Weakening guns does not seem to be the best way to balance out the awful, awful other weapon choices.
It's a pretty good way to take two demonstrably overpowered capital-G Guns and put them into their intended hierarchy relative to other capital-G Guns.
We're talking about a very large bullet and a very powerful gun, they seem fine to me.
.308 Winchester bullets usually come in weights that are significantly lower than comparable handgun bullets. They have a lot of propellant flinging them around, but a typical .308 weighs about 170 gr compared to a typical .44 Magnum bullet in the high 200s to mid-300 gr weight range. In the real world, .308 is powerful because it moves fast and it's used for long-ish range shooting because of its ballistic coefficient. I.e. it cuts through air well and has a relatively flat trajectory. It also deals better with body armor than a large, fat handgun bullet because of its velocity and cross-sectional density.
In any case, the sniper rifles were never intended to be such a large jump up from the hunting rifle and certainly weren't intended to outshine the AMR in overall utility.
Energy weapons and explosives are the ones that leave me scratching my head going, "Kinda odd how he just shrugged off that molten plasma I hit him in the face with."
My 2 cents.
I stated a few days ago on the forums that I've added DT bypass to base/OC/MC Energy Weapon ammo types (other than flamer fuel) and tuned a lot of the DAM and ammo consumption values for individual Energy Weapons.
Tuning Explosives is difficult due to how the damage falloff works, but I've adjusted a few of the more problematic Explosives for the patch as well.