Torque specs for mounting scopes

[Texas]

I recently bought a torque wrench just to see how much I was applying to the screws when mounting scopes. I've been mounting them for over 20 years the old fashioned way but figured I'd give this a try. What's interesting is that I called Leupold and they recommended 28 pounds for tightening the top ring. I called Sightron and they recommend only 18. This is definitely looser than I'm used to doing it. Anyone else using these tool?

 

[Toby Bradshaw]

I recently bought a torque wrench just to see how much I was applying to the screws when mounting scopes. I've been mounting them for over 20 years the old fashioned way but figured I'd give this a try. What's interesting is that I called Leupold and they recommended 28 pounds for tightening the top ring. I called Sightron and they recommend only 18. This is definitely looser than I'm used to doing it. Anyone else using these tool?

You might want to clarify that this is INCH-pounds.

 

[M-61]

INCH POUNDS.....and did you a purchase an INCH pound torque wrench.
My guess is it will not reach 28 FOOT pounds ...it will snap.

 

[Texas]

Yes it's inch pounds.

 

[Delfuego]

15-18 inch pounds on my Leupold Mark IV and Badgers.

 

[jepp2]

Dry or lubed? Makes a difference.

I always torque the screws when mounting bases and rings (and action screws also). Realize that torque is based on the fastener size and grade. And torque values are MAXIMUM, it is Ok to torque less.

Leupold recommends the maximum torque value: base screws 6-48 22 in lbs, base screws 8-40 28 in lbs, ring screws 8-40 28 in lbs.

I lap my rings for at least 50% contact area and feel very comfortable torquing rings screws to slightly less than 20 in lbs and have never had any loosen or shift POI. But I tend to shoot smaller calibers under controlled situation where I'm not beating the scope around.

Maximum torque is intended to excessively stretch the fastener.

 

[SG4247]

Follow Sightrons recommendation on their scopes or else....you will crimp the scope tube like i did!

 

[TimP]

When torqueing small screws always put a small amount of lubricant/grease on the back side of the screw head. This will eliminate the chance of the screw binding and causing a false reading.

 

[M-61]

Quote from jepp2
"Dry or lubed? Makes a difference."

Great question. And it does make a difference and always in torque reduction. Quite significant depending on the lubricant, which Loctite is also.
I've had zero luck when inquiring about the torque value given if it is dry or lubed as you said. Basically returning to a machinists handbook to get the value for a fastener based on material and size.

 

[6MMsteve]

15in lbs and stop.... for me

 

[Chief 101]

Leupold tech said 18 inch pounds max, rings and bases...I have had troubles in the past with overdoing it...not any more

 

[M-61]

And those INCH pound numbers are for the rings to the scope NOT for the the bolt securing the rings to the rail (Picatinny rail)

 

[fredhorace77]

Nikon recommends 25 on their scope rings. I discovered that was about 5 more than I normally use.

 

[Jay Christopherson]

I called NF once to discuss some questions and when they found out I "only" torqued my rings to 18 in. lbs, they immediately targeted that as a potential issue. According to the guy I talked to, I needed to be 20 - 25. I still torque all my rings to 18 though.

 

[M-61]

The manufacturer has come up with a specific number for a vast number of reasons none of which I would care to challenge or change. In this case it is 2 inch pounds. A small yet still a 10% change. And they gave you a range 20-25. Which might make up for inaccuracy's in an individuals torque wrench. I'll stick with the makers advice.

 

[Grizz2150]

When torqueing small screws always put a small amount of lubricant/grease on the back side of the screw head. This will eliminate the chance of the screw binding and causing a false reading.

Lock tight thread sealer

 

[Shooter13]

I think the locktite is 222 (purple) and the base is "usually" 40 inch pounds and the rings are 18 inch pounds as a GENERAL rule, I've been using this on NF and March but now that this question has come up I'll double check.
Found this, use at your own risk:
Nightforce Torque Specifications
• Base and Direct Mount™ attachment screws - 25 inch pounds
• Ring top screws - 25 inch pounds
• Ring crossbolt nut - 68 inch pounds
• Ring crossbolt nut for six-screw 34mm rings - 100 inch pounds
• Unimount™, Extended Unimount™ and MagMount™
crossbolt nut - 68 inch pounds
• Refer to recommended specifications on Nightforce accessory packaging

 

[JFrank]

I had to dig for this but if it Varys from manufacture instructions, I follow they’re instructions.

 

[Gb300wm]

I always follow the manufacturers specs, no matter what they say. As you can see, they vary….

 

[Chaotik]

I use Nightforce ultralight rings, and the recommended torque setting for the scope base crossbolts is 68 inch pounds. They recommend tightening the ring cap screws to 25 inch pounds.