Polygonal Barrel Theory. Respomses welcome

[Carbon]

SOme where in the tech threads there was something about the ideal barrell to ball fit, it involves two points of contact of the ball and barrel (figure A). The theory is... would not a triagular barrell or a polygonal with multiple contact points be a more ideal paint to barrel match (Figure B & C)? Mind you these pictures are exagerrated.

Would it not be more gas eficient? I know HK and Glock uses polygonal barrells in order to produce higher bullet velocity as well as a tighter gas seal. Has anyone built barrels like this, i know Armson rifles AND TWISTS their rifling, i was wondering if a 8" to 10" Polygonal "controll back" with STRAIGHT rifling could provide more accurate shots. I suppose the "lands and Grooves" of these barrel would have to be done in thousand maybe hundreds.
Im no machinist, but i wonder the degree of difficulty and cost effectiveness in fabricating such a barrel. In anycase, yall techheads fell free to drop in anything i missed in regards.

[Miscue]

Won't help. The ball is inaccurate to begin with... rifling does nothing.

[darklord]

I see your point, but, as miscue pointed out, not all paintballs are the same size, even in the same bag.

[MarkM]

I understand what you are trying to say aswell, but even if you were to get "perfect" balls then your design would be super inefficient due to large amount of wasted air over the current barrel types on sale. Oh and straight rifling has been done by J&J many years ago...got a couple of those brass tubes lying around somewhere ;)

[Smokee_2_7]

someone please correct me if im wrong, but wasnt tom using perfect circle balls when he noted the 2 contact points inside the barrel? If so, I can definitly see where Carbon is comming from.


Micsue, Are you not thinking of 'rifiling' in the "traditiona" sense? With the channels and grooves cut in a spiral pattern to induce spin?

This theory would has nothing to due with 'spinning' the ball- - which we know not to work. IF increased contact area does increase gas efficiency, then I think there is somthing that could come from this design. I would like to see this threory tested, for sure.

Carl

[thevilduk]

1) the gas efficency would be terrible due to the open space for gas to flow around the ball

2)paintballs suck tons for projectiles

3)it would take many hours to machine a barrel out like that, the only real good way to do it is to e.d.m. it out, or i think you can use a broach.

[Miscue]

Originally posted by Smokee_2_7
someone please correct me if im wrong, but wasnt tom using perfect circle balls when he noted the 2 contact points inside the barrel? If so, I can definitly see where Carbon is comming from.


Micsue, Are you not thinking of 'rifiling' in the "traditiona" sense? With the channels and grooves cut in a spiral pattern to induce spin?

This theory would has nothing to due with 'spinning' the ball- - which we know not to work. IF increased contact area does increase gas efficiency, then I think there is somthing that could come from this design. I would like to see this threory tested, for sure.

Carl

Straight, Spiraled, Polygon... whatever... don't matter.

[P8ntballerAK]

wow, did you guys even read the post?

he said his pics were exaggerated, what he is talking about would nt make it less efficient but more efficient and it would make for better accuracy since the ball would be con more than 2 sides of the barrel. the gaps he posted are to big but again he said it was exaggerated, I will try to make a more realistic perspective. The sides where its touching would have more contact and the area where you see spaces would be really minute.

[Aliens-8-MyDad]

we should make barrels out of jello so it conforms to the balls curves and gives u a perfect shot no matter what shape the ball is :)

[joeyjoe367]

Originally posted by Aliens-8-MyDad
we should make barrels out of jello so it conforms to the balls curves and gives u a perfect shot no matter what shape the ball is :)

Just use a garden hose :)

[joeyjoe367]

Originally posted by P8ntballerAK
wow, did you guys even read the post?

he said his pics were exaggerated, what he is talking about would nt make it less efficient but more efficient and it would make for better accuracy since the ball would be con more than 2 sides of the barrel. the gaps he posted are to big but again he said it was exaggerated, I will try to make a more realistic perspective. The sides where its touching would have more contact and the area where you see spaces would be really minute.

Check out "Deep-Blue" and the "paintball spin physics" thread. What makes a paintball innaccurate is another force that has nothing to do with barrel geometry; it's aerodynamics of a sphere.

[cledford]

The point that Miscue is trying to make is that no matter how you make the barrels, once the ball enters the atmosphere IT becomes inaccurate due to it's nature. Nothing, short of changing the shape of the paintball to something other then a ball, will EVER affect the accuracy of one. This is due to what happens to the ball in flight based on the laws of nature that dictate what happens to air flowing around an inperfect sphere.

It can never be changed no matter what. Tom just made a big post about this after a discussion in deep blue. It is not the barrel or guns fault.

