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View Full Version : Torque Tuning a Savage Action, Does it really work?



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Texas10
11-21-2020, 01:46 PM
After reading this article posted to this site several years ago; https://www.accurateshooter.com/technical-articles/savage-action-screw-torque-tuning/ I've been performing this tuning technique on my and some fellow shooters rifles with good success. But I've never attempted to quantify the results of my efforts until recently.

The target below is a series of 10 rings with aiming dot. Shooting one round per ring and measuring the difference between point of aim (POA) and point of impact (POI). Wind flags were in use, winds were light and variable. Temps were mid 70's.

The chambering is 223Rem. The action is a stainless steel Savage model 12 small shank, two actions screws, J series purchased about 10 years go. It is installed in a Richards Microfit Benchrest thumbhole stock that is pillared and epoxy bedded by me. The barrel is a Criterion 8 twist, 26 inch that shoots remarkable well. The load is a 69 gn Lapua Scenar L over Varget with 205m primer.

I've labeled the rows and columns for clarity. Note target B1 is an annomility, and I both count it but also discount it in my figures for shot improvement after performing a torque tune.

The average error from point of aim to point of impact was reduced from .35 inch to .12 inch after adjusting the rear actions screw torque. If I throw out the B1 annomility the average for A1 thru A5 becomes .29 which reduces the degree of POI error slightly, but is still significant compared to the post adjustment targets.

The sample size of this test is admittedly small, but is at least some evidence of the value of this tuning procedure, and is offered as such.

As always, YMMV.

7576

Robinhood
11-21-2020, 05:56 PM
Thanks for putting in the effort Tex. I agree with your findings and I believe you will get people to see that once that action is seated to the point it is stable in the stock they will realize better precision. I saw it dramatically alter groups at mid and long range. Pillar and bedding improved things that much more.

It would be cool to see at least 3 shot groups at 300+. Easy for me to say huh? Another good post!

Texas10
11-21-2020, 06:57 PM
Thanks for asking, RH. This is a three shot group at 300 yds with my 6.5 CM. The dot is one inch, the group measures .19 moa. The load is a 140 SMK over H4350 and 210M primer in Hornaday brass. This load shoots very well both at 100 yds and 700, the furthest I've shot it so far.

The action is from a cheap model 12FV. The barrel a new 24 inch X-caliber, 8 twist. The stock is a factory Savage BVSS bedded and the scope a very inexpensive SWIFT 8-36x50 which does not have sufficient elevation for shooting 1000 yds even with a 20 moa base.

I shot my first for score match at 100 yds with this combo and scored 242 out of 250 and 6 X's. At distance it hammers all day long. One of the first things I did after initially developing the load was to torque tune the action screws, then proceed with fine tuning the load.

If you like, I can post pics of the targets shot in competition too.

7579

Smokey262
11-21-2020, 09:29 PM
Interesting. Just out of curiosity, how much torque do you apply to the screws?

Robinhood
11-21-2020, 10:01 PM
Not bad at all. Thats right in there with my 142 load at 400. I think the Lapua 139 scenar is a touch of an improvement in a Jim X-caliber.

Texas10
11-21-2020, 11:22 PM
Interesting. Just out of curiosity, how much torque do you apply to the screws?


It depends upon the stock material. In a stock (plastic) Savage stock I'll start with 45 in lbs on the front, and 10 or so on the rear, gradually working up in 5 in lbs increments while shooting two or three shot groups. On a more stout stock, 55 to 65 inch pounds to start on the front and 10 on the rear.

One thing I want to stress is to check the barrel rise as you tighten the rear screw. Do this by first setting the front screw torque, then place a finger in the gap between the barrel and forearm and then begin tightening the rear screw. If you feel the barrel rise as the rear screw is tightened, there's a bedding issue that much be corrected first.

Another issue comes to mind as I write this. When installing the barreled action into the stock, be careful to center the action into the stock before tightening the front screw by running a .005 shim around the rear tang and confirming clearance. It's easy to install the action slightly crooked so that one side of the rear tang is in firm contact with the stock. This will undermine any efforts to tune the action to the stock using the above procedure.

Texas10
11-21-2020, 11:32 PM
Not bad at all. Thats right in there with my 142 load at 400. I think the Lapua 139 scenar is a touch of an improvement in a Jim X-caliber.

In a previous 6.5 CM barrel I tried, the 142 SMK shot better groups at 1000 than the 140 SMK. Both were finely tuned loads, but the BC of the 142 is just that much better than the 140, and I was fortunate enough to arrive at the range just after they applied fresh paint to the steel. I've not tried the Scenar L in the 6.5, but since I don't have access to paper targets at anything beyond 300, I have no way to measure intrinsic accuracy of a particular bullet. The smallest steel target I have to shoot at 700 yds is 4 inches, and this load has no problem with that.

I imagine your load is a touch better, as are your rifles and skills. I'm still rather pedestrian in my skills and equipment, but i seem to get the job done.

Fuj'
11-22-2020, 09:03 AM
On my 3 screw target actions in my aluminum chassis, I set torque
at 50"lbs front. 45"lbs center, and 40"lbs rear. I then fire 5 rounds to
check impact but also to settle the screws. I check to see if torque
is still valid. I do this step because the front screw does not have a
lot of purchase. Back on target, I shoot for group and record. I then
tighten the rear screw 5" lbs. I generally find this tightens up the groups.
At this point, I recheck the other 2 screws, and call it a day.

shaffe48
11-22-2020, 09:22 AM
I tried different torques on the action screws for my accustock and didn't see a big difference. I could try on my other rifles. Both are glass bedded and one has pillars.

