I have a M77MKII in 30-06. I've owned it since 1996 and have shot several thousand rounds with it. I use IMR 4350, Remington brass, Remington 9 1/2 primers and either Sierra, Nosler or Speer 180 grain bullets. My charge weight is around 55.0 to 55.7 grains of powder. I also have a timney trigger in the rifle. But I'm using the original stock. I've never had a reason to change it out. A few years ago, after taking it out of the stock for its semi-annual complete cleaning, my accuracy dropped from 1" to around 1.8 or worse. I bought a torque driver, and reviewed how to set the action screws. I then set the main (angled) screw to 45 inch/pounds and the back screw to about 30 inch/pounds. The rifle subsequently shot into 0.7 inches with 5 shots at 100 yards. My first step would be to go back to the original stock and torque the action in properly. Then use IMR 4350 and a 180 grain Ballistic Tip and Sierra Gameking bullet as a projectile. Velocities will be in the 2650 to 1675fps range, and it will work just fine out to 450 or 500 yards with these bullets. (Speer 180 grain HotCor is also a good bullet for this rifle.) If it shoots in the original stock, then check out the HS stock and think about some upward pressure at the end of the stock, like the original Ruger stock supplies. Some barrels just need that upward pressure and dampening effect and won't shoot well when free-floated. By the way, my Ruger doesn't shoot as well with 165/168 grain bullets as it does with 180 grain bullets. It will shoot them with about a 1.2" accuracy at 100 yards. It does, however, like the Hornaday Amax in 178 grains. Too bad they're not making them any more.
