Ruger M77 Mark II Problems

[Larry Martin]

Looking for a little help. I have a Ruger M77 Mark II in 7mm rem mag that will not shoot better that 4 inch groups @ 100 yards. I have tried all different kinds of ammo: remington, federal, winchester, hornady etc. Every from 18.00 per box on up to 80.00 per box. Winchester 150 grain super x soft point groups the best but I expect less than 4 inch groups. Hell, my old Remington 700 30-06 is twice as old as me.and still shoots sub moa. I pulled the scope and.mounted on another magnum to check and it was fine. Mounts were tight too. Bore and crown seem to be good also. Anyone else had these issues? Any advice? I guess it may have to go back to Ruger.

 

[scooterj]

Is the barrel contacting the front of the stock? May need to remove some stock material.

 

[headspace]

Is the barrel contacting the front of the stock? May need to remove some stock material.

that is unusual. If there's no problem with the scope or mount and you can't find any load that shoots better than a 4" group at 100 yards, I'd think it needs to be sent back to Ruger. They have awesome customer service. You would have to pay shipping expense, but if there's a problem with the gun that is factory related, they will fix or replace and not charge you.
I bought a government model MK II 22 pistol new and it would not cycle 2 rounds together. This gun came with the test target showing a tight 10 round group. I called, got the shipping info and within a couple weeks got it back, complete with new barrel and it functioned without fail.

 

[Goatwhiskers]

Larry, I strongly suspect you have a barrel contact problem or a bedding problem. Are your action screws tight? So help me I can't remember if that beast has two or three action screws, if three the middle one needs to only be barely snug, the front and rear need to be equally tight. Check to see if after the front one is tight and you start to tighten the rear if the tang draws down, if so you definitely have bedding problems. Glass bedding works wonders. Goat

 

[headspace]

My .270 M77 MKII shot a 3/8" 3 shot group at 100 last time I shot on a rest. With Sellier&bellot 150gr round nose that I paid all of $7 a box for years ago. Glad I bought a bunch then.

I know that rifle to stock fit can decrease accuracy, but a 4" group at 100 seems extreme. I'm assuming you've looked at the bore?
Edit: re read your post. Sorry. If you can't get anywhere,
try calling Sturm Ruger and see what they say. Doesn't matter whether you bought the gun new or not

 

[Larry Martin]

It is a two screw action. Front is tightened to 95 in. lbs and the rear is hand tight per ruger. I did not.think to tighten the front then the rear. Ill have to try that.