Glad you found something that worked. If you do want to find other powder/bullet/seating depth combinations to work in that rifle, you can do the OCW/Ladder tests. They can, and may have saved you some time and headache with your rifle.

If I have issues with any rifles after I have done a OCW/Ladder test and found a good load, I first confirm at the range with a fellow Army buddy to confirm its not just the shooter (me). I then proceed to check that every single nut/bolt/screw/swivelstud is properly toqued to prevent any abnormal harmonic vibration issues that may arise or change during the shot string. Add what davemuzz mentioned and you should have a resolved issue provided there is nothing mechanically wrong with your firearm and you arent resting the barrel on anything haha, I see a lot... I mean a lot of people make this mistake during my trips to the range.