PDA

View Full Version : Scope mounts screws breaking



floatinghat
08-21-2013, 01:20 AM
Hoping I can get some help or recommendations;

300 WSM 11 FCNS, 3-10 50mm scope, Burris signiture zee tall rings and Burris XTC steel mounts. I am on instlling my third time. The gun is new, I have taken to the range to sight and couldn't get it to group. After a box of shell I got out my old 700, 06 and shot fine. I looked to see if something had come loose and noticed my from mount was bent up and my Sig Z ring was at an angle. The rear torx had popped it's head and the steel mount bent. Not good but explains why it wouldn't shoot. I broke everything down bought new mounts and reinstalled with pruple locktite. We took a short little family vacation so one am I snuck out to a range. put her on paper at 25 moved to 100 and couldn't hold zero. got a drink of water and checked with the family. I looked very close and the same area and thought the ring looked canted and the base was lifting again. When I got home I took of the scope and sure enought the head snapped of the torx.

Now I am $60 into mounts and $120-$140 in ammo, I still don't have a gun with a scope mounted. I don't have a torque in/lb wrench so I used short end of the torx as my lever when tightening the screws. I am pushing the ring cross bolt forward and snug against the "bar". A currently I don't know what to try next?

JW
08-21-2013, 06:19 AM
I have had some of the zee ring cross bolts break while tightening them
My solution was to get the next larger size bolt at the hardware store and tap out the rings that size
I believe I used 6-32 size bolts
If you do a search on here you should be able to find some posts about this
Another option would be to contact Burris for warranty--first option was the quick route for me and I think I have stronger rings too
I am sure some one will chime in with more suggestions
Sorry for you bad luck
I hope this helps
Jack

Tricky
08-21-2013, 06:43 AM
Get different mounts.

thomae
08-21-2013, 08:23 AM
I would call Burris and see if they can do anything.

I presume you have one inch rings.

It sounds as if you could be over-torquing the cross bolts. They only need about 30 inch pounds.

It also sounds as if you may have some "aftermarket" crossbolts. Burris Signature Zee crossbolts are 6-40 slotted head machine screws.
I purchased a bunch of allen head crossbolt replacement screws for my rings and have not had a problem, but perhaps the torx head crossbolts you have are not good quality steel?

The torx tool that comes with the mounts is for the ring screws that fasten the top of the ring to the bottom.

floatinghat
08-21-2013, 02:34 PM
I was going to contact Burris but figured the delay, and thought I would ask locally (here) first. The torx breaking are torx for the bases to the receiver. However, everything is torx, base to receiver, ring crossbolts, and zee ring screws. I am hesitant just do the same install again (using the two remaining good mounts). I was thinking about turning the front mount around this would allow the ring to bite more between the screws rather than slightly behind the one popping it's head.

I am surprised that the torque and force could not only pop the torx head, but also bent the steel mounts with a scope mounted.

CharlieNC
08-21-2013, 02:54 PM
Are you using a torque wrench or gorilla bar. You can break the torx with just a screwdriver drive if you lay into it!

thomae
08-21-2013, 02:55 PM
I am surprised that the torque and force could not only pop the torx head, but also bent the steel mounts with a scope mounted.

Are you ABSOLUTELY certain you have the correct mounts for your rifle?

If so, bedding the mounting rail might help.

stomp442
08-21-2013, 04:04 PM
A one piece mount may also be a solution, like an egw this way you can still use the two good rings you have.

sinman
08-21-2013, 04:05 PM
If you are bending steel mounts with a 300 wsm you have something wrong. Too long of screws, screws not tight enough, screws over tightened and ready to snap. I would say you are probably using the screws that are for the back of the mount in the front and the ones for the front in the back.

floatinghat
08-21-2013, 04:27 PM
Charlie-Not using my old rugby muscles, but not using torque wrench, using my sensitive side. But I am leaning this way over tight. It's just I didn't feel I had them overly tight.

Thomae-Believe the mounts are correct, they would have shipped the wrong ones twice. I used a light film of Locktite (purple) as a bedding. agent

Stomp-that is one strong thought

sinman-Front and rear mount and torx are the same, the torx don't appear to be bottoming out, I am thinking I might be over tight.

btw, thanks for the replies it's all food for thought.