RE: Questions about properly sighting my rifles
you may want to try Winchester Supreme Ballistic Silvertips they work great in two of my rifles.
130 grain in my .270 for deer
180 grain in my .300 mag for larger animals ( either silvertips or failsafe for the bigger animals)
I also use their partition gold slugs here in the midwest in my slug gun, they just seem to work, but I guarantee ya someone out there will say they shot terrible in their rifle.
A rifle or slug gun likes what it likes and they can be the same make and model and still like different ammo. Find what they like and you are half way there.
If you suspect a flinch, have a buddy load your rifle, and leave one round out. WHen the empty chamber comes up and you think it is loaded if you flinch when you pull the trigger it will be plain as day to you and your buddy.