Torque Wrench For Scope/Base Mounting

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I have a 3/8" drive inch-lb torque wrench that ranges 20-200 inch lbs. If I get a 3/8" drive socket that will fit the appropriate screwdriver bit, can I use this for scope mounting or will the fact that I am inserting a screwdriver bit into the socket and then the socket connecting to the wrench cause the torque applied to be over or under the set amount. I think it will work correctly, but am curious what the knowledgeable folks on NES think. Thanks for your replies.
 
You will be fine.... only concern is how accurate your torque wrench is on 20-35" lbs.
I have a torque screw driver that runs 10-50" lbs . It's easier to use than my snappy 1/4" torque wrench.
 
I agree with max1911. You'll be fine, so long as the wrench is accurate. If you are torquing to only 25in-lbs you are at one end of the wrench's scale and won't be as accurate as more in the middle of its range.

If you have a scale for weighing fish you can check it though. Torque is simply length times force. Put an adjustable or 3/8" wrench on the 3/8" square drive of the torque wrench. Hook the fish weigher through the hole in the adjustable wrench and pull at right angles to the adjustable wrench. The length of the wrench times the pounds of pull = the torque. Hopefully your torque wrench agrees.
BTW, measure the length from the center of the wrench's hole to the center of the 3/8" square drive.
 
I don't have a fish scale, but I do have a trigger pull gauge (not digital) that measures in lbs and oz. I'm not sure how accurately I could pull on that, but I will give it a try.

As to the Wheeler FAT wrench Rob mentioned, how accurate are they? I have read a few reviews and some are not very good.
 
Don't even bother...finger tight...then snug...then snug with a wrench but don't crank it. This isn't rocket science (not meant to sound condescending, but I've never used a torque wrench and have never had an issue)...invest the money you save in a good picatinny mount level to make sure your reticle is straight and true with a plumb Bob on the other end (or a verifiable vertical/horizontal surface). Good luck.
 
It will change the torque only if it makes the wrench longer or shorter.

For example, if you attach a dog bone wrench/adapter it must be at a 90 degree angle to the wrench for the torque to remain the same.
 
If you live near Hopkinton you are free to borrow mine.

Thank you for your generous offer, but I moved out of Mass July 2015 to a much warmer and free southern state. I did live fairly close to Hopkinton and was a member of the Hopkinton club for about 28 years.
 
From the instructions on one of my scope mounts for tightening with out a torque device.
Evenly tighten down all screws, final tightening should be done with the wrench provided. With the short end of the wrench between thumb and index finger tighten screws evenly... I will try and find the instructions.
 
In most cases the only really important thing is to get the screws all tightened about the same.
To answer your original question, on something that requires inch lbs you are not going to twist any adapter that you use. You will be fine. On ft lb stuff a crappy extension can impact torque readings if they twist
 
I don't have a fish scale, but I do have a trigger pull gauge (not digital) that measures in lbs and oz. I'm not sure how accurately I could pull on that, but I will give it a try.

As to the Wheeler FAT wrench Rob mentioned, how accurate are they? I have read a few reviews and some are not very good.

The Wheeler FAT wrench is more or less the standard for firearms related torque wrenches. I have one and have never had any calibration issues with it. Like most torque wrenches, it is important to store them at the lowest torque setting to keep them accurate. I think they run around $50 on Amazon and that includes all the most common firearms related bit sizes.
 
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