Really, this is my favorite bipod, however it is not rail mounted, and not readily available. It started as an M60E3 light machine gun bipod. And like many other military bipod it is coaxial mounted and very solid. The bipod gives the best possible stability and control when mounted coaxial with the bore, and as close to the muzzle as possible.
When the bipod is coaxial to the bore, the rifle does not flop side to side, it rolls smoothly with much less X/Y directional movement. Also, when mounted as close to the muzzle as possible, the angular movement is greatly reduced. When you move the rifle butt, the muzzle moves less, and the angle to the target is effected less. All of this contributes to control and accuracy.
I learned that my 1918A2 BAR was a very controllable full auto weapon when shooting prone from the bipod. This is a prime example of the principle of this design.
However, It is not a good idea to mount a bipod on the end of your precision rifle barrel, as it really messes up the harmonics.
So, I decided to modify my new at the time DTA SRS's forearm and a bipod to do what I wanted; function as described above, and fit and look as if it were designed for it. This what I came up with, and it has proven to work very well.
I realize this design not for everyone, but perhaps the information will be useful to someone. Enjoy your shooting!