found the problem

[Tom Thomson]

Three days ago I started a thread "pattern spread" abt shots stringing to the left. Turns out that having someone else shoot it or changing bullet weight would not have changed a thing. The scope was moving in the rings. Scuff marks showed it moving abt 1/8" till it stopped on a shoulder and the group went back to normal.
tommyt

[scooterf79]

That will definitely cause it. I didnt ever used to think about that stuff. Since I've been on here, I try to check nearly every time I shoot to make sure everything is tight as it should be.
Scooter

[stomp442]

Upgrade to some Burris Signature Zee Rings and slipping will be a thing of the past and they will neer leave a scope mark.

[BlueDog]

Tom, you may want to go back to your original post and link this thread, that way if someone is searching in the future for the same issue they can utilize this thread as another thing to check. Might be helpful for the next guy.

[gotcha]

Congratulations on your trouble shooting skills and all that helped you get there.