Yes the Mag is short Rem 600Those guns I have one too. They are 9 twists. So 120 are your best and mag box limits you, I would pit a whyatts box in it for the newer longer bullets. Good luck..
Just about any bullet in that range. Sierra, Hornady and many others. Flat base is fine, boat tail is fine.got a 660 in 6.5 mag.what do you fell is a good 100 or 120 grain bullet for deer.the max range will be about 200 yards for this gun in the area i want to hunt in.