Fuj'
11-22-2020, 12:12 PM
I tried different torques on the action screws for my accustock and didn't see a big difference. I could try on my other rifles. Both are glass bedded and one has pillars.

A lot will figure in with how much weight is hung off the action.
I use heavy barrels where the muzzles are getting close to an
inch. If I was shooter a light sporter, I doubt my extra 5" lbs
on the rear would be valid. Also the material of the stock will
make a difference. A solid aluminum chassis which I use, probably
has more harmonics in the equation.

Been wanting to machine a chassis that uses a barrel block instead
of a "V" !! Hmmmnnnnn.....

Bill2905
11-22-2020, 03:30 PM
It depends upon the stock material. In a stock (plastic) Savage stock I'll start with 45 in lbs on the front, and 10 or so on the rear, gradually working up in 5 in lbs increments while shooting two or three shot groups. On a more stout stock, 55 to 65 inch pounds to start on the front and 10 on the rear.

One thing I want to stress is to check the barrel rise as you tighten the rear screw. Do this by first setting the front screw torque, then place a finger in the gap between the barrel and forearm and then begin tightening the rear screw. If you feel the barrel rise as the rear screw is tightened, there's a bedding issue that much be corrected first.

Another issue comes to mind as I write this. When installing the barreled action into the stock, be careful to center the action into the stock before tightening the front screw by running a .005 shim around the rear tang and confirming clearance. It's easy to install the action slightly crooked so that one side of the rear tang is in firm contact with the stock. This will undermine any efforts to tune the action to the stock using the above procedure.

Thanks for sharing this tip and your observations. Is the tuning improvement specific to a certain load that you like or do you find that it improves things across a variety of loads?

shaffe48
11-22-2020, 03:52 PM
A lot will figure in with how much weight is hung off the action.
I use heavy barrels where the muzzles are getting close to an
inch. If I was shooter a light sporter, I doubt my extra 5" lbs
on the rear would be valid. Also the material of the stock will
make a difference. A solid aluminum chassis which I use, probably
has more harmonics in the equation.

Been wanting to machine a chassis that uses a barrel block instead
of a "V" !! Hmmmnnnnn.....
The rifle in the accustock has a ' heavy barrel' my other two have sporter contours.

I've read it has a lot to do with how well the action is bedded with torque being more important with poorly bedded actions

Texas10
11-22-2020, 05:12 PM
75807581
More data points

Target on right, centered dot is starting with a loosened rear screw on a three screw target action. As you can see this 88 grain load is shooting over minute of angle. Top left is initial torque setting. Top right, more torque

Switching to left target, top row. First three shots are same torque. Next two with higher torque.

Below that are three shots each into three rows of a load development using 31.7, 32.0, 32.3 of Varget

Fotheringill
11-23-2020, 10:49 AM
All-

Verify with Savage recommended torque for factory bought rifle that you have. That would be a starting point. Each time you take the action out of the stock, the screws need to be torqued again. I would be concerned with the poster setting the rear at 10. That is really light. One also has to be careful in over torqueing lest something gets crushed a bit.

I have an Anschutz 22lr 54 action. Finding the best torque for front and back was a tedious and costly adventure.

Have fun.

lastedtiger
11-23-2020, 09:03 PM
The stock torque adjustment made a HUGE difference in my FCP-SR(Accustock) accuracy and the main reason i moved to aluminium chassis.
Texas10,
Try combining 140 SMK with Winchester 6.5 Staball and you may never load H4350 again:laser:.
Good shooting by the way.

Bama110Tac
11-28-2020, 05:50 AM
Some interesting points here. I have a factory 110 Tactical 6.5 in which I had the action out to lighten the trigger up a bit the other day and torqued it back down and I think the Savage manual says 45 in/lbs? Maybe 40, I can’t remember. I think it also says to have the rifle on its stock while pushing down on the action (the rifle would be pointed towards the air with the recoil pad on the table) while you tightened it.

I remember an article that Robinhood???? Posted about going in 10lb increments back and forth between the action screws? Until I can or do get a better stock of like to get the most accuracy out of the one I have and the best torque setting would be a start.

olddav
11-29-2020, 08:12 AM
No better way to determine the effectiveness of torque tuning of a Savage action than to try it yourself.

Texas10
11-30-2020, 12:42 PM
Some interesting points here. I have a factory 110 Tactical 6.5 in which I had the action out to lighten the trigger up a bit the other day and torqued it back down and I think the Savage manual says 45 in/lbs? Maybe 40, I can’t remember. I think it also says to have the rifle on its stock while pushing down on the action (the rifle would be pointed towards the air with the recoil pad on the table) while you tightened it.

I remember an article that Robinhood???? Posted about going in 10lb increments back and forth between the action screws? Until I can or do get a better stock of like to get the most accuracy out of the one I have and the best torque setting would be a start.

The article I linked in my post describes what you're asking about.

MT_Hunter
12-06-2020, 06:45 PM
Also the material of the stock will
make a difference. A solid aluminum chassis which I use, probably
has more harmonics in the equation.


Do you think this also applies to an aluminum bedding block like in a choate? Or what about a devcon bedded laminate stick. Very interesting concept. I'll have to look into testing this with my rifles.

What type of tool do you use to set torque on your action screws? Is it like a nut driver that you can set the torque? Or do you use a ratchet type torque wrench?

Thanks for posting about this.

MT_Hunter
12-06-2020, 07:17 PM
Apologies, should have read the article and looked at the pics first before asking about the torque wrench. Still interested in your thoughts about my other questions. Thanks.