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M77 torque specs

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21 April 2013, 01:41
Brice
M77 torque specs
Does anyone know off the top of their head the torque specs and sequence for M77 guard screws? This is the older tang safety model.
21 April 2013, 04:41
dpcd
I have owned several of them; just have a 257 now. I always tightened up the front and rear and left the middle one not as tight. Torque?: pretty damned tight.
21 April 2013, 04:47
ramrod340
quote:
pretty damned tight

dpcd is probably stronger than I am so I have to call it "real" darn tight on the front. Less on the rear and easy on the middle.

I think Ruger calls for something around 90-95"lbs on the front around 45-50 on the rear. Snug on the middle. I've never had the tool to measure mine.


As usual just my $.02
Paul K
21 April 2013, 06:25
pagosawingnut
Ruger specifies 95"lbs for the angled bedding screw. Then equally, you tighten the trigger guard screws tight, alternating between the front and the rear until they are both tight. Then Ruger says to back the front trigger guard screw off 1/8 of a turn. I have found by playing with the torque on that particular screw you can make the rifle shoot better.
21 April 2013, 23:23
dpcd
You might have hit on a million dollar secret here; using the middle screw as a receiver tuning device, tuning the receiver harmonics to make the barrel vibrations more (or less) stable.
BTW, I doubt if I get 95 inch pounds on guard screw. I never measured one. I know I can put 95 FOOT pounds on a Plymouth 340 head bolt.
21 April 2013, 23:57
pagosawingnut
Actually, I have taken Rugers that have shot in the 1" to 1 1/2" range all their life and played with the torque on the front trigger guard screw, adjusting it ever so slightly and brought them in to 1/4 to 1/2" guns. Makes so much difference.....
But it is important to get the angled bedding screw to 95 inch pounds first...