How much force does it take to permanently bend a Cold Hammer Forged Barrel

[marathonrunner]

Guys, I have not been able to find any tests on this, I know AR15 barrels flex when shot. I have also seen when gunsmiths install flash hiders, the barrel flexes like a noodle but are there any youtube videos that show how much a barrel can flex before it passes it's yield point where it stays permanently bent?

I say this because I saw many FN PS90 owners making SBR's out of their 16" PS90 and it was amazing to see them applying a ton of pressure while drilling the blind pin out, then using a saw, the side force was yikes I would never subject my pencil thin barrel to that. Just carious

 

[Rastoff]

Too many variables to answer.

The yield force is dependent on many things. Bore to wall thickness ratio, type of steel, amount of bend. The short version is that a gun barrel can take a tremendous amount of force without deforming to the point where it won't work.

 

[marathonrunner]

Too many variables to answer.

The yield force is dependent on many things. Bore to wall thickness ratio, type of steel, amount of bend. The short version is that a gun barrel can take a tremendous amount of force without deforming to the point where it won't work.

OK to be more exact, a FN PS90. It has a pencil thin Cold Hammer Forged Barrel, but has a protective shroud over it which is only a cover. The PS90 barrel under it free floats inside, but is just a hair smaller in diameter(just enough wiggle room to hear a rattle if you shake it).

The reason I ask is I saw a youtube video of a shop drilling the blind pin in the front of the muzzle off and also using a circular mini saw to saw the end off while the receiver of the gun was locked down in a vice, thus 6" of the barrel was sticking out. The side force was pretty strong as you can see the guy really leaning into the drill. If the gun was a heavy barrel and it only costed $600 I wouldn't be that worried. But after paying $1400 Plus tax for what appears a bit cheaply made, along with a pencil thin barrel, just makes you wonder.

I have seen Windham factory tour video where one of the gunsmiths were torquing down a flash hider to the end of an AR15 barrel and you can see the whold barrel was flexing and moving like a noodle so I guess you are right, it can take a lot of flexing before it stays permenantly bent

 

[steelslaver]

One of steels great points is its ability to flex and recover to a degree far greater than most other materials. Steel doesn't permanently deform until it reaches what is called its elastic limit. Its elastic limit can be effected by, such things as cold forging, heat treatment, alloy etc. Amazingly tough stuff.

In the metal trades there is a tongue in cheek saying, "Don't force it, get a bigger hammer." But, generally on precision stuff it is better to go yo a better method before you end up resorting to another of steels great abilities. Being able to bend it back to where it was before or welding it back together.

 

[Rastoff]

Well, let me put it this way, a normal person is not strong enough to bend a rifle barrel, any rifle barrel, by putting only their own force on it. It would require some kind of mechanical advantage. Just pushing on it while drilling won't do it. Just pushing on it while cutting with a cut off saw won't do it.

 

[Arik]

$1400 Plus tax for what appears a bit cheaply made, along with a pencil thin barrel, just makes you wonder.

[emoji849]

You gotta stop looking at things in relation to your examples. It's a standard barrel and you can't compare it to a pencil regardless of it's thickness. Firearms can take A LOT of abuse... A LOT. They are stronger and more forgiving then you give them credit for. You can lean into it all you want it won't effect anything. Imagine the tremendous heat and energy that metal takes every time you fire off a round then add to that the fact that many of these are in select fire (military). If they were so weak they'd deform pretty quickly from the heat and energy generated.

Sent from my XT1650 using Tapatalk

 

[gregintenn]

You can bend one with a benchtop vice. Don't aske how I know.

 

[nachogrande]

EASY FIX.

Next time you are using that much brute force on a gun, Have someone SLAP YOU UPSIDE YOUR HEAD.

 

[Engineer1911]

It was a U-tube video. Don't worry about everything you see on the internet. How are you doing at reloading? Bent a gun barrel yet?

 

[drgbike]

4 FOOT PIPE ON END EQUALS RESISTANT FORCE

 

[marathonrunner]

There was a youtube video where a guy hung weights on the end of an AR15 barrel to see how much weight it would take to bend it past its yield point. I could not find it again but it was pretty interesting. Back in Granada conflict, US Army Rangers fast roping down a Helicopter did bend the barrel as it hit the ground. in fact several of them had bent barrels.

 

[Rule3]

I say this because I saw many FN PS90 owners making SBR's out of their 16" PS90 and it was amazing to see them applying a ton of pressure while drilling the blind pin out, then using a saw, the side force was yikes I would never subject my pencil thin barrel to that. Just carious

You have seen "many"?? Where?

If the barrel is bending, then they are not doing it correctly.

For $300 you can buy a 10" SBR barrel and save your regular barrel.
There are also reliable sources on the web on how to actually do it correctly. It is not just like sawing off a shotgun barrel

 

[Rule3]

And.......

Here is a truly Professional GunSmith performing the transformation.

Lets BUBBA a $1400.00 rifle!

[ame]https://www.youtube.com/watch?v=_CZScltLpnA[/ame]

 

[Engineer1911]

Total Quality: precision tools, clean shop, well lighted, expert craftsmanship, safety equipment, everything a well-trained professional gunsmith would use, do, or provide.

EDIT: The above is sarcasm directed at the idiot in the video!

 

[forestswin]

Well Superman bent a few in the original TV series with  his hand


And I think Bugs Bunny did too....but they were shotgun barrels.


I'm curious how Wiley Coyote paid for all the stuff he bought from Acme?

 

[johnt671]

A Marine in my squad bent the barrel of his M-16 by tripping and catching the rifle between two boulders. We were on a night patrol on Crete when it happened. Judging from the investigation by our butterbar you'd of thought he bent a jet fighter instead of a rifle.

 

[gregintenn]

Well Superman bent a few in the original TV series with his hand


And I think Bugs Bunny did too....but they were shotgun barrels.


I'm curious how Wiley Coyote paid for all the stuff he bought from Acme?

I always wondered why he didn't just order a bucket of fried chicken.

 

[marathonrunner]

Well it would be nice if somebody could make a video adding a dumbell weights in increments to see at what point it will not return to zero.

 

[LVSteve]

And.......

Here is a truly Professional GunSmith performing the transformation.

Lets BUBBA a $1400.00 rifle!

Cutting barrel off PS90 to finish p90 conversion - YouTube

I haven't looked at the video as I have just eaten. However, when i look at the still I can hear my father saying something about the proper tool for the job....for sure it's not in that picture.