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Old 04-18-2017, 01:42 AM
Grumpygit

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Torque for action screws.



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I've recently acquired a Walther single shot target rifle. I'm not quite sure of the model, but it has a 100th anniversary thumb-hole stock with adjustable cheek-piece and butt pad.

At some point in its history, it has had the action bedded although it doesn't appear to have been pillar-bedded as well. Can anyone suggest an appropriate torque for the action screws?

I found a message from 2012 that suggested 15-25 lb.in. I would imagine that a bedded action should be at the top of that range and perhaps higher. Any comments?

Many thanks,

GG
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Old 04-20-2017, 11:41 AM
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If the action had been pillar-bedded, I'd suggest that action-screw torque is pretty much irrelevant, but glass-bedded without pillars renders the stock pretty much like one that is not glass-bedded, since weather changes can work to swell or shrink the wood (and the action is not resting on metal pillars). This means that torque becomes important. A suggestion that we see on the Anschutz forum a lot is to start at some torque value--say 20 in.-lbs.--shoot some groups, and then work up from there, for example from 20 up to 35 or 40 in.-lbs. until you find the torque setting that seems to provide the best groups. I wouldn't go any higher than 40 in.-lbs. for fear of crushing the wood. Once you know the optimal torque setting, you can make sure that each time you head to the range, you have adjusted the screws to that setting. If the wood has shrunk some, you'll have to tighten the screws to reach the optimal torque setting. If the wood has swollen, you'll back off a little.
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Old 04-20-2017, 02:02 PM
Grumpygit

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Thanks. I'm not certain that I'm a good enough marksman for my groups to show up differences in torques, but I'll give it a try. Presumably 50 yards should be far enough?
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Old 04-20-2017, 02:47 PM
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Quote:
Originally Posted by Grumpygit View Post
Thanks. I'm not certain that I'm a good enough marksman for my groups to show up differences in torques, but I'll give it a try. Presumably 50 yards should be far enough?
Yes, I'd say 50 yards is the ideal distance to do this kind of comparative testing. I guess first you'd have to try to find the ammo that the rifle shoots best. This can take some time and effort, and you'll have to decide on the quality of ammo you're willing to pay for. The high-end target (sub-sonic) stuff--like Eley Tenex, Lapua Midas+, and RWS R50 will generally shoot better than the mid-price target lines like Lapua Center-X, SK Rifle Match and Standard Plus, and Wolf Match Target and Match Extra.

Once you've settled on the ammo you want to shoot, you could start the torque testing at, say, 20 in.-lbs. and go up in 5 in.-lb. increments--25, 30, 35, 40. You'd need to shoot at least 5 consecutive 5-shot groups and take the average group size for each torque setting to have stable results.

If this all sounds like too much work (), I will say that many of the guys on the Anschutz subforum seem to have settled on a torque setting with their rifles in the 22-25 in.-lb. range. Walthers are very much like Anschutzes, so this might apply to your rifle as well.

I might add--for what little it's worth--that, with my Walther KK-MS, I have set the torque to 25 in.-lbs., and it has shot pretty well. However, I haven't conducted the test I've described above with it.

Your Walther sounds like a lovely rifle. Best of luck!

Last edited by South_Pender; 04-20-2017 at 02:51 PM.
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Old 04-20-2017, 03:31 PM
Grumpygit

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SP, thanks for the detailed follow-up. My marksmanship isn't good enough to warrant high-end ammo, although I'm hoping that this Walther might encourage me to move up a little higher. At present, RWS Target Rifle is about as exotic as I get, while I like SK Magazine for everyday use.

I hope to use it for 50m off-hand scoped rifle, so fancy ammo will be wasted on me for that kind of competition. I might also use it as an informal bench rest rifle at 100 yards if it behaves itself, so consistent ammo may become necessary.

I've recently built a one-piece stock and a custom rest for my Martini specifically for bench rest, but then this Walther came along (sigh). I'll modify the rest and then get started on the testing.

The Walther is stripped for cleaning and a check-up at the moment, but I'll post a pic when it's back together.

Thanks again,

GG
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Old 04-21-2017, 06:57 PM
andmars

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I asked Walther directly while querying the build date of my KKJ and they advised 5-6nm which translates to 44.2-53.1 in\lbs. I've always torqued mine to 45.

I also found my rifle loves the regular SK Standard Plus. Shoots all the Eley stuff terrible, RWS is ok, but the SK stuff is noticeably better.
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Old 04-21-2017, 08:34 PM
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Quote:
Originally Posted by andmars View Post
I asked Walther directly while querying the build date of my KKJ and they advised 5-6nm which translates to 44.2-53.1 in\lbs. I've always torqued mine to 45.
Yes, Anschutz has in the past recommended 5 Nm., or 44.25 in-lbs., and this has been discussed at some length on the RFC Anschutz subforum. The general consensus among many knowledgeable Anschutz shooters is that this is too much torque, leading to the possibility of crushing the wood. 6 Nm., or 53.1 in-lbs. is definitely too much torque and I'd strongly advise against it.

More recently, Anschutz has revised their action-screw torque recommendations, and now are suggesting that torques between 2.5 Nm. (22 in.-lbs.) and 4 Nm. (35 in.-lbs.) be considered and experimented with. You'll see the Anschutz torque recommendations in the following page of technical questions from the ANA website. Scroll down to the bottom of the page:

http://www.anschutznorthamerica.com/...questions.html

Anschutz warns that damage may occur by going over the upper bound of the range. So, I'd stop at 35 in-lbs., I think, and certainly wouldn't go over 40. Given the similarities between the Walther KK rifles and the Anschutz 54-actioned rifles, I believe that the Anschutz recommendations can be seen as applying well with Walther.
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Old 04-22-2017, 01:40 PM
andmars

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Keep in mind the KKJ stock has steel pillars inside it so you are torquing against the metal pillar sleeves and not the wood itself.
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Old 04-22-2017, 05:52 PM
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Quote:
Originally Posted by andmars View Post
Keep in mind the KKJ stock has steel pillars inside it so you are torquing against the metal pillar sleeves and not the wood itself.
That's interesting, andmars. My KKMS does have a sort of pillar attached to the bottom of the receiver at the front into which the action screw threads (see picture on the left below). However, this pillar doesn't extend all the way to the bottom of the stock, so that the front action screw is tightening up against wood on both the top and bottom. True also for the action screw at the tang. There are a couple of hard rubber or plastic inserts in the stock, but they don't really function as pillars, as they don't extend the full depth of the stock. As a result, I've been careful not to over-tighten.

The picture on the right below is of a KKJ. Again, tightening the action screws is inducing pressure against wood on both the top and bottom.


Last edited by South_Pender; 04-22-2017 at 06:03 PM.
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Old 04-22-2017, 07:36 PM
andmars

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Interesting, looks like the KKM is slightly different. On the KKJ they definitely do contact at either end.
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