barrel torque direction

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Kenny Wasserburger
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Location: Gillette, Wyoming

Re: barrel torque direction

Post by Kenny Wasserburger »

Actually I understand what you guys are saying Newton’s law and all.

I have had a bruised cheek bone enough to realize is torques to the left. No mater what a firm grip is necessary.


Kenny
We'll raise up our Glasses against Evil Forces, Singing, Whiskey for my men, Beer for my horses.

Wyoming Territory Sharps Shooter
mdeland
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Re: barrel torque direction

Post by mdeland »

That was my first instinct as well but then I got to thinking about the friction of the bullet pulling on the bore interior as it turns right to follow the pitch. The barrel being much heavier than the bullet and the resistance to drive it through is so great that it would offset the bullet mass inertia with friction. I also got to thinking on how Pope purposely was said to make a left hand pitch to push the torque into his cheek . I think he shot right handed but could be wrong about that. The bullet is going to want to go straight ahead and the barrel is going to want to unwind from it so to speak so that would make the torque want to go counter to rifling pitch direction but the immense friction load would seem to want to drag it in the same direction as the pitch.
I'm wondering if and engine torque is a different set of forces/counter forces in operation with pistons involved in the crank direction inertia and no immense counter direction friction load on the cranks orbit perimeter.
When I got to thinking on it I've actually not been able to tell which direction the torque is on any of my heavy bullet 45-70 rifles. I would think the rifles with lots of drop would be the best indicators.
mdeland
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Re: barrel torque direction

Post by mdeland »

I test fire every barrel I install held vertical in both hands with the muzzle down into a lined throat steel sand trap and have not noticed any torque upon firing. I did a 340 Weatherby a few weeks ago that put so much burned powder gas into the trap that it lifted the lid and still did not notice any torque.
I'm thinking bruised cheeks may be more a product of cheek piece , stock drop and shape in regards to recoil than torque slap being the cause.
Kenny Wasserburger
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Location: Gillette, Wyoming

Re: barrel torque direction

Post by Kenny Wasserburger »

This May muddy the water a bit.


Not so with the effects of torque generated by a heavy bullet slamming along the rifling.
Most of us will notice that.
Frictional force against the bullet is in one direction, and the reaction of the rifling generating that resistance is in the other direction.
Right hand rifling twist generates torque to the right.

Frictional resistance forces in the bore have the opposite direction to bullet spin, all along the rifling, which makes the rifle react in the same direction as the bullet is spinning.

Looking down the bore from breech to muzzle: Right hand twist is clockwise. Bullet will spin clockwise, to right.

If bullet spins to right, rifling resistance is a force to the left (vectors left and breechward in direction of rifling lands and grooves). Rifle reaction to the in-bore torque force is equal and opposite.
The rifle barrel, which is attached to the rifling, will torque to the right.
In fact, the rearward component of that friction vector will also generate an equal and opposite reaction of the rifle, away from the shooter, reducing rearward recoil impulse.
But after the bullet is fully engraved, the magnitude of the rearward friction vector is small compared to the leftward frictional force vector,
at play until the barrel exits the barrel.
Minimal rearward recoil impulse reduction by increased twist rate is thus obtained. animal

Another way of looking at it is to say that the bullet slams into the rifling and pushes the rifling to the right, and the whole barrel follows that.
The barrel spins around its long axis,
and so does the rest of the rifle, if it is well attached to the rifle.

We perceive that as a twisting or torquing of the rifle in hand, away from the face of a right-handed shooter.
Into the face of a leftie.

Kenny
We'll raise up our Glasses against Evil Forces, Singing, Whiskey for my men, Beer for my horses.

