Quote Originally Posted by lysander View Post
3) Biasing springs - They completely reverse the intended purpose of the weights in the buffer. The whole point of the loose weights in the buffer, is that during the forward acceleration of the bolt during counter-recoil, the weights will, observing Newton’s Laws, slide to the back of the buffer body tube. Then when the bolt impacts the barrel extension, and begins to rebound off it, the buffer weights impact the front of the buffer body and the rebound is cancelled out. The physics of this can be demonstrated by Newton’s Cradle.

Biasing the weights forward means the weights will impact at the same time as everything else, and the carrier will rebound. Fortunately, is only an issue in full automatic fire, and even then is highly depended on ammunition and how the gun is held during firing, so most people won’t notice the problem.
I think we've talked about this before but the bias spring in the VLTOR buffer is very soft. I don't think the weights stay at the front (muzzle-end) of the buffer under acceleration from the action spring.