Love my 5700 elite with AB. Wouldn’t go hunting or to the range without it. Highly recommend if you are new to them to signup for their free webinars on basic and advanced kestrel courses. Buy once, cry once and don’t look back.
Midway has a great sale going on Bushnell DMR series scopes right now - https://www.midwayusa.com/product/1020586712
Not sure if these are within budget, but I have had great experience with them - repeatability/return to zero/tracking, etc....
Let us know what you decide to go with!
Rangerroy
Don't know what your price range is or if you like chassis, but Oryx (off shoot for MDT) has a good chassis that you can order for $399. Direct replacement for Rem 700 S/A (right hand only that I have seen) and it accepts AICS mags. I've got 3 of them so far and have been extremely happy with...
I would double check torque on everything - it may be the primers as others have noted and do a ladder test on the scope, but rail screws, scope mounts, action screws, etc... I would double check them all. Let us know what you find...
I noticed in your post you stated you were in meters, yet you stated yards on the hunt. Any chance you had those causing you a problem along with a possible difference in the ammo you were used to using?? 350 meters is a lot different than 350 yards and depending on what you were looking at in...