For me, recoil is pretty bad shooting from a bench (there's probably a way to do it right that I don't know about...). I can maintain glass on target shooting prone, but not from a bench. Shooting prone, I slightly load the bi-pod and I'm square behind the rifle. Set the rifle lined up w/ the target, get behind the rifle (body in line w/ rifle) with eyes closed, muscles relaxed, open eyes and if you're not on target, reposition. My guess is the scope will be lined up with your forehead... If you’re in correct position, recoil will be manageable.
Work on dry firing from position. Focus on 'strait back' trigger pull w/o adding any movement / torque in your grip and follow through. Dry fire several times then shoot a cartridge. If you have a friend that can help, dry fire several times then have the friend load the rifle without you knowing if there is a loaded rd in there or not. If you’re flinching, that will bust you.
Factory settings on the rem triggers can be improved a lot; you may want to discuss this with your smith. It will reduce the impacts of your flinching.
The rings are likely too high. Get an experienced shooter to take a look at you behind the rifle.
Who replaced the stock? IME, 700’s are very sensitive to torque, especially if the stock is not glassed to the action.
If you want a reduced load, skip the trailboss and load ~168gr match bullets w/ 4895.
Good luck.