Not sure where to actually post this. I'll start here.

I purchased the Wheeler F.A.T torque wrench that comes with pre-adjusted torque modules, 15, 20, 25, 35, 45, 55 & 65 inch pounds. Since I'll be using these on scopes, I'd really like to know what each one is actually set at before using them. They say they can be +/- 2 inch pounds. My scope rings are supposed to be 18 in lbs. I'd hate to use the 15 in lb module to find it's 13ish in lbs. Does anyone have a 1/4 drive inch pound calibration tool that can measure actual torque of each module or know of someone or business that can. I'll be glad to pay for the service.

Thanks

FAT comes with a Cal sheet. I've used mine many times, no problem. My approach is to torque the screws, put blue painter tape on the scope touching rings and shoot several rnds of max load. If scope moves, up torque and retest. Just had to get an ADM mount as the Iray one wouldn't hold scope at 20 in-lbs. Just use the FAT and don't worry about it.

My fat modules didn’t come with spec sheets, just a note they can be +/- 2” pounds. Hence the reason I would like to get them checked to know for sure.

When i first started getting into long range, i remember reading about scope installation that often times it's not the exact precise torque that is important. The more important aspect is that all the screws are tightened uniformly. I've had my FAT wrench for about 12ish years and never concern myself with its performance.

However, if you are super into it then a simple widget can be made with some of a known weight. So it would be the weight x the moment arm as measured from the center of the FAT wrench bit. And if you want to really dork out, then you can account for the weight of your widget being applied at the half way point (assuming a uniform cross section). Thought about doing this years ago but never got around to it. Again, i mostly concern myself with being consistent more than the exact torque value.

I use fix-it-sticks and err on the high side. I would use the #20 in your case.

+/- 2 inch pounds is no concern.

I disassemble and reassemble rifles several times a week, and mount and dismount scopes several times a week. Set it for 20 inch pounds and go. If screws break, they were junk screws.

Same, I torque to the high but all my rings are 25lb or 55lb torque specs

I used to do that until I got some Hawke scopes. I have to set them to 18 in pounds or it keeps them from working right.

Thanks everyone, I hear what you’re saying. Unfortunately I’m an engineer with an engineer brain. I sometimes have a small gray area of focus. Things I should leave well enough alone will drive me nuts. Like this😳

My Area 419 scope rings are 18 in lbs. Picatinny rail 20 to 25 in lbs. Mount to rail is 45 in lbs. I’m covered there! Use the 15 or 20 in lbs for the rings and 25 in lbs for the picatinny rail?

Thanks

Thinner score tube, can do that.

419 uses a really 7075 billet aluminum vs 6061, so you are very safe on the high spec Side.

The only spec I might error caution on is rail to action, I like to bond rail to action any way with loctite 380, just because those tiny screws make me nervous with shear direction

I also use thread locker/paint pin on all screws. I’m rough on stuff….. real tough

You will crush a Vortex tube at those torque specs...all of their high end scopes are also 18 in/lb

OP - Most of the ring torque specs should be set by the scope manufacturers not the ring manufacturers....talk to them. I used a Wheeler Fat Wrench for years and bought a Vortex screw driver wrench and lately I've caught myself using it more often. Not saying it's the best but it works...as does the Wheeler. I personally wouldn't worry about it as it's "close enough" but if you want to get it certified: https://www.parktool.com/en-us/our-services/torque-device-repair-calibration those folks are supposed to be pretty good.

You will not crush a LHT, in NF/UM @25 or ARC M brace @ 55.

I can prove it😂🤣😂🤣

The scope on this rifle is GPO 3-18X44 Centuri. I've used 18" lbs on the rings with no issues. I'll probably go with the 15" lbs torque module on the rings.

Saw where they warranted a scope tube from a guy last week and told him his erratic tracking behavior was due to over torqueing and they knew this because the tube was bent. I'd say it's not the first nor last rifle item you've likely trashed

They do make electronic torque gauges that will give you a readout accurate to +/- 1%, but they ain't cheap. We had one at a previous employer that the guys in our controls and instrumentation shop used quite a bit. IIRC it cost somewhere around $2500 and that was about 2005. It would probably be closer to $3K today.

I have no idea how accurate they are, but ebay has one of these that might work for you.

Disassembling other people's rings, last week 60 in/lbs wouldn't break loose the screws in the ring caps.

I’m done with scopes or rings that can’t take 25lbs… I don’t like my stuff moving, no way they bent a scope from over torquing, that’s from falling on bell housing…. I know I did it to a Luppy.

Now what scope took a 12’ drop and held zero…. NF. Unintentional experiment 10 days prior to sheep hunt 😂🤣😂


You need another LHT?

Just out of curiosity what does GPO recommend? I’m 80% sure those are LOW scopes

Bet scope didn’t move 😂🤣😂

I have the 419 rings and went 20 on an XTR II. No issues.

I just got a response back from GPO. They recommend 18" lbs.

Big Fitz learned that when you apply Locktite, it lubes the threads. Which creates more rotation than the torque wrench is set for. Since you want to get over head high in the weeds, set your wrench for 15 in/lbs and apply low strength Locktite to the screws. You might be 15.5, 16, 16.5, 17, 17.5, 18, 18.5, 19 in/lbs. Or infinite in between those values.

Are you going to have the screws Rockwell hardness tested prior to installation?

Now now let’s not get testy! A lifetime of prove/disprove is how my mind works. I function on known data, or solving for the unknown.. It’s tough habit to break and look past. I’m sure when you’re setting up a lathe project good enough is not good enough for you.

Just messing with ya. No meanness intended.

Start centering a barrel with a .000" dial indicator. Then move to a .0000" dial indicator. Once that second indicator shows no run-out let's start cutting. I'm not looking for a dial indicator that reads .00000". The one before it is good enough.