Did you check to see if the rifle has enough sear engagement? I backed off on the sear engagement on my 700 LSS, and found that when I cycled the bolt fast and slammed it forward, the sear would trip. I set my sear by turning the engagement screw clockwise (inward) until the pin fired. I backed out from this point counterclockwise a little more than 1/2 a turn. There still seems to be more takeup than I would like at this setting.