Carpe

OK, first things first.

I would take the scope off the rifle and shoot and get / find a load that regulates 100%. I would try to use a bullet weight around 286gns.

Only change ONE component at a time.

At some point, try a couple of other bullet weights (lower / higher) to see if you can get it to regulate with these. Whether you do this before or after the step in the next paragraph is up to you.

Once you have the gun regulated without the scope, put the scope on and try the exact same load.

More to come.