29 May 2009, 22:09
6.5GibbsProper stock screw tightening Weatherby Ultra-lightweight?
All of the sudden my 300 Weatherby Ultra-lightweight is spraying bullets all over the place. Same load as always (83 gr 7828 - 180 Barnes TSX) I took the stock off recently and put it back on tha same as always - reasonably snug on the screws, but not crazy tight. I'm guessing it's either the stock or possibly my Leupold Vari-X III 2.5x8 is loose inside. It sits in Leupold dual dovetail mounts that are loctited in place. What is the proper procedure for tightening the stock screws on this? The rifle is one of the earliest Ultra-lightweights and is about 10 years old.
Thanks in advance
29 May 2009, 23:40
onefunzr2Bobby Hart, my gunsmith, recommended 65 in pounds for the stock screws on my HS Precision synthetic stock on a 700 Rem BDL.
30 May 2009, 01:58
6.5GibbsMine were about 45 inch/lbs. I cranked them up to 65 - the front one first. I also swapped the scope for a Sightron SII 3x9. I actually think it's the scope, not the screws. I probably should have changed one thing at a time. Guess we'll find out in the next hour or so if it groups like it's supposed to.
Thanks for the info.
30 May 2009, 02:49
webfeetHS Precision stocks are supposed to be at 65 inch pounds of torque by design. The ones I have bought directly from them had that number in the instructions. Everything I have with a aluminum bedding block gets 65 inch pounds including my Bell and Carlson and Hogue stocks.
BTW: When I need 65 inch pounds I start with one screw and take it up about half way and then take the other screw to the same tension, and repeat the process snugging it up to get to 65. Just cranking one end to 65 and then doing the other can crack an aluminum floor plate or trigger guard.
30 May 2009, 05:11
Duane WiebeIt's not unheard of for any scope to "give up" I once worked for a large sporting goods firm and we had a fairly significant number of Leupolds that failed...then again, we sold hundreds!
We also sold Swarovski and Zeiss, Pentax..you name it! The failure rate was pretty low (percentage) in all of them..maybe Leupold among the lowest...but it does happen!
The lighter the rifle, the more of a beating the scope takes (inertia)
30 May 2009, 06:03
onefunzr2quote:
Originally posted by 6.5Gibbs:
...and put it back on tha same as always - reasonably snug on the screws , but not crazy tight. I'm guessing it's either the stock or...
One of those screwdriver torque gauges Midway sells certainly would set your mind at ease. Also less expensive than the Snap-on torque wrench in my toolbox. Or if it's a once-and-done deal, have your local gunsmith look it over.
I don't think the 300 W mag caliber has anything to do with how much those stock screws are torqued. It should go by the diameter and thread pitch.
30 May 2009, 06:38
JcchartboyJust an additional note...be sure to keep in mind every manufacturers stock has a different limitation. For example the McMillan on my Tar-hunt would literally be damaged by applying 65 in lbs (36 is max recommended), while as mentioned previously, that is just right for an H-S. Speaking with Mark Bansner he has found no accuracy difference between 35 and 70 in lbs with his Hi-Tech stocks and recommends 40 as very reasonable.
JC
30 May 2009, 12:39
webfeetAgreed...use the correct torque for your stock or bad things will happen. 65 inch pounds is way too much unless it was built for that specifically like the HS Precision or the others with bedding blocks I mentioned. A McMillan is not supposed to go anywhere near that high. I use 40 or 45 with pillar bedding, 30 or 35 with just epoxy bedding, and 25 with a wood or Tupperware stock.
08 November 2009, 10:18
6.5GibbsThis is an old post, but thought I'd update what I found in case someone down the road has the same problem and does a search. Turned out the Leupold's adjustment system went south. Leupold repaired it under warranty. I also asked them for the torque specs for base/ring screws with the torx head. They told me 20 inch lbs. for bases and 18 for the rings. Thanks to all who gave their .02!