February 24th, 2013

Innovative Borka Torque Setting Driver Belongs in Your Toolkit

Borka Torque DriverPh.D Engineer Boris Teper has invented a remarkably compact yet effective torque-setting tool that is ideal for tensioning scope ring fasteners and action screws on rifles. The Torque Settings Driver from Borka Tools is brilliant in its simplicity. The lightweight tool is basically a lever, with a series of hex slots through which a spindle is fitted. The slot position sets the effective lever arm length. How does the tool prevent over-torquing? That’s the magic of Teper’s invention. On one end of the tool is a handle with a spring-loaded ball detent. Once desired torque is reached, the handle overrides the detent, snapping forward so you can’t crank too hard (figure 2 below).

Borka Torque Driver

Borka Torque Driver

The Borka Driver is very easy to use, and despite its simplicity, it is very precise. Lab testing of the Borka driver show that the tool yields the correct torque setting within 4-6% of the true nominal torque measured with a calibration device. That means, for example, if you set the driver for 40 inch-lbs. it will torque the fastener within ± 2.5 lbs of your target setting. That’s as good as some full-size torque wrenches — pretty impressive for a tool that weighs only 4 ounces complete with spindle. And every Borka driver is calibrated to ensure accuracy before it ships.

Borka DriverBorka offers many versions of its tool, with torque ranges from 10 inch-lbs. up to 72 inch-pounds. The basic Borka driver, priced at $55.00, offers six (6) preset torque values. For $15.00 more Borka sells a driver that offers twelve (12) preset torque values. This 12-setting tool, which is not any bigger or heavier than the 6-setting model, is cleverly designed — you simply flip it over to switch from the first six torque settings to the second six. This works because the handle has variable “break” resistance depending on direction of travel. Smart.

Borka’s most popular torque tool is the 12-setting $75.00 “Military Grade” MG driver, model ATD-15×72-12FS-MG. This offers a dozen torque settings from 15- to 72-inch-pounds. We recommend the “Military Grade” model because it has torque settings laser-etched on the surface of the driver arm (see video). That way you’ll always know your torque values. The “Military Grade” model also comes with 1/4″ hex to 1/4″ square (M) and 1/4″ square (F) to 3/8″ square (M) adapters. The Military Grade Model, intended for use in the field by both DOD and LE personel, has already proved popular with “civilian” tactical shooters. You can store the tool in the supplied fabric carry pouch, or stash it (with needed bits) in your range kit.

Video Shows How to Use Borka Driver When Mounting Scope
We suspect many readers are still a bit confused as to how the Borka driver actually works. We could explain in greater detail but a video is worth a thousand words. In the YouTube video below, Frank Galli (aka “LowLight”) from Snipers’ Hide explains how to use the Borka torque driver. Frank demonstrates the $75.00 “Military Grade” Model, but all the Borka lever arm drivers share the same basic operation. Frank shows how to set the spindle position to your desired torque setting and hold to hold the unit properly. Watch carefully and you’ll see how the cylindrical handle at the end of the tool snaps forward or “breaks” when the desired torque setting is reached. Frank notes that: “there is no backlash when torquing. This is an excellent feature as it breaks clean at the desired weight.”

YouTube Preview Image

Where can you get a Borka torque setting driver? All models can be purchased directly from Borka Enterprises by emailing info@borkatools.com. You can also purchase through Manson Precision Reamers, (810) 953-0732. (Dave Manson worked with Boris Teper to get this product to market.) In addition, four models are available from Brownells: ATD-20X4006FS (Brownells item #080-000-734), ATD25X5006FS (Brownells item #080-000-735), ATD-36X7206FS (Brownells item #080-000-736), and ATD-15X7212FS (Brownells item #080-000-737).

DOWNLOAD: Intro to Torque Setting Driver | Borka Torque Driver Users’ Manual | Tool Calibration

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December 9th, 2012

Tuning Savage Actions Using Action Screw Torque Settings

This article originally appeared in the SAVAGE ACCURACY Blog

Stan Pate is the Captain of Savage’s National Championship F-TR Team. In this article, Stan explains how to adjust the action-screw tension on a three-screw Savage target action to achieve the best accuracy. The procedure described here can be used for any Savage action, including the two-action-screw models. However, the optimal settings for each particular rifle may vary slightly.

Match shooters need to get that extra accuracy edge from our ammunition and firearm. It is easy to get one of the Savage rifles to shoot accurately — even to match standards. If you are looking for that little bit more from your rifle, then please read a method that I have found that works for me. For those of you that are familiar with tuning a receiver (such as a match rimfire action), this article will be nothing new. For the rest of you, this might be new material. The goal here is to find the “sweet spot” for the rifle in relation to the torque settings used on the receiver screws. The proper torque settings [can vary] from rifle to rifle, but they will usually have a noticeable effect on consistent group sizes. A properly-torqued rifle will optimize the “harmonics” of the barreled action using the receiver screws so that the gun delivers peak consistency.

Here is the process I have found that works for me in tuning a Savage rifle receiver to peak accuracy. To use my process you first must already have a load that shoots accurately and consistently in your rifle, and I always use a fouled barrel like I’d be shooting in a match. This process works for me in both the model 10 (two receiver screws), and the model 12 (three receiver screws).

Seat Recoil Lug and Start with Front Action Screw(s)
On the model 12, I will first ensure that the recoil lug is seated securely against the stock by just lightly tightening up the front receiver screw then gently but firmly bumping the butt pad against the floor. Next I will tighten up the front two receiver screws to 30 inch-pounds starting at 20 inch-pounds and working up to the 30 inch-pounds in 5 inch-pound increments, and always tightening the front screw first and then the second screw. Once the front two receiver screws are torqued to the final torque setting, I will set the rear receiver screw to 5 inch-pounds and shoot a 5-shot group [to evaluate accuracy].

Increase Torque Incrementally on Rear Action Screw
After the group is shot and I am satisfied that I called all of the shots as good shots I will allow the rifle to cool off to about the temperature that the fist group was shot at. I will then add 5 inch-pounds to the rear receiver screw and shoot another five-shot group and allow the rifle to cool again. I repeat this process until I have tightened the rear receiver screw to 40 inch-pounds or have seen the groups get smaller and then start getting larger again. Once you have seen the groups decrease and then start to increase in size then you will have found the area of torque to work in. You can then can fine tune this to the exact inch-pound torque settings.

Tuning a Model 10 with Two Receiver Screws
The Savage model 10 action, which has two receiver screws, uses the same process as the three-screw model 12. Measure your group sizes and place the measurements in front of you so that you can see the bell curve showing where your best groups were achieved. NOTE — there may be a better way of doing this and if you should have one, I’d be very interested in hearing it. Good shooting and I hope to see you all on the range. – Stan Pate

This is on the Palma rifle using the torque settings of 30 inch pounds on the front two reciever screws, and 15 inch pounds on the tang screw, it is approximately 1/2″ center to center.
This is my second torque setting which for this rifle and this load is the optimal setting of 30 inch pounds on the front two reciever screws and 25 inch pounds on the tang screw, this group is approximately .180″ center to center.
This is the third torque setting which for this rifle is moving away from the optimal torque setting towards the heavy side of the scale. This torque setting results shows that you will usually see a “bell curve” of accuracy as you move into the optimal torque setting. This group is almost .7″ and the torque setting was 40 inch pounds.

This article was edited for length to appear in the Daily Bulletin.

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