Cojitatin' about "Torque'...

Dmay

Dmay

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Super GunNutz
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Of course torque, the force returned to the rifle by the force of the projectile being spun through the rifling, is a real force and a guy ( not me) could mathematic it into physical values. But I'm more thinkin' just practical "feel" and its effect on shooting, if any.

To whit: I'm building (another) stock-extension-plate-thingee to bolt on the bottom of my AR50 stock, 5" wide and extended about 8" in front for the obvious reason of shifting weight rearward. I'm debating off-centering it under the stock to account a bit for torque. However, while the force has to exist, I've never felt it. At least on this rifle.

Interjection: to inform that I shoot a long (31") barreled 7WSM (unbraked) rifle with which, especially when using a narrow-stance bipod, I can definitely feel the torque.

Anyway, I'm rolling this around in my mind and feeling that the effect of a very efficient (in this case stock Armalite) brake DOES negate some of the effect...at least "felt" effect. So just deciding to off-set it or not, realizing I may be doing nothing physically. However I also admittedly know that the psychological or OCD effect for a crappy shooter like myself can also be a factor, if not a "real" one.....
 
I think a fast twist barrel will torque more. Theoretically, anyways. 50 BMG is normally 1:15 twist and I'm guessing your 7mm WSM is somewhere around 1:8 twist if you have an aftermarket barrel on it.
 
Since you are curious about it, I would suggest looking into left hand gain twist barrels. They have some unique positive attributes, especially for right hand shooters.
 
The torque is applied to the barrel only while the bullet travels in
When it gets out, the barrel twist back to its original position. Its one of the forces that cause barrel vibrations which you want to get consistant when you handload. It is also one good part why how you hold your rifle will have some effect on poi at long range. The heavier the bullet, the faster the twist and longer barrel, the more torque you will get. Its pure and simple physics, but its way to far behind for me to remember how to calculate
 
I have played with torque issues on rifles for sometime.Actually had a physicist do up a mathematical formulae for
obtaining numerical values of torque on rifles.(Way too complicated)
Observed data through testing as you indicated will show target results and proof what works FOR you.
I have used Offset forearms for years on certain rifles to varying degrees of success.
A slow motion capture of your testing will provide substantial information in your testing.
Goog luck...Experimenting is half the fun.
Regards
Gord
 
From second year engineering school:

Torque = Polar Moment of Inertia x Angular Acceleration

If you are really interested pick up an old engineering handbook at a used book store and go at it. You can apply the same formula to the reaction of the rifle..
 
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