M77 300 win mag tuning.

[detour]

I just purchased a used M77 .300 Win Mag. The gun was only shot a few times and is in perfect condition. I had a local gunsmith work the trigger to a very nice 3 lbs, and but a limbsaver recoil pad on. I but a nice 2.5 - 10 nikon monarch gold scope on it. The gun shoots very well

With barnes triple shock bullets (180 gr), win brass, 73.5 grains of 4831sc with a coal of 3.340 the gun will shoot around .75 inch group.
Nosler 180 gr accubonds with the same load and coal will shoot about 1.00"
With the cheapest 180 gr federal ammo off the shelf it does about .750" group or better. All groups 3 shots.

My big question: The stock is still totally stock with the front pressure and not being glass bedded. Would I improve the groups with removing the pressure on the front of the stock to barrel contact and glass bed the action? Or would it make things worse?

I would like this gun to shoot .5 inch groups with a 180 grain bullet in a good elk busting bullet.

Thank You,

 

[pvtschultz]

I don't have any experience with the M77, but it uses an action VERY similar to the M98 Mausers. With my sporterized Mauser 308, I bedded the front of the receiver and 2" of the barrel which is the common recommendation. The rest of the barrel is free-floating. I can shoot sub 1/2 MOA groups with it but I really need to do my part with the loads and pulling the 3# trigger. I have shot a best 0.23" three shot group, but most loadings are 1/2 to 3/4 MOA.

Going from 1 MOA to 3/4 MOA is pretty easy with a good glass and some minor tuning, but going to 1/2 MOA and below can be an exercise in futility with factory rifles. Just my $0.02.

 

[tek4260]

If the rifle is shooting an honest 1/2" at 100, I would leave it alone. With nothing more than a little more trigger time, you will probably get the groups you are looking for. I have always found the best accuracy with H4831 in the 300 Win and the 300 H&H. I pretty much exclusively use Sierra 165gr HPBT Gamekings. In my Sendero, it will touch 3 all day. In my Pre-64 H&H, it will make 3 shots resemble a .338 hole! Those are my best 2. The other several hundred factory rifles I have owned didn't come close.

Congratulations on grabbing a good one! But, if you ever let it go you will buy several several more and probably won't end up with one that shoots like that. Trust me, been there and done that....

 

[Bucks Owin]

If the rifle stays sighted in week sfter week with your bullet choice, I'd leave it alone too. I had a fairly lightweight M70A .300 Win one time that would group 180-220 gr bullets under 1" but it shifted POI all over the target with different bullet weights. (I never got 150-165 gr to group as well as heavier ones either). I thought I'd free float in an effort to "maybe" help that. The groups stayed around an inch but the POI wandered even worse, and I eventually traded it off for a different toy that didn't kick so hard, as I could only shoot one or two groups a day with it without starting to flinch some! (Actually, I also had a p64 M70 .338 that was slightly more accurate, didn't seem to kick any harder and wasn't nearly as "fussy" as to bullet weight POI, so the .300 became "trading stock" for a M100 .284 ) I too got best results with 4831 and H-450 FWIW....A great long range caliber if one can shoot it, as you obviously can....

 

[Digger]

I've got to same I'm with the majority on this. I wouldn't touch a thing. It sounds like you've got a winner.

I've been working with 77.5 grains of H4831SC in the same rifle. I am shooting 150 gr. Partitions loaded to 3.38 COAL. It shoots honest 1" groups at 100 yds (best was 0.76") and I have no plans to touch it. Its a completely stock gun and I am very content to get 1" groups out of a hunting rifle.

 

[detour]

Thanks Guys, I think I will leave it alone an give it more trigger time.