Flexing a barrel

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Brokennock

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It is so minimal of a bend you can hardly see it.
The gun was only 5 to 6 inches high at 50. It didn't take a while lot of flexing.
The gun I had the trouble with also had elevation issues. The previous owner had filed way too much from sight off.
I never noticed the bent barrel,,, just just effects of it. I finally figured it out when I put a new, larger front sight on the gun and it seemed twisted as I could see part of one flat side of the sight when lining up a sight picture. With the barrel out of the stock I asked my friend if the front sight was twisted. He held the barrel to his eye looking down the top flat and noticed the bend.

It also seemed to cause other problems, patches and cleaning jags were constantly getting stuck in that bore. I wish i could replace that barrel as the rest of gun is fine.
 

Brokennock

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Another concern/question.
If one bends a barrel to gain, say, elevation in this case, and over does it or finds a better load that shoots lower afterward, or for whatever reason needs to now bend it again to decrease elevation.......
If the 1st bend occurred in the outer 3rd (or wherever, outer third is just an example) of the barrel length,,,,, how do you know you are bending the same spot back the other way? This is mostly for the, "stick it in the fork of a tree and haul on it," crowd, but would be a concern in general. I can see other issues arising from having a barrel bent two different directions in 2 different places.
 

sawyer04

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I have seen a barrel trued after leaving the factory. It was packed with hot sand, plugged and placed in a pipe bender. I would be afraid of denting the barrel trying to true it dry. I suppose the sand method would work on an octagonal barrel.
 

Packrat

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I was at the old Springfield Armory many years ago, it had been closed since the late 60's, the guard took me through and in the back there was a wheeled machine, I say wheeled because it had a pinch mechanism with a wheel, a barrel was put in a jig and the operator, during the Civil war looked down the barrel at a candle / lantern mounted way down the the hall and turned the wheel to move / bend barrel to center the candle into the center of the barrel, when I was there 71 or 72 they had put a light up instead of the candle or lantern
 

Whisper

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I bought a TC Renegade from a guy on another site for $200. The rifle looked it was in great condition so I couldn’t understand why he was selling it so cheap. When I got it and took it to the range I found out why. It was shooting high by 12” at fifty yards. At first I started looking into replacing the sights. Then it dawned on me to put a straight edge on the barrel. Sure enough the barrel was bent and it looked like it came that way from the factory. So I got out my hydraulic press and a couple of 4x4s and straighten it out. It turned out to a very accurate gun.
 

Joemolf

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Everytime I bring up this practice it seems like people's heads want to explode.
I bent the barrel on my smoothbore upwards to get it shooting... Since then killed 2 doe. (I did this even after I filed my the front sight down it still shot low.)

I did it with my rifle after building it.
The gun shot too low and I didn't want to try to the file the front sight and potentially scuff my barrel which I worked so hard to get to the desired finish it had.

Barrels are soft, it usually doesn't take much to "bend" it and get it shooting to your desired POA.
On multiple occasions a barrel manufacturer and gun builders both told me they do this with their barrels if need be.
Obviously if sights can be altered some, you just as well do so.

I originally bent my rifle barrel because of original low impact and had it shooting high...I then realized over time it just shot too high for my liking. This week I took it in and out of the gun firing a few shots per alteration and flexing it in my vise till I got it shooting just perfect.

I will say I went too far the one time and could physically see the hump in the barrel. Scared the tar out of myself... But realized its nothing I can't undo.... I flexed it back and it straightened back to how it was originally, at least to the naked eye. It then shot high just like before I started. Then I was more gentle with the multiple pulls of the barrel in vice. Bingo....got it shooting perfect.

