandbags or a rest until recently.
This past summer I was working on loads for a new rifle and experimenting with different loads looking for good groups. Rather than drag all my shooting stuff to the range to fire 1 or 2 groups I made up a small bag with the necessities and stuck a Harris bipod on the rifle. I was impressed with the results. Enough to make me think the consistency offered by the bipod was affecting the groups. This was especially true when I compared notes taken while shooting the same rifle off of a rest with a bag on top.
I tried the tripod on a second rifle and again I was impressed with the results. They were as good or better than the rest or just sandbags.
My initial "guess" is that the consistent location of the bipod and the consistent pressure on the bipod provide more consistent results.
