Rifle Scopes Is my scope going to be okay?

[knotty]

Alright, so i have a remington 700 .308 and i had mounted my Leupold MK4 ER/T in a NEAR Mfg alphamount base/rings, which is the base and rings together in a one-piece format. I torqued my scope rings to 21 in/lbs +/- 4% from the borka torque wrench, so between 21.84 and 20.16 in/lbs. I shot 4 rounds then unmounted the scope to change eye relief and i saw a tiny silver horizontal line from where the top ring was cut in half. I felt it and i felt the smallest little bump. It feels like if you take a sheet of standard printer paper, lie it flat on a table and feel the transition from paper to table. Near mfg told me to torque the rings from 18-25 final. I had a perfect gap between the top and bottom rings. The silver mark looks like a fracture line. The other side of the rings shows the same marks but less, no bump. I know this probably dictates that i over-torqued the fasteners, but i was well within the final torque specs set out by Near. Does anyone know if this will affect the scopes function and performance.
Sorry for the long story. Thanks for any future help.

 

[bigwheeler]

Re: Is my scope going to be okay?

You shouldn't have had any problems with the price of NEAR's stuff. I would be contacting them. Shouldn't have hurt the scope any more than cosmetic.

 

[knotty]

Re: Is my scope going to be okay?

I contacted Near and he told me he would look at the base and offer a full refund or repair. He told me my scope will be fine, so all is well. Very good business to deal with, one of the best.

 

[sirhrmechanic]

Re: Is my scope going to be okay?

Was your wrench foot pounds, inch pounds or inch ounces...

Near products should not break if torqued w.in specs. But I see lots of people who don't look at the details of torque spec's and torque inch ounce screws to foot pounds, etc.

The good news is that I am sure NEAR will stand behind their rings.

Cheers,

Sirhr

 

[knotty]

Re: Is my scope going to be okay?

It is one of the borka torque wrenches, so it is in in-lbs. My guess is the calibration might be off causing over torque.

 

[kortik]

Re: Is my scope going to be okay?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: CanTarget</div><div class="ubbcode-body">It is one of the borka torque wrenches, so it is in in-lbs. My guess is the calibration might be off causing over torque. </div></div>

Sorry to hear about your trouble, but Borka torque wrench can not have this issue with calibration, by design.

However, over torqueing may happen because of the operator's error. Same hex hole (socket) on one side of the driver arm limits torque to 21 inch-lbs, and to 50 inch-lbs. on the other side of the driver arm. If the operator did not not follow instructions in user guide and mounted driver spindle (bit holder) from the wrong side of the driver side, it is possible that the operator was in fact applying 50 inch-lbs. instead of 21 inch-lbs.

If you have doubts what is the correct setup procedure, please carefully read the user guide. Also, you're very welcome to contact me directly, and we can go thru correct driver setup procedure together.

Other thiings to consider:

1. Torque is just a practical/relative measure of clamping force, created by the fastener when it is being torqued. If threads happen to have any kind of lubricant on them (threads are not completely dry), the same torque will generate VERY DIFFERENT clamping force for dry and lubricated threads. The difference can be HUGE, anywhere from 25 to 75%, with clamping force being much higher for lubricated threads. For example, oil, wax, loctite and water are all lubricants, just with a different behaviour and different coeficients of friction, according to the basics of tribology.

2. While I'm not a forensic expert on scope tube marks, their orientation on your scope tube, as described, appears to me a be an indication that scope ring O.D. is a bit smaller than scope tube O.D. I could be wrng on this one, but it may be good idea to consider such possibility and check it out.

Boris
Borka Tools

 

[knotty]

Re: Is my scope going to be okay?

Thank you for address my issue directly. I was talking with the guy from NEAR and he was saying that the torque values can change if you are applying a force down onto the fastener as your are trying to torque it, as well as if you are not applying a perfectly parallel force to the fastener as you torque it. He told me it cannot be undersized rings because he machines the rings to very tight tolerances and also he has the mechanical drawings from leupold for my scope in use.
One thing that i just remembered that could have possibly caused it was i had an inexperienced user shoot my rifle and they wore the scope eye piece in the head during recoil. Might that have caused the marks?

 

[Jon A]

Re: Is my scope going to be okay?

It's much more likely the scope tube was a few thousandths oversized and just scraped a bit on the sides as it was torqued into the mount. The outside diameters of scope tubes don't seem to be held to very tight tolerances. If that's what happened your scope is fine.

 

[kortik]

Re: Is my scope going to be okay?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: CanTarget</div><div class="ubbcode-body">Thank you for address my issue directly. I was talking with the guy from NEAR and he was saying that the torque values can change if you are applying a force down onto the fastener as your are trying to torque it, as well as if you are not applying a perfectly parallel force to the fastener as you torque it. He told me it cannot be undersized rings because he machines the rings to very tight tolerances and also he has the mechanical drawings from leupold for my scope in use.</div></div>

I do not see how applying the down force to the fastener, typically just 2-4 pounds normally required to keep Borka torque driver engaged with the fastener while applying torque, can do anything to change the torque, which, after being applied, generates hundreds of pounds of clamping (axial) force for the same fastener. "Parallel" force is something that is provided by design by any decent torque tool, not just Borka. And in regard to his remarks about tolerances - occasional out of tolerance machining, particularly in mass prodution, happens all the time, and is more likely to occur is cases when "tight tolerances" are required. Then it all depends what quality control procedures are being used to stop none-compliant parts from being sent out...

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: CanTarget</div><div class="ubbcode-body">One thing that i just remembered that could have possibly caused it was i had an inexperienced user shoot my rifle and they wore the scope eye piece in the head during recoil. Might that have caused the marks? </div></div>

I do not think it is probable. In general, when mounted correctly, scope should not move under recoil, which momentarily applies axial force to the scope, with the value close to 300 times the weight of the scope (typical value for 30-06, .308 meduim weight rifle, per available sources of info). If somebody gets hit in the eye with the force enough to move the scope/make marks, it would likely severely injure or kill this somebody.

Boris
Borka Tools

 

[buckey]

Re: Is my scope going to be okay?

I used to use Near rings but they left hellish rings marks on my scopes even when torqued to proper spec - never found the cause??

I switched to NightForce Ultra-Light & Seekins rings - no problems what-so-ever now!!!