screw torque for mounting scope base

[MapMan]

I have a DNZ one piece scope base to mount on a Browning X-Bolt. Info on ring torque 25 in/lbs; however, nothing on mounting the base to the rifle. I've tried Browning, Brownells, random internet searches - nada. Brownells referred to a engineering reference book for all the torque values by specific type mounting screws. Brownells reference site within their discussion is no longer available.

I've also tried to get info via gunsmith references and either it doesn't exist or I'm not finding the references.

The only info I have to go forward with is the screw is #8 hardened steel. It is a hex-head allen wrench screw with hole in the top.

Any advice/info will be greatly appreciated. I'm more than willing to buy such and engineering reference manual if I can find such a critter.

MapMan

 

[ColtPythonElite]

Blue loctite and snug just so has always worked for me on base screws.

 

[Jackal1]

When you use a drop of blue loctite the fluid acts as a lubricant and reduces the screw thread friction and increases your preload compared to a dry torque. (The screw is torqued tighter than you think).

Without cranking the math numbers again, I recall the end result was that you put 1 drop of blue loctite on the screw thread and you gently screw in until you meet mating resistance. As soon as you feel a solid stop, STOP. Do not crank down or you'll mangle aluminum threads. With steel threads you might be able to push your luck and snug it down a smidge tighter but I don't think its necessary.

 

[TTundra]

anywhere from 22-25 inch pounds on the base, and loctite it. If you call DNZ, they will give you the numbers as well, Ive had to do it a few times.

 

[Storm]

I use DNZ GameReapers on several rifles. I used a 25# dedicated torque wrench (from Brownells) and have never had any of the screws loosen even without using Loctite.

 

[MapMan]

Mounting screw torque.

Thanks for all for the advice. The HighRoad members are the best.

 

[Charley C]

MapMan said;

Quote; "I have a DNZ one piece scope base to mount on a Browning X-Bolt. Info on ring torque 25 in/lbs";

MapMan: 25 inch/lbs? I own an 18 inch thickness planer that has a spiral cutter head; the cutte rhead has either 6 or 8 rows of 5/8 inch square, solid carbide "bits"; each spiral row of bits has about 16 or maybe 18 bits; each one of these carbide bits is razor sharp on all four sides, and each one is held in place on the solid steel, 3 in dia. head by ONE "torx-head" screw, which is app. 5/64 inch. At full speed, (it's rheostat controlled), the cutter head turns at 4,000 RPM; (no lock-tite is used) Each one of these screws holding a solid piece of razor sharp carbide is torqued to exactly 20 inch lbs.! It's absolutely essential that every bit is torqued exactly the same, otherwise if any one bit was "out of alignment" by only a few thousandths, it wouldn't plane a perfectly smooth surface;

It's hard for me to imagine why something like a scope mount would ever be torqued to 25 inch lbs. Just guessing, I'm thinking that the screws that hold my cutter bits on my wood planer may be very slightly bigger in diameter than those used on the scope mount, but I doubt if there is very much difference. If I were you, I would really check out that 25 inch lb. specs as supplied with your mounting. I might mention, since I bought my planer new, I have planed several thousand board feet of white oak and red elm, and I have never had a cutter bit become loose, and so far, I have not yet had the need to turn any of them 90 degrees to get a new sharpened edge. It's really hard for me to think of a single screw in anything that has any more "riding on it" than all of those little screws holding all of those little razor sharp carbide bits.

 

[AKElroy]

For bases, I use 30 inch-lbs with a drop of blue locktite, and 20-25 inch pounds for the rings, no locktite there. I have mounted scopes twice using the DNZ mounts, and these were the weights I used. I go back and forth, end to end, a quarter turn at a time to ensure that torque is applied absolutely evenly. I think having a uniform tightness aids accuracy as the rifle heats those aluminum bases up, but that is just an assumption.

One issue you may have is that one of the screws is countersunk to deeply for the average hex-bit to reach, so I used my best guess at torquing with the supplied allen wrench. I like DNZ mounts, good choice. Well made, easy to install.

 

[MapMan]

Thanks again. I called DNZ and they said 25 in/lbs and to use the supplied pattern of seating the screws and torquing they show for installation. I intend to start low and slowly increase not to exceed 25, as we do in loading a new cartridge load. I have also read about using blue locktite and how it reduces the thread-screw resistance because it initially acts as a lubricant and the difference in "preload" and dry torque just as Jackal1 stated. I think his advice is very well stated and accurate information.

Next question: My son gave me a Borka Torque Driver for Christmas as I do not have a torque screw driver. I hope that my attached photo is viewable as it will explain more than words. Does anyone have any experience with this device? Comments on use, accuracy, etc.

Thanks again to all. MapMan

 

[TTundra]

Great tool if used right. Read the directions and if you can watch the youtube video by "lonewolfUSMC", he uses one in his mounting videos.

 

[AABEN]

Thanks again. I called DNZ and they said 25 in/lbs and to use the supplied pattern of seating the screws and torquing they show for installation. I intend to start low and slowly increase not to exceed 25, as we do in loading a new cartridge load. I have also read about using blue locktite and how it reduces the thread-screw resistance because it initially acts as a lubricant and the difference in "preload" and dry torque just as Jackal1 stated. I think his advice is very well stated and accurate information.

Next question: My son gave me a Borka Torque Driver for Christmas as I do not have a torque screw driver. I hope that my attached photo is viewable as it will explain more than words. Does anyone have any experience with this device? Comments on use, accuracy, etc.

Thanks again to all. MapMan

You can go to Triad Tactical IN and look it up. It is very simple one to use. I wished I had hard of that before now!

 

[slowr1der]

I also have the Borka wrench and it's excellent imo. The best torque wrench you can buy for this purpose imo.

 

[MapMan]

Again, Thanks to all! MapMan

 

[RainDodger]

Just last night I mounted an EGW rail on a Browning BAR. The instructions with the rail said to use blue Loctite and torque the 4 screws to 20 inch pounds.

 

[MapMan]

I think Jackal1 above has the right idea about prelube and dry torque. It's what I did absent any specific info provided with the one piece mount. When I called DNZ I was told 25 in/lbs but went blank when I asked if that was a lubed torque or dry torgue. It's on and doesn't feel like it's going anywhere. There's an OpticsPlanet video/demo of how to mount scope bases and the narrator used 30 in/lbs. Good luck, MapMan. P.S., let me know how you like that BAR.

 

[ranger56528]

I set my Wheeler at 20 inch pounds on all my bases and scope mounts,seems to work fine for me,I'll wait about 15 min then go back and re torque the base before I put the rings on.

 

[RainDodger]

I bought a Weaver torque screwdriver that looks about like the Wheeler. It came with a certification signed by the tech that shows what the torque values checked out as, through the entire range of the tool.

Bottom line though, I think the one you got is probably the most accurate type to have. Nice tools are a joy to use!