Well here we go. It was the last day of deer season here in North Idaho. I had been holding out for a big buck and finally got my opportunity on the last day which was Saturday. Me and a buddy hiked into a sweet spot which we were surrounded by clearcuts. We hiked in in the dark and were glassing for about 2 hours when I finally spotted a deer 500 yards way down hill. I told my buddy where it was and he could not spot the deer w/ his cabelas binocs. I handed my swarovski el's and he was like holy s*** that's a big buck. I said yeah the biggest I have seen to date in real life. So I got ready to setup for the shot. I have a remmy sendero sfII w/ a leupold MK4 lit mil dot 6.5-20x50 on it w/ ferrely rings and a harris brm bipod. It's shoot's in the .2's consistently w/ berger 180's, nosler brass and fed gm215's w/ 68.3 grains of retumbo. Oh yeah the caliber is 7rm. I can't be happier w/ the performance, until this day. So I had chamber a round and put the safety on and be were waiting for the deer to turn broadside. He does and I get into position and gently ease the safety off and BOOM! the gun goes off. What the frick!! I look down at the deer it's still there and my buddy is like shoot! before it runs. By now I'm shook up pretty good at the fact that my high dollar setup just went off by itself. I chamber another around and try to hold steady and fire and miss. By now I know my nerves are in now shape to continue firing and really bums me out considering I shoot 3 times a week and shoot 1200 yards at least 1 day a week. So what would cause this? Anybody know? Why would this thing go off why taking the safety off? Lite trigger? Trigger is a stock pro mark x set to 2.5#.