Have you ever done this?
Interesting I saw a guy on YouTube do this! I was like good grief then I went and look at the SMR I bought from a guy off the forum and thinking just thinking if I should try it Rifle shoot s a little left about 4 or 5 inches at 60 yards. But then I was looking at how well the barrel is snug to the stock. Obviously wouldn’t put a big bend in it and said forget it. So is the barrel of rifle that need to be tweaked in this fashion sub par? I can see this method being used on hand made but with today’s machines what does it say if anything about the barrel
 

Brokennock

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So is the barrel of rifle that need to be tweaked in this fashion sub par?
In my opinion, yes, yes it is sub-par. A well made barrel should be able to be regulated for p.o.a./p.o.i. using the sights. I'm sure others will disagree.
I think the usual reason for needing this degree of correction is "run out."
It is very difficult to bore a roughly 44 inch hole in something and not have it wander at least slightly.
I've read people saying that it is a good idea to check a barrel for run out before installing barrel lugs and sights. This way one can orient the barrel so that any run out is vertical because it is easier to correct for with the sights and if bending is needed it is up and down, which again is less problematic over distance than bending left to right.
 

gundoc2000

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I have straitened or sighted barrels on center fire and black powder guns for many years with just a pair of heavy leather gloves and an old stump of firewood to whack the barrel on works great and you can take to the target range to get it right the first try also works on non vent rib shotgun barrels

gundoc
 

M. De Land

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Run out at boring is the main issue and no bore is perfectly straight but if they can be kept to .003-.004 run out in 30 inches that is about as good as it gets from what I've read.
Deep hole boring is the real science of quality barrel making not the rifling. As the hole gets deeper the oil pressure to remove the swarf (chips) has to be increased to keep the borer on center and not deflected by chip bind. Barrel holes are not only off center on a straight tangent they are also bored off center on a serpentine (cork screw) in some cases. One can readily see this by mounting a barrel in the head stock of a lathe, dial indicating both bore ends then looking though the bore while the head stock is revolving at a slow RPM. It will often look like a jump rope down bore.
This is the reason any muzzle loading barrel should be orientated with run out in the vertical at 12 o'clock. This is particularly important in most muzzle loading barrels as they tend to be much longer than a typical HP rifle barrel.
I think barrel bending still has some application but mostly in shot gun use. I don't want it at all in my rifle barrels personally.
 

Red Bob

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In the late 70s I worked at Diesel engine manufacturing shop. I checked camshafts for trueness.
When I had a palette of them that were out of spec I would take them to jig with a hydraulic press and adjust them into spec.
 

M. De Land

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In the late 70s I worked at Diesel engine manufacturing shop. I checked camshafts for trueness.
When I had a palette of them that were out of spec I would take them to jig with a hydraulic press and adjust them into spec.
Well with a cam shaft, corrected journal alignment and new tight bears hold the shaft in supported alignment. A barrel has no such rigid support . It has only it's own bore straightness and stress relieved steel rigidness to keep things in line. A stress relieved ,straightly bored barrel will tend to hold it's shape even when it heats up were as a stressed (physically bent) barrel will tend to "walk" it's shot placement as the heat increases.
 

martin9

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Have you seen a barrel that was bent "walk" shots as it heats up?
 

Spence10

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A New Voyage to Carolina; Containing the Exact Description and Natural History of That Country: Together with the Present State Thereof. And A Journal of a Thousand Miles, Travel'd Thro' Several Nations of Indians. Giving a Particular Account of Their Customs, Manners, &c. by Lawson, John, Gent. Surveyor-General of North Carolina [printed 1709]

"Our Indian having this Day kill'd good Store of Provision with his Gun, he always shot with a single Ball, missing but two Shoots in above forty; they being curious Artists in managing a Gun, to make it carry either Ball, or Shot, true. When they have bought a Piece, and find it to shoot any Ways crooked, they take the Barrel out of the Stock, cutting a Notch in a Tree, wherein they set it straight, sometimes shooting away above 100 Loads of Ammunition, before they bring the Gun to shoot according to their Mind."

Spence
 

M. De Land

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Have you seen a barrel that was bent "walk" shots as it heats up?
I have seen brand new HP barrels I personally mounted walk after 3-4 shots on occasion and do it repeatedly. I would bet money they had been factory straightened in a barrel vice and were stressed. There is no other reason for them to react like that to heating up.
 

