I've got the exact same setup, and 150gr sierra pro hunters in front of 43gr of imr 4895 with Win. brass and primers, shoots as good as I could want. 165 gr Nosler BT's and 41gr of powder shoot as well or better. I would first check your rail and rings for play. I haven't swapped out the washers but It sure doesn't seem like a bad Idea, especially if everything else failed. Oh yeah, I did that trigger spring bending also and it worked well. A better trigger pull can't hurt (if yours is factory). Keep us posted on your progress and good luck.