1:10 seems to be the standard and about ideal for 25-06. My Encore shoots everything from 75 to 120 pretty well. Almost any of the cup and core bullets in the 100 -120 range should work on those Tenn. whitetails just fine, without the expense of bonded bullets. I settled on the Hornady 120 HP for accuracy, BC, price and bullet construction. Although it's a HP, it is constructed heavily with big game in mind, it is a good flyer and the tips are tough. Twenty cents a bullet cost between the two types is nothing while shooting at game, but the economy difference encourages a guy to get in more range time while familiarizing with the gun, load, trajectory, etc. I find myself shooting up thirty or so from a 50 count box of premium bullets, then thinking I need to save the last 20 for hunting loads.
I'm figuring you might have got the Stevens with economy being a factor, and I think it's a great value. If so, you will get more satisfaction shooting - and more shooting - with lower cost bullets that will do the job. Save the premium bullet purchases for elk, bears, and once-in-a-lifetime trips.
As far as the difference in ballistics between 100gr. and 120gr., if they are each loaded to standard velocities and zero is 250 yds. the 100's drop 3.00" w/ 1434 ft-lbs energy at 300 yds., and the 120's drop 3.34" and have 1581 ft-lbs of energy. I'd take that additional 150 ft-lbs over a 1/3 inch difference in trajectory!
Elkeater2