Brokennock

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Most hunting is a one shot deal so the walking isn't a big concern.
Working the muzzle or crown does not walk shots.
It does make me chuckle. Folk will consider bending a barrel but touch the crown! Burn him on the stake!
It's way too easy to square up the muzzle again if one goes too far,,,, much better to risk having a barrel with multiple bends to look swells at slack tide.
 

Britsmoothy

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It's way too easy to square up the muzzle again if one goes too far,,,, much better to risk having a barrel with multiple bends to look swells at slack tide.
It really is not difficult at all.
Most believe a crown or muzzle is akin to a sacred idol. And any tampering with will bring the plagues of a thousand demons upon thee!

Has no one clicked why original rifles had that relief filing around a crown yet?🙄
 

smo

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I’ve never seen a barrel on a rifle bent, but I’ve seen a couple I wanted too wrap around a tree….😡

A Friend of mine bent my smoothbore so it would shoot more too my point of aim,
It took removing the barrel a couple of times too get it right, but it wasn’t that hard.

My Friend is 6’2 and weighs around 220.
He had most of his weight pressing against the 44” barrel to flex it.

He used the fork of a tree and his body weight pushing against the barrel..

He said you can feel it when it moves…

I would think this would take quite a bit of force too move a octagon barrel…
A jig or something for a more controlled method of applying pressure would be a better method, I would think.

A smoothbore is more like flexing a piece of tubing.
The wood then conforms too the flex/bend.
The issue one needs too watch is when reinstalling the pins not too blow a piece of wood out of the back side when the pins are re installed…,


I’ve never tried filing the muzzle….,simply because I’ve never really understood the effects or exactly what needs too filed…

But I’m definitely not against giving it a try,,I’m just curious as too how much filing it would take to move the impact of a .648 ball 6” at 50 yards?
 

Britsmoothy

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I’ve never seen a barrel on a rifle bent, but I’ve seen a couple I wanted too wrap around a tree….😡

A Friend of mine bent my smoothbore so it would shoot more too my point of aim,
It took removing the barrel a couple of times too get it right, but it wasn’t that hard.

My Friend is 6’2 and weighs around 220.
He had most of his weight pressing against the 44” barrel to flex it.

He used the fork of a tree and his body weight pushing against the barrel..

He said you can feel it when it moves…

I would think this would take quite a bit of force too move a octagon barrel…
A jig or something for a more controlled method of applying pressure would be a better method, I would think.

A smoothbore is more like flexing a piece of tubing.
The wood then conforms too the flex/bend.
The issue one needs too watch is when reinstalling the pins not too blow a piece of wood out of the back side when the pins are re installed…,


I’ve never tried filing the muzzle….,simply because I’ve never really understood the effects or exactly what needs too filed…

But I’m definitely not against giving it a try,,I’m just curious as too how much filing it would take to move the impact of a .648 ball 6” at 50 yards?
Not much at all.
If say you want to move that ball up you would remove a cresent fron the muzzles lower half or if it is a thin walled muzzle file across from top to bottom or bottom to top but remove more material from the lower half.
Regarding how much. Very little, barley visible. Less visible than a bent barrel for sure!

Everyone thinks you need a lathe to finish a muzzle. You don't! They didn't! They being early barrel makers.
I've seen mass produced choke tubes throw shot off course.
I've cut 22lr barrels, air rifle barrels and finished the crown by eye, they shot fine and close to centered sights.
I've adjusted several shotguns but only ever bent two. One I bent in the field as I did not care for it and it was skirting the birds. In desperation I tore it down and jumped on it in the plough! Smoked the birds after. The second was a muzzleloader. Wished I hadn't. All I did was look at the bend. I should of worked the muzzle instead.
Back to amount, its a subtle an amount as it is discernable to spot the difference in that fancy looking filing they use to do on original barrels!
Think about it, how did they put them grooves on a muzzle at an angle and get every one the same?
Answer; they didn't! We are looking at a method of regulation to bring a hand cut barrel near to the centered sights.
 

Allenby

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Val Forgett , who was a prime mover for muzzleloading rifles ; strongly advocated bending barrels .
 
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