Fix for using bipod on hard surface
As some folks have noted here, the problem with using bipods on hard surfaces is the bounce that throws shots off. Upon recoil, the legs of the bipod get dragged backward, and bounce. The solution is to "load" the bipod so it is forward in the bipod slack, and then the rifle can recoil back without moving the legs. Expensive bipods provide the ability to load the bipod. Inexpensive ones are too stiff and therefore the legs drag backwards and bounce on the surface that fraction of an inch during the first part of recoil.
You can see this in the CVLIFE 6-9" bipod that costs less than $20 on Amazon, and the more expensive Harris bipods. The problem is that there is a hard stop on the legs that prevents backward movement and a tough spring holding against that.
My solution is to lighten up that spring so you can load the bipod against that stop and then let the rifle recoil against the spring without dragging the feet. Look at the attached picture. In the fully loaded position, the legs are angled forward relative to the line of the barrel. I simply lightened up that spring so it just barely but surely keeps the legs down, but there is enough slack to let it recoil without dragging the legs. As you can see, I used a small plastic tie to lengthen the spring about 3/4 inch - just enough to take slack out of the un-stretched spring. The first picture shows the bipod loaded against the stop. The second picture shows the rifle recoiled about an inch back. It's just enough. The spring holds the legs well in the folded condition too.