torque wrench?

[IWAC]

Watching a Ruger "How-To" video last evening, and the presenter said one sure-fire way to increase/restore the accuracy of the M77 was snugging the front action bolt down to 90 inch-pounds. " About what a "strong man" can do", sez he. AHA, sez ..I, my Ruger hasn't been shooting really well lately.So, you can guess where this is going, right?
I Loosened all action bolts, then turned my Wheeler torque wrench to max...about 60 in./lb., and had at it. I clicked it, then I put a larger screwdriver on it, and attempted to tighten more. No luck! At 77, I guess my "strong man" jumped ship about 65! Nobody I know has inch/pound stuff, so I'm considering buying one of Harbor Freight's inexpen$ive wrenches in order to reach the 90 Ruger recommends. I figure, I will use it at most twice a year, and other torque wrenches are really high priced. So, am I being foolish to buy a lower priced wrench for occasional use?
Thanx

 

[Larry Ashcraft]

I use one on my Harley. Most of their tools seem to be of decent quality for the average guy.

 

[PlayTheAces]

Whether you need one for occasional use or not is something only you can answer. As far as a cheap Harbor Freight torque wrench itself, I have one along with an expensive dial indicator wrench. I've bench tested them side by side and they read exactly the same. I use them both on my Jeep.

 

[redbone]

Does that apply to a 77-44 also?

 

[IWAC]

Does that apply to a 77-44 also?

redbone; I don't think so. The 77-44 is a bolt-action .44 magnum, right? Or is it the lever action? Anyway, the figures I quoted were for my Big-bore Ruger 77. I have in my notes 20 inch/lb for the 77-22, which I would think is a good starting point for the 77-44. Probably should be a bit higher, due to the larger cartridge's pronounced recoil, but that's just a guess on my part, ththers with more experience will probably come to your aid, though. Perhaps give Ruger a call.

 

[stringnut]

Harbor freight stuff can be ok for occasional use. Strongly recommend checking it against a known good torque wrench. I have seen them off enough to cause serious issues. They also sometimes lose calibration quickly. I do not allow them in the Mack Truck dealers shop that I supervise. However, that is a completely different environment than you will be operating in.

 

[Tirod]

90 inch pounds is 7.5 foot pounds. The typical lug nut is 85 to 115 foot pounds and the average male can handle that with a lug wrench parked on the side of the road in a light rain at 2:30 AM.

Inch/pounds can usually be exceeded by light hand pressure on a box end wrench. I'm thinking there is a disconnect between Rugers spec and the need to be a "strong man." Maybe there's some missing nuance of humor.

Torque wrenches have to be calibrated at the factory and most aren't far off. The real difficulty is using them in the field. The torque specs for a specific bolt may be clean and dry in a new assembly, but reusing a rusty one coated in petroleum by products changes the amount of friction as it clamps - considerably. That's where things start going out of spec but the wrench always takes the blame. It's measuring frictional resistance to torque - anything that alters the nominal ideal will change the clamping pressure.

Dirty bolts in oily burred holes can't and won't torque to specs - and be looser than required. It's why engine designers went to "torque to yield" where the bolt is twisted to an arbitrary clock position regardless of the foot pounds reading. Where you and I might stop short seeing 110 pounds on a torque wrench installing head bolts, the engineers would have you go another 270 degrees. For some of us it would seem as if we'd be twisting the head off the bolt and extremely risky. "Just do it" is their motto.

A good wrench is only as good as the bolt and the cleanliness of the assembly. Given that, paying for an expensive torque wrench to sit in a tool box for months at a time doesn't seem to be a good use of the money. I do buy import wrenches because of that, and wont buy Craftsman because the last two have failed with less than a hundred uses on each. One had the head separate across the rachet mechanism and it's replacement disassembled the handle making it useless. There is NO warranty per Sears. I thought my dad was just being cheap using import tools late in life, now I understand it. You can buy an heirloom torque wrench to hand down to the kids, but it likely will cost more to calibrate than it's worth. So, don't bother.

