Ruger M77 International .308 reloads

[tfiorelli3]

I just bought a Ruger M77 International .308. I have been very successful in reloading .30-06 w/ a receipe of 180gr bullets, 55gr IMR 4350. However, I can't seem to find a load using 180gr bullets (including factory loads) that produce tight groups for my .308 less than 3 inches at 100yds. Any suggestions?

[TATER]

I absolutely love Ruger Internationals (But, a target rifle it’s not)
3 inch groups at 100 yards is pretty good for an International.
Why the 180 grainers?? I’ll see what I can find in my notes
when I get home.

[tfiorelli3]

I have an abundance of 180gr Core Lokt PSP and hunt deer and bear "drive and post" style in Pocono Mountains, Northeast PA which almost always guarentees a shot at 50 yds or less. I also have been using a IMR 4350 receipe found in an old speer manual but I am concerned b/c it is a compressed load and it does not seem that consistant. I keep seeing the IMR 4895 as the "best" powder for .308, but before I start a wild goose chase I need to gather some good info. Thanks for the reply!

[boltgun71]

I have had good luck using IMR-4895 with 180gr loads in my .308 Win. With 39.0 or 40.0 grains of IMR-4895 under a 180gr Speer SPBT I have yet to get a group larger than 1" in my Rem 700 while load testing. This is with new Remington brass and CCI LR primers.

[TATER]

While IMR-4895 is great powder, you a dealing
with a shorter barrel and That's a big slug, . Look'en at my notes, I was showing pressure signs at 38.8 gr of IMR-4895 and only getting 2250 fps average out of a 22" barrel.

With 42.3 IMR-4064 180gr spitz I was averaging 2480 fps
I would start at about 40.0 grains and work up..I had no signs of
pressure and 2" 10 shot group. (Ruger 77mkII with VXII 3x9 scope)

I never got around to trying Varget but, I would think its another
Good pick with a 180 grain pill.

HTH

[Woolecox]

I get the best results out of my .308 Tactical Precision M40-A5 using Sierra Match Kings in 168 and 175 gr.

I use RL-15 and Varget. Both give the same relults; 5 shots in same hole at 100yrds. 5 shots around an inch at 200yrds. The loads I use are straight out of the Speer loading manual. I have gotten best results by backing down the max charge by about a grain. Speer max loads seem to be pretty hot.

I mainly shoot Lapua brass or Federal "once fired" when I can find it. I trim to length, turn the necks, and uniform the primer pockets. Then run them through Redding neck bushing and seating dies. I seat these bullets .003 in. off of the lands.

Or, I just go out and buy some Federal Gold Medal ammo and get about the same results! For hunting I get best accuracy out of the Nosler BT's or Sierra Game Kings.

I think the Speer Manual has loading info for 180 gr. 308?

[tfiorelli3]

Yes. The manual lists several loads and I have used 48gr of IMR 4350. However, I am not happy w/ the groups at 100 yds (3") and I'm concerned because it is a compressed load. Is 3" the best I am going to do with an 18" barrel or can another powder and/or bullet help me get better groups?

[TATER]

It can be tightened up some I’m sure..
After you settle on a powder-bullet combo you can start playing
with bullet seating and play with the stock tension on that Mannlicher stock.

.308s achieves full-burn in 18”, just not the speed generated
from longer barrels. But, The up-side, its stiffer and harmonics are more forgiving.

You are going to have to play with it.
HTH

[Lawyer Daggit]

I agree the stock may be at fault, I used to own a Ruger International .308 and eventually traded it on a custom shop Rem Mod 7 Mannlicher which incidentally seems to use the same forend cap as the Ruger. I used to find the cap very tight on the Ruger and when the gun was fired without cap groups shrank dramatically.

I would try the rifle with a range of bullet weights- going as light as 130 gr just to see how it performs with lighter loads. We had a cheaply available ammo in Australia called 'Feral Fix' which from memory was basically Australian milspec .308 cases with military powder loaded with a cheap soft point and I seem to remember these shooting surprisingly accurately in my rifle.

The other thing I would mention is that muzzle blast with the .308 International was often quite wicked. In respect to what we call 'recoil', I believe we are in practice talking about three things- the physical movement of the gun in reaction to the gun firing, noise and muzzle blast. I used to find that under poor light conditions I used to react badly to the blast of this rifle and it could cause a flinch.

[Unclenick]

Once you get your stock issues resolved, you'll find 4350 is too slow for either that short barrel or the .308 case. Even a 5% compressed load of it behind a flat base 180 grain Hornady SST only burns about 85% in the short tube, according to QuickLOAD, and doesn't develop full pressure or very impressive velocity. IMR 3031, 4064, and 4895 all do much better.

You will have to work a load up for best accuracy to match your particular chamber and the vibration of your barrel. 3031 will be the most flexible of the three in this regard, as it will burn more completely in the short barrel if you find you have to run light-side loads for best accuracy results. It will also produce the least muzzle blast. The other two can be made to push the bullet a little faster. The starting load level depends on both bullet weight and length, though many manuals don't show it. It also depends on the case brand you use. Winchester cases have about 3 grains more powder capacity than many of the military cases, and are larger than other commercial brands as well, so they will have the least chamber pressure for a given charge weight.

For general purposes, with 180 grain bullets, I would start all the way down at about 36 grains of IMR 3031, 37.0 grains of 4064, or 37.5 grains of 4895 and the bullet seated out near the lands. Fire 3 to foul the barrel, then 3 for group. Seat the next 3 bullets 0.020" deeper, and fire them. Keep repeating this until you find the seating depth that gives you the best group, though you won't want to go too short, or even light loads can start producing pressure signs. If the gun turns out not to prefer a particular seating depth (seldom, so), use the longest cartridge dimension that feeds reliably from your magazine. Once you have that, start working the load charge up .3 grains at a time until you get the smallest group you can, short of seeing pressure signs.