Wyoming Territory Sharps Shooter
Gamerancher
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Location: Central NSW Australia

Re: barrel torque direction

Post by Gamerancher »

Yep, if I don't get a good hold on my .45-90 it'll jump out of my hand to the right, usually happens when I forget I've already set the trigger.... :oops:
Out in western NSW where it don't rain much.
Australia
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alfajim
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Re: barrel torque direction

Post by alfajim »

Looking down the barrel of my trapdoor from muzzle end the twist is counter clockwise, clock wise from the chamber end thus RH rotation rotation is applied from receiver end. Aircraft engine is also specified from rear cockpit end propeller opposite.The P-51 boys had a bad time with this as the torque reaction was so sever if they opened the throttle to fast it would roll the plane upside down hard on the driver.
On the car the upward lift from pushing down the gas if the torque reaction in the rear end the pinion climbing around the ring gear lifting the front end the torque is multiplied by the gear ratio. :shock: :roll:

Jim O
mdeland
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Re: barrel torque direction

Post by mdeland »

I think the torque load from the bullet inertia straight ahead and the barrel wanting to unwind from it is counter clock but the bullet friction load in the bore over powers it and the felt result is torque to the right or clock wise.
I read some where that is the reason Pope rifled his personal barrels with a left hand pitch to force torque into his cheek.
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kenny sd
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Location: florida

Re: barrel torque direction

Post by kenny sd »

OK. I notice that the groups get to be around an inch and round at 100 yds if I hold very tight on the stock. Pull tight into the shoulder.
74 Shiloh sharps 40 70 SS, 65 swiss 1 1/2 , 395 gg.

If I hold loose, the groups open up to 4 inches or more. so a tight hole MAY alleviate any torque. ?????

Ken
Coltsmoke
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Re: barrel torque direction

Post by Coltsmoke »

OK, now that we are using our minds eye to look at this torque in question, consider this, the bullet is spinning to the right, clockwise. The bullet is always pushing on the left side of the lands, which pushes the barrel to the right.
Normal isn't coming back, but Jesus is.
jackrabbit
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Location: Carpenter Wyoming

Re: barrel torque direction

Post by jackrabbit »

No, the bullet is going down the barrel, and trying to take it with it, thus torqueing the barrel in the same direction as the bullet is spinning.
bohemianway
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Re: barrel torque direction

Post by bohemianway »

Please stop. This is painful. Simple physics: bullet has gained momentum in the clockwise direction, Therefore the barrel has to be equal and opposite reaction which is Counter clockwise.

Draw a picture and be sure to note that the cheek rest is below the centerline of the bore. The movement of the stock is complicated by the fact that the center of the moment of inertia is not along the axis of the bore due to the action and stock mass being significantly below the bore centerline.

Try this: If the gun where out in space and you pulled the trigger, You are saying both the gun and the bullet will spin clockwise.

A friend once told me of a conversation with his girlfriend while driving on the highway through the woods of Wisconsin:
Friend: "Can you imaging how difficult it was to travel through these woods two hundred years ago?"
Girlfriend: "Yah, but the trees where smaller back then."

YRMV,
Charles
jackrabbit
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Re: barrel torque direction

Post by jackrabbit »

bohemianway wrote: Fri Apr 16, 2021 8:16 am
Try this: If the gun where out in space and you pulled the trigger, You are saying both the gun and the bullet will spin clockwise.

YRMV,
Charles
Yup
semtav
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Re: barrel torque direction

Post by semtav »

I have no idea, but I sure hope you get it figured out within 5 pages this time !!!

http://www.shilohrifle.com/forums/viewtopic.php?t=23430
Vern
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Joined: Fri Dec 02, 2011 9:28 pm

Re: barrel torque direction

Post by Vern »

Recoil is the effect of Newtons law when firing a rifle.For every action there is an opposite reacti
jackrabbit
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Joined: Mon Jul 23, 2012 12:04 pm
Location: Carpenter Wyoming

Re: barrel torque direction

Post by jackrabbit »

Dangit!! Now you got me wondering, too. I'll have to do some experimenting...

Sure is fun to argue about, though
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