Pardini/ Ultradot Torque

Greetings. Long time rifle shooter that is finding the joy of pistol shooting here. Lots of great info. I am sure this has been discussed before, but was unsuccessful in finding with search. I been shooting my Pardini SP Bullseye with open sights past few years. Just bought a Ultradot and set of rings for it from Champion Choice to mount on dovetailed rail. Is there a torque value that is agreed upon for both the rings and the base screws?  After ruining a Weaver T24 a few years ago, I been using a torque wrench pretty consistently when mounting scopes. Thanks.

It isn’t so much damage to the scopes as it is the damage to the screws.  #6 sized screws are not very strong AT ALL!   For base screws it is better to use BLUE  thread locker and torque to 20-25 inch pounds.  Ring screws and scope mounting screws should NOT use thread locker and torque 15-20 inch pounds.

For preventing scope mount screws from moving, I really like VC-3 which is a sticky reusable compound. It's easy to make repairs in the field and put the scope right back on and keep shooting, if needed. It comes in little reclosable tubes, conveniently.

https://www.vibra-tite.com/products/threadlockers/vibra-tite-vc-3-threadmate/

I suggest that you contact the very helpful Katie Zabel (ultradotservice@gmail.com) at UD for advice.

I do not use a torque wrench (maybe that is something I should buy), but try to judge the tightness as best I can. As Wobbley says, stripping the screws is the obvious limit, but I have found that there can be other issues.

The micro-groove on the Pardini's is challenging. The OEM rings that come in the box with a UD are not good. Pardini can sell you their rings (many folks swear by them). There are other options out there. I went with Warne Maxima low rings (sintered steel - low risk of stripping threads) which have a good "bite" on the micro-groove. But, I then found that cinching down the horizontal split rings could easily deform the body tube of a 1" UD. Katie advised me to try to position the rings as close as possible either side of the main body of the UD - and never over the outer ends of the main tubes - there are lens located close to the ends and it is easy to crack them if over-tightening rings.

Some folks prefer other brands of Aluminum low profile horizontal split rings - Leupold and other brands are available. I found Monstrum to be economical and well made. A tip given to me by Chris (Toz35) is to grind down the feet of the rings on abrasive paper so as to create a very sharp "knife edge" on the bottom of the ring mount - that then "bites" better on the micro groove. That trick also serves to reduce the metal protruding below the groove and thus avoid any potential contact with the ears of the bolt when it cycles (it is free to rotate slightly and can easily catch a low slung mount).

I have now switched to Aimpoints on Kodiak mounts, but that is also not trouble free. With the sharp recoil impulse of the 32ACP the mount "creeps" forward. Cinched the screws tight - and then snapped one of the low grade steel screws on the day before a match - Aaarrrggghh - Roddy managed to get it out and supplied me some higher grade steel screws. Tightened them carefully, but it still creeps. I am now working on a restraint device (for the mount - and my temper!). Maybe I should order one of those torque wrenches!

I tighten my rings until I fart then 1/4 turn more

I could have gotten through the day without that image in my brain.

Wobbley wrote:I could have gotten through the day without that image in my brain.

As an Engineer like you that’s my professional torque spec!

From Ultradot:

Mounting Your Sight:    
The rings should be placed as close to the center housing as possible, especially on the objective end of the tube. This will help to provide a mechanical stop and prevent the sight from shifting. It will also help to prevent lens breakage as a result of over-tightening. Finally, when tightening rings, always tighten the bottom ring bolts first and then the top. This will also help to prevent lens breakage. The two ring halves do not need to be touching each other. If you farted, they are, you have almost certainly over-tightened your rings. Lens breakage is not covered by our warranty.

Thanks for all the replies. I tightened them without a torque wrench, to what I felt was comfortable. I shot several rounds through It and have it zeroed.  Seems to be good to go. I do have some of that VC3, maybe will try it next time. Came with a mount I bought, and never used it. Sounds like I may have front ring out too far. I read on another post that it was recommended to have the ring “overlapping “ the Bolt slide handles (or whatever called). Made since to me at the time.

DA/SA wrote:From Ultradot:

Mounting Your Sight:    
The rings should be placed as close to the center housing as possible, especially on the objective end of the tube. This will help to provide a mechanical stop and prevent the sight from shifting. It will also help to prevent lens breakage as a result of over-tightening. Finally, when tightening rings, always tighten the bottom ring bolts first and then the top. This will also help to prevent lens breakage. The two ring halves do not need to be touching each other. If you farted, they are, you have almost certainly over-tightened your rings. Lens breakage is not covered by our warranty.

Oh no! In 30 years I have never broken a lens or distorted a tube! I use Pardini rings and they are not touching
Not to mention the extra 1/4 turn

From Weigand

Screw Size Screw         Torque Spec
 
6-32                            9 inch Pounds
 
6-40                            11 inch Pounds
 

6-40 (Flat Head)          11 inch Pounds

6-40 (Set Screw)          11 inch Pounds

6-48                            13 inch Pounds

8-32 (Flat Head)          18 inch Pounds

8-32 (Set Screw)           18 inch Pounds


8-36 (Flat Head)          20 inch Pounds

kc.crawford.7 wrote:From Weigand

Screw Size Screw         Torque Spec
 
6-32                            9 inch Pounds
 
6-40                            11 inch Pounds
 

6-40 (Flat Head)          11 inch Pounds

6-40 (Set Screw)          11 inch Pounds

6-48                            13 inch Pounds

8-32 (Flat Head)          18 inch Pounds

8-32 (Set Screw)           18 inch Pounds


8-36 (Flat Head)          20 inch Pounds

I have this on my tool box and I do have a nice Snap-On inch pound torque wrench!

Jim, you big fibber.

You only mentioned your calibrated flatulence to impress Wobbley!