Bending a barrel

[PathfinderNC]

I am curious about the affect of bending a barrel (this is an academy question for me as I don’t have a need to have it done).
From all I have read from some highly qualified people, the method if done right is very affective.
My question is this:
Won’t bending the barrel create a slight arc in the trajectory of the bullet as it travels down the curved bore? Or will it sail out straight from the direction it is going within the last few inches in the barrel?
Somehow I am imagining it will follow the gentle arc and hit its mark at a precise distance, say 50 yards. If the shooter aims at his target which is farther ( or nearer), how can the bullet hit the mark if it sighted in to another distance?
Probably a confusing question and not well articulated. I will try to draw a diagram of how I am envisioning my understanding of this.
Thanks

 

[LongWalker]

My question is this:
Won’t bending the barrel create a slight arc in the trajectory of the bullet as it travels down the curved bore? Or will it sail out straight from the direction it is going within the last few inches in the barrel?

This. The ball or shot exit square with the muzzle (assuming the muzzle crown is correct). Sights usually require some adjustment, but if there is no wind the projectile should travel in a straight line.

 

[PathfinderNC]

This. The ball or shot exit square with the muzzle (assuming the muzzle crown is correct). Sights usually require some adjustment, but if there is no wind the projectile should travel in a straight line.

Thanks. So the bend is not continued all the way to the muzzle, allowing for a proper distance of straight bore to create a straight trajectory. This makes sense to me now. Just trying to think through the process.

 

[user 31257]

I think it will fly straight as soon as the curved barrel ceases acting on it, but you could test your theory easily by blowing a ball through a piece of flexible pipe.

 

[LongWalker]

Thanks. So the bend is not continued all the way to the muzzle, allowing for a proper distance of straight bore to create a straight trajectory. This makes sense to me now. Just trying to think through the process.

Not exactly. The muzzle controls the direction of travel, the bend behind that moves the muzzle. The projectile can only exit square with the muzzle (assuming a muzzle square to the bore). QuinnTheEskimo has the right idea.

 

[smo]

I think barrels that need “bent” actually need straightened..

A Friend bent my Smoothbore barrel for me..
It took two tries too get it right, but now it shoots point of aim.. instead of 6” low & 1” too the left..

It’s more of a flex than a bend .. I would say.

Fixed my problem, but don’t know if a rifle with an octagon barrel would be as easy too straighten as my octagon to round smoothbore barrel was..

 

[dave951]

Once the projectile leaves the barrel, it travels in a straight line. Bending the barrel can alter the Point of Impact, but it also introduces internal stresses on the bullet that can lead to instability.

The Germans developed a rifle to shoot "around corners" in WW2, but the barrel had a very limited life and was very inaccurate.

 

[BillKilgore]

Bending a barrel could introduce a reduced diameter bore. I would suggest you proceed with caution. How much bend/flex do you think it needs?

 

[French Colonial]

This. The ball or shot exit square with the muzzle (assuming the muzzle crown is correct). Sights usually require some adjustment, but if there is no wind the projectile should travel in a straight line.

This is correct. I have bent one and helped regulate another.
Once sighted in for 25 yards you are still good at 50 yards for windage so the projectile is traveling in a straight line (Left to right)

This is with a smooth-bore, never tried it nor am I sure I would on a rifle gun.

 

[martin9]

I'm not sure how to post a quote but yep, whichever way the muzzle is pointing is the way the bulllet is going to travel...in a straight line....

I prefer to bend my barrels on new builds if they're shooting left or right. I don't want a front or rear sight that's not centered in the dovetail. Fowler barrels often need bending to shoot where I want. Octagon barrels bend just as easy as oct/rnd. I've noticed smaller caliber...say .32-.45 lighter barrels like A weights may need some bend correction more so than bigger diameter/bores barrels.

I agree that most likely a barrel that needs to bent needs to be straightened.

In my experience it has no negative effect on anything. All it does is make the gun shoot where I want. I think any ideas about negative side effects are just that....ideas....

Someone needs to come up with a new name for bending a barrel like "bullet path correction"....It's the word BEND that puts people off and has them imagining all kinds of bad stuff

 

[2 shots]

all has pretty much been covered above, but i think i bent mine too much, i can now shoot around corners....

 

[SciAggie]

Just to agree with others here - this is about Newton’s First Law. “Objects in motion stay in motion unless acted on by an outside force”. Once the bullet leaves the barrel it will continue in a straight line because of its inertia. The only forces that will alter the trajectory are the force due to gravity and any fluid friction due to air resistance.

