Mine also does about 3" @ 100 with mil-surp. I've not shot much factory ammo, but it seems to do about the same with that.
With my reloads, accuracy is a different story. Most of my loads are sub-moa, with a few that consistently hover around 1/2" @ 100. The only difference in my loads is that I seat the bullets out toward the lands. My rifle has a "deep throat", so some of my loads approach 2.90" OAL (that's the max that the magazine will handle), most are between 2.82" and 2.87".
Factory Remington 180 Core-loct do about 3", but the same bullet, at the same velocity, in the same case, loaded to 2.82" (bullets almost touching lands), shoots under 0.75" consistently. I actually like the long throat becasuse it allows me to use heavier, longer bullets without taking up too much case volume.
I've given some thought to replacing mine with one of the new 16fcss (stainless, new type detachable mag) for more rust resistance (I take my Scout with me everywhere, and I'm in AK), if I do, should I let you know? (Although, I really HATE the idea of parting with it my Scout, it's my favorite rifle).
p.s. I used my Scout (308) for moose this year, instead of my usual 300 WM. The moose I shot dropped faster than any I've shot with my 300 WM, and I was able to hunt with a 2 pound lighter rifle, that recoils less, and is easier on the ears. I'm not saying the 308 works better, or one trial even means anything, but I was very happy with the Scout's performance. The 300 WM has been in retirement since the Scout arrived.