Are barrel mounted bi-pods detrimental to accurate shooting? I would think that they would affect a barrel's harmonics and prevent good grouping.
I had one on my AR-15 and could not hold a group for anything. It could have been something else but maybe the bi-pod contributed to this.

i prefer stock- affixed bipods but since they are often unweildy and sometimes permenent people like to get the barrel fixed ones, which are also cheaper. I think possibly they hurt accuracy because it is too far out on the gun.

I too prefer stock mounted bi-pods just becasue it mess's with the barrels harmoncis like you said.

i use homemade shooting sticks. only thing i don't like about them is having to carry them by hand, i've forgotten them in the truck on a few occasions.