Adjusting Bedding Torque
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Adjusting Bedding Torque
I originally tested my rifle with Lapua with a 10" tube mounted, as I was shooting prone-only at the time. However, since moving to shoot three-positions, I've largely abandoned the tube, and the other day, when I got another chance to test from a rig with Lapua, I confirmed my own fears that the ammunition that shot so well for me with the tube (12 and 13mm groups from the test rig) now shot very poorly, at 18 to 20+mm, all vertical stringing. Now, I've heard before that it's possible to use bedding torque to improve groups that string vertically like that, and was wondering where I should start. When originally tested, the torque setting was 6Nm in the rig, and I adopted the same setting in my stock. Is there any guideline that to improve I should go down, or up? It's an aluminium stock, by the way. I had thought of doing a forty shot match with settings from 4.5 to 5.5 in sequence, but am not sure whether that would be enough, or whether results from the shoulder might be misleading. I was shooting mid-580s but am now struggling to hit 580 at all with the ammo shooting as it does. Any thoughts?
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Martin Catley
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OK, a round action.
The round action can be a little sensitive to bedding, especially in the area of the front bedding screw.
The first thing to make sure of, if the vertical stringing is a bad as you imply, make sure the front bedding screw is not bottoming out as you take up the torque.
Next, if you don't have time for lots of testing most round actions are happiest between 40 and 45 in-lbs of torque. (4.5 and 5.1 N-m)
Now, Anschutz sells a rubbery mat to go between the stock and the action, they do recommend periodic replacement at some obnoxious price.
The Anschutz mat is fine as far as it goes but people report excellent results with other materials. While I have not tried it. (I am a disciple of Eric U and shoot a wood stock) folks have reported if you go to your auto parts store and get a sheet of the cork/rubber material people use for making their own gaskets and cut your bedding mat from that it seems to be the right combination of flexible but hard to get good bedding.
If you cruise the aisles at the hardware store, craft store and fabric store you can probably find several other candidates, then you can quit your job and take up bedding material testing... er bad plan... stick with the gasket material.
Anyhow cut the mat to support the action but do not support the tang (rearmost tongue sticking off the action), set the action screws for 45 in-lbs and you should be in pretty good shape.
I personally don't recommend torques any past 50 in-lbs (5.5 N-m) as the older Anschutz actions tended to have the threads pull out of the front of the action. That problem seemed to have been fixed by the time the 19xx came along but but I don't like tempting fate and accuracy wise I have never heard of anything past 50 in-lbs helping.
Hope this helps,
'Dude
The round action can be a little sensitive to bedding, especially in the area of the front bedding screw.
The first thing to make sure of, if the vertical stringing is a bad as you imply, make sure the front bedding screw is not bottoming out as you take up the torque.
Next, if you don't have time for lots of testing most round actions are happiest between 40 and 45 in-lbs of torque. (4.5 and 5.1 N-m)
Now, Anschutz sells a rubbery mat to go between the stock and the action, they do recommend periodic replacement at some obnoxious price.
The Anschutz mat is fine as far as it goes but people report excellent results with other materials. While I have not tried it. (I am a disciple of Eric U and shoot a wood stock) folks have reported if you go to your auto parts store and get a sheet of the cork/rubber material people use for making their own gaskets and cut your bedding mat from that it seems to be the right combination of flexible but hard to get good bedding.
If you cruise the aisles at the hardware store, craft store and fabric store you can probably find several other candidates, then you can quit your job and take up bedding material testing... er bad plan... stick with the gasket material.
Anyhow cut the mat to support the action but do not support the tang (rearmost tongue sticking off the action), set the action screws for 45 in-lbs and you should be in pretty good shape.
I personally don't recommend torques any past 50 in-lbs (5.5 N-m) as the older Anschutz actions tended to have the threads pull out of the front of the action. That problem seemed to have been fixed by the time the 19xx came along but but I don't like tempting fate and accuracy wise I have never heard of anything past 50 in-lbs helping.
Hope this helps,
'Dude
gtrisdale, the OP was getting away from the tube and shooting 3P with the standard length barrel. This is why the OP is focusing more on bedding torque.
The other aspect to this, sometimes you can have any old torque setting, put the tuner on and get really excellent performance. However, you are best served by having the bedding torque set for best performance without the tube prior to installing and adjusting the tube. If you work up from the most basic foundation you can get some really spectacular performance. If you put a tuner on as a band aid for bad bedding or poorly set bedding torque might be able to get decent performance but never great performance.
Dude
The other aspect to this, sometimes you can have any old torque setting, put the tuner on and get really excellent performance. However, you are best served by having the bedding torque set for best performance without the tube prior to installing and adjusting the tube. If you work up from the most basic foundation you can get some really spectacular performance. If you put a tuner on as a band aid for bad bedding or poorly set bedding torque might be able to get decent performance but never great performance.
Dude
torque
Throughout my years on the national team and through the Olympics.. I always set my rifle at the 5 nm setting. this is what the gunsmiths at Anschutz had set us up for as well. Anytime we had our ammo tested at the Olympic Training center for the year to match our guns.. our bedding torque was never a thought to change while testing our groups;. the ammo brand and the lot # is more of the focus. Not all barrels like the same brand. they all have their own personality. obviously. You also need to test it clean and dirty.
If you are going to shoot 3p outside.. I would say you would want a small tube. If your staying indoors the wind isn't going to be a factor and less of a problem.
Are you shooting the same brand as well as the same lot #? You need to test it out of a vise to see the full results as well to ease your concerns. I will be happy to help you with a suggestion if you email me with the problem if it persists. I know it can be frustrating. :)
Best Wishes. Jayme Dickman Shipley
If you are going to shoot 3p outside.. I would say you would want a small tube. If your staying indoors the wind isn't going to be a factor and less of a problem.
Are you shooting the same brand as well as the same lot #? You need to test it out of a vise to see the full results as well to ease your concerns. I will be happy to help you with a suggestion if you email me with the problem if it persists. I know it can be frustrating. :)
Best Wishes. Jayme Dickman Shipley