 

[Brokennock]

I am curious about the affect of bending a barrel (this is an academy question for me as I don’t have a need to have it done).
From all I have read from some highly qualified people, the method if done right is very affective.
My question is this:
Won’t bending the barrel create a slight arc in the trajectory of the bullet as it travels down the curved bore? Or will it sail out straight from the direction it is going within the last few inches in the barrel?
Somehow I am imagining it will follow the gentle arc and hit its mark at a precise distance, say 50 yards. If the shooter aims at his target which is farther ( or nearer), how can the bullet hit the mark if it sighted in to another distance?
Probably a confusing question and not well articulated. I will try to draw a diagram of how I am envisioning my understanding of this.
Thanks

I bought a used .45 caliber "Kentucky Rifle," as my 1st muzzleloader. I was quite hyped to get it as I'd always wanted a long rifle, not liking half stocks or short barrels,,, and finding one I could afford.
I did not notice in my excitement that the barrel was bent to the right. When sighted in at 25 yards,,, shots at 50 yards were way off to the right... When adjusted to shoot poa at 50,,, it was way off at 25 and at 75,,,, there was no way to win here.
This does not happen with a straight barrel.
I imagine this tells us something about your question.

I have a few reasons that I don't like the idea of bending a barrel, the above is one of them.
However I think there is a big difference between bending a barrel to fix an elevation issue versus try to fix a windage issue. A barrel bent for elevation can be adjusted for using the sights. A barrel bent left to right or right to left is going to have the above problem.

 

[PathfinderNC]

I bought a used .45 caliber "Kentucky Rifle," as my 1st muzzleloader. I was quite hyped to get it as I'd always wanted a long rifle, not liking half stocks or short barrels,,, and finding one I could afford.
I did not notice in my excitement that the barrel was bent to the right. When sighted in at 25 yards,,, shots at 50 yards were way off to the right... When adjusted to shoot poa at 50,,, it was way off at 25 and at 75,,,, there was no way to win here.
This does not happen with a straight barrel.
I imagine this tells us something about your question.

I have a few reasons that I don't like the idea of bending a barrel, the above is one of them.
However I think there is a big difference between bending a barrel to fix an elevation issue versus try to fix a windage issue. A barrel bent for elevation can be adjusted for using the sights. A barrel bent left to right or right to left is going to have the above problem.

This was exactly what I was wondering. As I conceptualized it, if the barrel is bent a bit and sighted in at one distance won’t it be off at a different distance? But if there is a straight length from the muzzle back (how far I don’t know…) the bullet will travel straight. But won’t the point of aim/ point of impact change at variable distances if the front and rear sights are fixed at both ends outside of the bent section? Ugh… I’m lost

 

[Brokennock]

This was exactly what I was wondering. As I conceptualized it, if the barrel is bent a bit and sighted in at one distance won’t it be off at a different distance? But if there is a straight length from the muzzle back (how far I don’t know…) the bullet will travel straight. But won’t the point of aim/ point of impact change at variable distances if the front and rear sights are fixed at both ends ? Ugh… I’m lost

The bullet or ball is going to go where the muzzle is pointed. If it is pointed slightly to one side or the other of the breach face (just to pick some squared off point of reference behind the muzzle) the projectile will travel in that direction. Geometry being what it is, the further it travels, the further it will be from a straight line drawn 90° to the breachface downrange.

 

[2 shots]

straightened not bent

 

[Shadowalker164]

I would think bending as in gunsmithing would be to “ true” the bore.
I saw a myth busters where they bent a barrel. The round dissentagraded on fireing

 

[martin9]

Any gun that shoots progressively right or left as range increases has a bad crown. This is why shotgun patterns can be adjusted by filing a little at the muzzle.

Think of this in exaggerated terms....like shooting a spitball out of a crazy straw:>) The last couple inches is straight so the spitball will fly straight...the spitball does not know it went through bends and kinks

 

[LME]

This was exactly what I was wondering. As I conceptualized it, if the barrel is bent a bit and sighted in at one distance won’t it be off at a different distance? But if there is a straight length from the muzzle back (how far I don’t know…) the bullet will travel straight. But won’t the point of aim/ point of impact change at variable distances if the front and rear sights are fixed at both ends outside of the bent section? Ugh… I’m lost

A bent barrel will be accurate at only one distance a straightened barrel is a different matter? I think the latter is confused with the other. Some terminology confuses people , me included.I do know that shotguns , when looking down the barrel have a halo that indicates if the barrel is straight or bent. If bent a gunsmith will look down the barrel and ajust the barrel by bending it. I just can't see in my simple mind how any barrel that is bent, ie not straight, will shoot accurately? It defies physics?

 

[Brokennock]

Any gun that shoots progressively right or left as range increases has a bad crown. This is why shotgun patterns can be adjusted by filing a little at the muzzle.

Think of this in exaggerated terms....like shooting a spitball out of a crazy straw:>) The last couple inches is straight so the spitball will fly straight...the spitball does not know it went through bends and kinks

Not if the end the spitball comes out of isn't square to where it started.
Sure, it will go straight,,,,, straight in whatever direction the business end is pointed.