Want a 6.5 for kicks, but I am old school at heart.
My dad gifted me a Remington 760 30-06 pump that I broke in by shooting 300 rounds of Core-Lokt and Peters ammo through without cleaning. While managing to kill lots of hogs and deer. Fast forward 10 years and I moved out west, learned about shots over 100 yards. Killed 6 elk and two Mulies with core-lokt ammo from 150 to 425 yards. Then, I learned about reloading and how to clean a rifle bore.
Handloaded some Bergers, spent $500 on a Leuopold scope, and decent rings-turns out I have a pump that shoots less than MOA even after 400 shots with no cleaning or "break-in" process.
Don't over think it-shoot a lot, find the animals and put it in the boiler room!