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Posted By: Thumper358 Action screw torque? - 09/06/08

I have a M70 that is pillar bedded..When I bought the rifle, It came with instructions to torque the action screws to 65in/lbs..How important is it to do this?..Are pillar bedded rifles more sensitive to torque?..the rifle shoots about 1 MOA, and I just snug up the action screws..are all rifles torqued to 65?..should I buy the "Fat Wrench"?

art
Posted By: Nessmuk Re: Action screw torque? - 09/06/08
Was down at the mil-surp store in Barneveld last week and found a torque screw driver, with the 1/4" hex end, for $15.00, works like a charm. A needle points to the torque as you tighten it. I already have a 1/4" clicker wrench, but this is cat's ass easy.

I had to ask this question myself once, and wrote it down in my notes somewhere. 65 seems high, but maybe the prev. owner tried different settings and that's what worked best.
Try a search, going back a couple years, using " torque " as a key word.
Posted By: Thumper358 Re: Action screw torque? - 09/06/08

Thanks Corelokt...

I did a search like you said and got some interesting info..65 is high..most piller bedded around 45ish..wood 12-25 roughly..lots of variation but I have a ballpark idea now..

art
Posted By: Ron_AKA Re: Action screw torque? - 09/06/08
Pillar bedded guns should be less sensitive to torque. If they have been done perfectly (and I suspect few are), you should get some force on the stock first, and then you will come hard up against the pillars. After you are hard on the pillars, then no matter how much torque you apply, you will not be changing the force in the stock or the fit of the stock to the action. 40-60 in-lbs is probably fine for most pillar bedded guns. By feel you should find a point where almost no turn produces much more torque. This is when you are "hard" on the pillars. Going past that point is probably all you need.

A simple trick without buying a torque wrench is to weigh your gun. Then choose a wrench for your screws that gives you the torque you want. For example if you have a 8 lb gun and use a 5" wrench then when you can lift the gun with your finger at the end of the wrench (or at 5"), while you steady the barrel with your other hand, will give you 40 in-lbs.

Ron
Posted By: GeoW Re: Action screw torque? - 09/11/08
Ron, you're getting into some souped up arithmetic there, ain't you?
:-)
Geo
Posted By: Ron_AKA Re: Action screw torque? - 09/11/08
It was a good tip from another poster. Makes sense to me, and is a lot cheaper than an in-lb torque wrench. I used the method to measure torque and shot a bunch of groups with two different brands of target ammo in my Savage .22LR. I tried 8, 16, and 24 in-lbs. Groups sizes were best with the 24 in-lbs. The 8 in-lb was 10% larger, and the 16 in-lbs, 45% larger. So it has a significant effect. Someday I need to try a bit more and less than 24 to see if there is any more room for improvement.

Ron
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