 

[Taurus 617 CCW]

Depending on how many rounds you have through your barrel you may have a copper fouling issue that is contributing to accuracy loss. KG products has a fantastic copper cleaner (KG-12) that I have been using for years. I cleaned the copper out of a customer's gun that had accuracy issues. The groups tightened right back up after cleaning.

If you have a foot pound torque wrench you can set it to 7.4999 or 7.5 which is equal to 90 inch pounds. Hope that helps.

 

[morcey2]

I think they were referring to a strong man with a screwdriver, not a wrench. I've just never seen a torque screwdriver that goes above about 65 inch-lbs. If the action screw is an allen head or torx, a small inch-pound torque wrench would work. If it's a philips or flathead, I'd find a different screw before using a wrench in place of a screwdriver.

Matt

 

[Sunray]

"...foolish to buy..." Nope. Tools are like toys. You can never have too many. Mind you, 90 inch-pounds seems like a great deal of 'tight' for a rifle.

 

[hdwhit]

Tirod wrote:

90 inch pounds is 7.5 foot pounds.

90 inch-pounds is indeed 7.5 foot-pounds as Tirod said and that does not require a "strong man". In fact your stereotypical "98 pound weakling" can do that with a Craftsman torque wrench. Are you sure you read the specification correctly?

 

[Bart B.]

90 in-lbs seems quite a lot to me. Win 70's do best with 60 and Rem 700's 40 to 50.

 

[boom boom]

I thought 90 inch-pounds was high too. But, Ruger factory specifies 95 inch-pounds for the angled front action screw. 30-50 inch pounds on the other two. Some disagreement about the order after the front action screw.

Given that Ruger sells the 77 in some pretty hard recoiling calibers, might explain the relatively high torque specification.

 

[Bart B.]

In my tests bending box magazine receivers, Ruger 77's bent the most with a 50-pound weight hanging on its back end. Maybe that's why the 77's spec'd at 90.

 

[Varminterror]

Appropriate torque wrenches can be had for $25-35 and will work fine for the average gun owner. I've been using the same one for about 18yrs, and have done over a hundred block & bed jobs for Ruger rifles with mine for customers, let alone how many times I tore my own rifles apart with it. I picked up another one a few years ago when I couldn't find my old one after I moved, pretty sure it's a Husky brand, and paid $34 for it if I recall. Not as pretty as my old one, but it works just as well. Found my old one, now I have two. Can't complain about that.

When you take it apart to manage your torque settings, ensure your mag box is free floating as well - that tends to be the 3rd most common NEEDED improvement for Ruger M77 Mark II's and Hawkeyes (first being trigger, second being action torque, fourth being free floating the barrel).

 

[Varminterror]

90 in-lbs seems quite a lot to me. Win 70's do best with 60 and Rem 700's 40 to 50.

I thought 90 inch-pounds was high too...

Given that Ruger sells the 77 in some pretty hard recoiling calibers, might explain the relatively high torque specification.

The angle of the screw is what explains the high torque spec compared to other models.

90in.lb. in a Ruger is equivalent to ~64in.lb. in an action with a perpendicular action screw like a Rem, Win, or Savage (or anyone else's rifle). 90 x sin(45) = 63.6in.lb. straight down, and 63.6in.lb. rearward.

 

[boom boom]

Thanks Varminterror, that makes sense.

 

[redbone]

redbone; I don't think so. The 77-44 is a bolt-action .44 magnum, right? Or is it the lever action? Anyway, the figures I quoted were for my Big-bore Ruger 77. I have in my notes 20 inch/lb for the 77-22, which I would think is a good starting point for the 77-44. Probably should be a bit higher, due to the larger cartridge's pronounced recoil, but that's just a guess on my part, ththers with more experience will probably come to your aid, though. Perhaps give Ruger a call.

Thanks, IWAC. That makes sense. The design of the 77-44 is very similar to the 77-22.

 

[DRYHUMOR]

Seekonk has good torque wrenches. An adjustable L type may be the ticket for the OP.

 

[22lr]

If you don't want to buy a larger torque wrench, most auto parts stores have tool loan programs and you can borrow one for free/a very low rate from a lot of stores (or at least I've had good luck with that).