Yeah, I almost fell into that mistake, too, Rich.
But still-- I think that following the KISS priciple would involve going with a near duplication of an available factory round. The classic weight for the 7mm is the 140g, hands down. A lot of deer hunters who wanted a little flatter trajectories have appreciated the 130g load, but the improvement on the trajectory is really not much, and gives up some SD.
Keep in mind: The 7mm--08 in 140 is bound to have reduced recoil from the .308 150g at similar velocities. As Rich said, the .308 has a pretty tame recoil. Seriously-- I'm a big guy, but I'm no "Recoil Stud". A 150g .308 is really pretty pleasurable to shoot, so long as you're shooting a rifle with a decent stock. (Note: Ishapore SMLEs are the notable exception! They kick all out of proportion to the cartridge!)
But if you're married to the 120g, I think I'd look for the bullet that is of the strongest construction and gives practical accuracy out of your rifle. Do NOT make the mistake of picking a lighter-constructed bullet just because it's a little more accurate. The kind of rifle you're talking about is not a sniper rifle; you just need "practical accuracy." You don't need MOA accuracy, but you
do need a bullet that can handle a variety of tasks. Looking at the
Nosler Partitions, they offer four 7mm Partitions, but the lightest is the 140.