“Torque” has a fancy definition that only engineers understand. But for practical purposes, I consider it a measurement of the turning force applied to a tool in order to tighten a bolt or screw. That makes it a big deal in the gun world because threaded fasteners exist everywhere, and they all perform best within a narrow range of torque specifications. Most gun owners don’t get too involved in what those specs are until they start mounting scopes or tuning rifles for ultimate accuracy.
The lack of proper tools for scope mounting can result in stripped screw holes, buggered heads, or screws so tight they’re impossible to remove with normal tools. I’ve done all of those myself, but my goofs stopped when a torque wrench came to live on my workbench, and I wouldn’t be without one now. Mine is marketed by Wheeler Engineering and is called the FAT Wrench. It functions like an ordinary interchangeable bit driver, but is adjustable to produce anywhere from 10-65 inch-pounds of torque.
The FAT Wrench is adjusted by pulling down and rotating the rear ring on the driver’s handle. A sliding pointer indicates the torque setting and the factory claims accuracy of plus or minus 2 inch-pounds. Instructions with the tool give recommended settings for a variety of gun fasteners and emphasize the tool must be reset to zero when not in use. Doing this takes the tension off an internal spring and no doubt maintains consistency of the tool. It’s easy to forget to do this, but once you’ve used the wrench a few times, it becomes automatic.
The FAT Wrench is a must-have tool for DIY gunsmithing.
My FAT Wrench has proven to be an invaluable tool for scope work, especially when securing ring screws. Using it, I’m assured of getting my rings tight enough to prevent scope movement without over-tightening. One knowledgeable shooter I know claims that over-tightening ring screws can cause a scope to shift zero randomly and ruin accuracy.
I’ve also taken to using my torque wrench to tighten the action screws on my most accurate rifles, including rimfires. My testing has shown that rifles can shoot more accurately when the action screws are set to one specific torque level. A test I recently ran on two rifles showed that one shoots best with both screws set at 20 inch-pounds. The other liked 35 inch-pounds by a significant margin. Some shooters have reported results like these can be refined further by experimenting with different torque settings on the front and rear screws. I haven’t gone that far myself, but it’s on my list of things to try.
Both torque wrench uses require driver bits made for gun work, and the FAT Wrench comes with a basic selection. For more bits, Wheeler Engineering also makes conventional screwdriver sets with bits that fit interchangeably. Although most hardware store hex shank bits will fit, I recommend using bits specifically made for gun work, like Wheeler’s. Their screwdriver sets are of good quality and reasonably priced.
A driver set made specifically for firearms is a worthwhile purchase.
Having a conventional screwdriver set on hand expands the uses of a torque wrench, and you can’t own too many different bit sizes or types. So far, I’ve needed varying sizes of Allen, Torx, slot and Phillips bits to work on my firearms. High-quality firearms and optics cost a lot of money; a key step to protecting that investment and getting the most from your equipment is using a torque wrench and a gun-quality driver set.