How important is a torque wrench for scope mounting?

[bp7178]

First time I ever used a torque wrench was the first time I ever left ring marks.

Go figure.

[dentron]

I've used a Wheeler Fat Wrench for scope mounting with good results. You can occasionally find them on sale for $30ish, probably not a necessity on anything less than a precision rig, but still money well spent to *know* it was done right.

+1
I like having the tools to do it right. Why spend $1000+ on a scope and mount and cheap out on the install. I bought the fat wrench and find myself using it more than I thought I would.
Also in regards to torque wrenches, they are a precision instrument. Cheap and precise don't go together.

BUT, if you don't see yourself switching scopes a lot, just use some blue or purple loctite and hand tighten plus another 1/4 turn.

[markm]

Put some blue Loc-Tite on it, snug it up and turn it another 1/4 turn. It will be OK.

Yep. In many cases, torque specs are there so some lunatic doesn't go gorilla on a fastener.

[JBecker 72]

You guy's knocking Harbor Freight torque wrenches might want to change your tune after doing some research on them. There have been a few tests where they were as accurate as a Snap On. Overall they perform pretty well for what they cost and are certainly capable of giving an accurate reading. Not something a pro is gonna want to use everyday, but for a weekend wrencher who rarely uses one they are fine.

http://www.hotrod.com/how-to/additio...rench-testing/

[Ryno12]

I can guarantee you that I've seen so many failures with all sorts of Harbor Freight tools that regardless of what any member on a gun forum says, you'll never convince me otherwise that it's anything other than complete trash.

I use real tools, professionally, every day for a living. I know junk when I see it.

[Hochsitz]

I have a $40 Husky Home Depot automotive torque wrench that several people have told me "oh those cheap ones are way off". Then one day I had reason to calibrate it and determined it was spot on. I clamped the square driver in a vise and started hanging weights on the handle, targeting an exact distance from the driver. If you have any doubts about a particular wrench, find a good scale and perform the same test. Torque = force x distance. Just make sure you're using inches and pounds for an inch-pound wrench.

As far as needing a torque wrench, the goal is to get it tight enough that the friction on the fasteners, scope and mounts is sufficient to keep everything from moving under vibration and recoil. If you go too high you'll start to dent your scope and damage the mounts themselves where the head of the screw bottoms out (counterbore or countersink). If you keep going the smaller #6-48 fasteners will begin to elongate above 40 in-lbs and finally snap around 50 in-lbs. I've never broken a #8 screw myself. Some fastener manufacturers recommend a torque spec that is 65% of the failure torque of the fastener. That's great for the fastener but doesn't necessarily take into account what that force is doing to the assembly. In my experience something in the low to upper 20's in inch-lbs on fasteners is just fine, erring on the low side for #6's, high side for #8's.

I have access to torque wrenches if I want them but have used them enough times I have what I feel to be a calibrated wrist. Thus on almost all of my gear and other people's stuff I've put together I just go to German specs: gutentight. If I had my own business where I was selling high dollar rifles to customers, damn right I'd use a torque wrench on every fastener just to cover myself for liability. Plenty of people have told me you HAVE to lap your rings, HAVE to use this mount or that wrench, but I've slapped rifles together and had them shoot dime sized groups with factory ammo so what does that tell you? So at least try a wrench once to get yourself an idea what you need and then decide for yourself if you need it. To the person that asked, yes the 3" wrench that came with your mounts is perfectly adequate to get the needed torque. There's a reason it's that short.

One more thing, if you're using bolt-on mounts on your picatinny rail and want to have good return to zero, a torque wrench can help with that. Nothing will fix a hunk of crap getting under your mount or a dent that happened while the mount was off but all things being equal, ensuring that the torque is the same can help immensely. It's no guarantee so if I'm going to go shoot a critter I will not settle for an unverified mount/scope/rifle assembly. Heading to the range to punch paper? Who cares.

[JBecker 72]

I can guarantee you that I've seen so many failures with all sorts of Harbor Freight tools that regardless of what any member on a gun forum says, you'll never convince me otherwise that it's anything other than complete trash.

I use real tools, professionally, every day for a living. I know junk when I see it.

Oh I agree. I'm just saying for a $30 torque wrench that will rarely get used, they are accurate.

[MBtech]

I can guarantee you that I've seen so many failures with all sorts of Harbor Freight tools that regardless of what any member on a gun forum says, you'll never convince me otherwise that it's anything other than complete trash.

I use real tools, professionally, every day for a living. I know junk when I see it.

Same here, junk is junk no matter how often it is used.

[Eurodriver]

Thanks for the info everyone.

I tightened the ring screws with my fingers making sure the ring gap was even on both sides, and then tightened with the L Key using my thumb and forefinger.

I'm going off overtight being worse than undertight, and a .22 not having much recoil.

I am really only concerned with the base screws, because that torque wrench must have put a ton of torque on them. There's just no way it was 20 or even 30 in-lbs. Will that affect accuracy? (One of the screw heads rounded out, but they are all tight, relatively equally torqued, and intact) I am just concerned the action may be torqued to "align itself" with the screws?

[MBtech]

I think you should be fine as long as everything is tight and stays tight after setting your zero.