Nightforce Ultramount does not sit parallel to Upper

[Regal2800]

I have a Nightforce Ultramount (20moa Cant) on my AR10 that I am leveling my ATACR. nightforce calls for 100 in/lb on the mount bolts. With roughly 40 in/lb the mount and the upper are perfectly parallel with each other. But I noticed that once I torque to the full 100 in/lb nightforce calls out, the mount is no longer level to the upper. almost as if the mount torqued itself few degrees in one direction.

is this a common issue with scope mounts? Are some mounts more prone to this than others? Any suggestions on what can be done?

Unless I can figure out a solution, I guess im going to have to choice but to level the scope to the mount and not the rifle.

 

[TonyAngel]

What torque tool are you using? Is your rail in good shape?

 

[XLR308]

I have a Nightforce Ultramount (20moa Cant) on my AR10 that I am leveling my ATACR. nightforce calls for 100 in/lb on the mount bolts. With roughly 40 in/lb the mount and the upper are perfectly parallel with each other. But I noticed that once I torque to the full 100 in/lb nightforce calls out, the mount is no longer level to the upper. almost as if the mount torqued itself few degrees in one direction.

is this a common issue with scope mounts? Are some mounts more prone to this than others? Any suggestions on what can be done?

Unless I can figure out a solution, I guess im going to have to choice but to level the scope to the mount and not the rifle.

Just out of curiosity you are only placing the mount on the reciever pic rail section and not spaning from the reciever to the handguard rail correct.

 

[Regal2800]

The top rail is JP Rifles and its mint condition. And yes, mounting to the upper only, it is not touching the barrel guard.

I believe the torque wrench is a gear wrench, but they are built in china so it's possible it's not calibrated properly...

 

[XLR308]

The top rail is JP Rifles and its mint condition. And yes, mounting to the upper only, it is not touching the barrel guard.

I believe the torque wrench is a gear wrench, but they are built in china so it's possible it's not calibrated properly...

Do you have any pictures ?
That might help you get some better info or easily pinpoint a possible cuase of your issue.

 

[MitchK]

100 in/lbs seems high. My NF mount calls for 68 on the cross bolts. Maybe a different model? Idk

 

[srt-4_uk]

100 in/lbs seems high. My NF mount calls for 68 on the cross bolts. Maybe a different model? Idk

If its an Ultramount as stated in the title, 100in/lb torque spec is engraved on the mount.

 

[XLR308]

According to NF Ultramount torque specs
Cap screws 25 in lbs
4 screw cap cross bolts 68 in lbs
6 screw cap cross bolts 100 in lbs

The issue I am seeing is there are only 4 screw cap ultramounts, the six screw are ring sets.
You really need to clarify if it is a ring set, otherwise I it's the for screw cap ultramount you might have possibly damaged it.

 

[Regal2800]

Attached is a pic of my mount. I will try to get some pics of the actual rifle tonight. But 100 in/lb is clearly inscribed on the top of the mount.

 

[71firebird400]

According to NF Ultramount torque specs
Cap screws 25 in lbs
4 screw cap cross bolts 68 in lbs
6 screw cap cross bolts 100 in lbs

The issue I am seeing is there are only 4 screw cap ultramounts, the six screw are ring sets.
You really need to clarify if it is a ring set, otherwise I it's the for screw cap ultramount you might have possibly damaged it.

He said it's a 20 MOA mount, so we're not talking about a set of rings. The ultramounts are engraved with the torque spec; and 100 in/lbs is correct for the 1/2" cross bolts.

I would take photos of the install and contact NF. Their customer service is excellent.

 

[XLR308]

He said it's a 20 MOA mount, so we're not talking about a set of rings. The ultramounts are engraved with the torque spec; and 100 in/lbs is correct for the 1/2" cross bolts.

I would take photos of the install and contact NF. Their customer service is excellent.

I found a picture that finally stated that, and yes I know the torque specs is Lazer engraved on the mounts but all the info for torque specs I could dig up didn't state that.
Doesn't matter chances are he doesn't know what he is doing anyway and I know better than to waste my time on shit were someone starts a thread as a first post and then goes dark.

 

[TonyAngel]

He probably realized what he did wrong. Maybe had the clamps upside down.

 

[XLR308]

He probably realized what he did wrong. Maybe had the clamps upside down.

The world may never know or care.

 

[Regal2800]

I spoke to nightforce, they had no idea. I haven't had a chance but I got a different torque wrench and will re try things things weekend.

 

[Regal2800]

I re did the entire setup. used a different torque wrench and the mount is definitely offset clock wise .2 degrees to the upper. it might not matter but the scope mount is definitely not level to the upper. It's a slight amount so I wonder if people are not aware of this issue? I guess once you torque down on these mounts there will always be some flex in the system making it very difficult to get them exactly parallel to each other.

 

[TheOE800]

That’s what windage dials are for?

 

[Nik H]

I've never exceeded 85 in-lbs on cross bolts for mounts like this. Badger C.O.M.M. mounts are specified at 65 in-lbs.

 

[roosterpig]

100lbs is a lot. I’m not saying it’s wrong, it’s just a lot.

OP, I’d reach out to NF and get their feedback.

Just thinking out loud, what’s .2 deg? 12min? About a foot at 100. I’m sure I’ve missed some linear/arc conversion somewhere while thinkin in generalities. Just trying to justify in my head what the true impact will be to the misalignment, if you’d call it that. Let us know what you dig up.

 

[kl3309]

I re did the entire setup. used a different torque wrench and the mount is definitely offset clock wise .2 degrees to the upper. it might not matter but the scope mount is definitely not level to the upper. It's a slight amount so I wonder if people are not aware of this issue? I guess once you torque down on these mounts there will always be some flex in the system making it very difficult to get them exactly parallel to each other.

Your rail could be out-to-spec (actually more likely than the Nightforce interface being out). Compare to this drawing:

If it is grossly undersized, you can shim the angled point on one side of the rail, or find a split-mount that clamps evenly from both sides.

 

[Makinchips208]

Here is a nightforce mount. Certainly says 100 inch pounds.

It is mounted to a nightforce rail. There should be a gap between the top of rhe rail and the bottom of the mount, only contacting on 45 degree angles.