The core-lokt isnt a bullet that i would be sighting in at 300yards IMO. It performs its magic at closer distance's normally. For long range look at the ballistic silvertip or the accubonds....something along them lines!! Good luck!
If you want I can run that through my balistics calculator? When you say sight in for 300yds, you want it to hit at zero there? I suspect the MRT will be fairly high like that. I like to zero hunting rifles with MPBR at a 6" target. Then the farthest the bullet will rise above line of sight is 3" and you'll have a MPBR where the bullet falls 3" below lone of sight.
I have a system I use in Whitetail hunting during the rut that seems to work for me. When I make a mock scrape in the area I wish to hunt I will place a couple of 35mm
film canisters (film removed of course) in the scrape after I have cleared out all leaves and other debris. The film canisters are filled with cotton balls and saturated with doe in heat urine. This keeps the urine from soaking in the ground and can be refreshed on each trip if needed. I will also use the tarsal gland of the buck...