-Calvin

[cledford]

Oh, and Armson already makes a polygonal rifled barrel...

[Miscue]

Yep... and it doesn't work any better than the other fancy hollow tubes. :)

[P8ntballerAK]

here is a barrel with ten sides un rounded

[P8ntballerAK]

here is a barrel with 6 sides rounded

[P8ntballerAK]

I know what tom did and es armson makes the stealth barrel, but the point is its not LESS efficient. and i think that making a polygonal barrel does make a difference, just not a big enough one to notice with paintballs. There is a reason BB guns are rifled, and thats because it makes a slight difference on accuracy that can be seen because a bb is so small. Paintballs create quiet a bit of turbulence once in flight, thats why they are so inaccurate. even if paintballs were more bullet shaped, the difference in rifling still would not be enough to notice on the field.

again my point was merley on the efficiency of the barrels.

[Carbon]

Yes please read the whole thread before sayin something. But i get your point about the paintball being innacurate: it is an effect caused by atmospheric/aerodynamic turbulance.

But like all theories, Its a theory. It would be cool to actually see one of these polygonaly type barrell go side to side testing vs a DYE bomstick or some this just for *EDIT* Do not circumvent the cuss filters, this is NOT your average website, we actually enforce those rules you agreed to follow. Army and gigles. thnx for your commnets anyway.

[Miscue]

No theory.

AGD spent a ton of money researching this stuff with high speed cameras. They had really fast rotating barrel and stuff to make it spiral. What they found is that... the ball goes all over the place... wobbling... they are horribly inaccurate to being with. Same effect no matter what they did... even with Perfect Circle balls. I dunno if the info is still floating around on AO somewhere...

[mag-hatter]

oh man it hurts just thinking of how hard it would be to clean that thing!

[Carbon]

Miscue For gods sakes, im talking about straight rifling here, no spinning the balls, no spiral rifling, no spinning the barrel. I want to see a (insert brand name barrel here) VS A POLYGONAL STRAIGHT RIFLED BARREL. Marginal or not the results will show a "cluster pattern". I want to know what that pattern is.

Furthermore, I would like to see if the polygonal barrels are more efficient.

yes, Paintball shapes are inconsistent, but with a of box 2000, they are consistant enough to get a Mean or average size, shape ect.

Yes theories are theories. You can say i told ya so once actual testing is done. Thnx.

[Temo Vryce]

Originally posted by Miscue
No theory.

AGD spent a ton of money researching this stuff with high speed cameras. They had really fast rotating barrel and stuff to make it spiral. What they found is that... the ball goes all over the place... wobbling... they are horribly inaccurate to being with. Same effect no matter what they did... even with Perfect Circle balls. I dunno if the info is still floating around on AO somewhere...


AGD also stated that spinning the balls showed no improvement. He never said that rifling didn't work.

I believe that the thread you are refering too is in Deep Blue Miscue.


http://www.automags.org/resource/tech/tomstech/03_spinning.shtml
http://www.automags.org/forums/showthread.php?s=&threadid=64669

[bofh]

Originally posted by MarkM
Oh and straight rifling has been done by J&J many years ago...got a couple of those brass tubes lying around somewhere ;)

My too, got me a four land straight rifled J&J barrel, which is not anymore accurate than a non-landed one.

Not any worse effiecney wise either...

[hitech]

You cannot make a more accurate barrel. Vortex shedding is the root cause of paintball inaccuracy. 2Gs worth of lateral force. It is amazing they hit anywhere near where we are aiming. Here is the deep blue thread:

http://www.automags.org/forums/showthread.php?threadid=64669&goto=newpost


You may be able to make it more efficient. I've noticed that a tighter barrel is more efficient. The better seal seems to make up for the extra drag. However, it kills your consistancy. :(

[joeyjoe367]

Originally posted by hitech
You cannot make a more accurate barrel. Vortex shedding is the root cause of paintball inaccuracy. 2Gs worth of lateral force. It is amazing they hit anywhere near where we are aiming. Here is the deep blue thread:

http://www.automags.org/forums/showthread.php?threadid=64669&goto=newpost


...exactly what I was trying to say in my first post. Paintballs are innaccurate *OUTSIDE* of a barrel. The barrel is not the limiting factor in a paintball's accuracy.

[BarryTolar]

Glock and HK don't use polygonal barrells. Some models from each maker use polygonal rifling.

And even then it's not what most people think of when you say polygonal. Another manufactor also did something wil bizarre rifling patterns but I can't remember who right now.

Barry

[shartley]

Comparing paintballs with standard gun ammunition, and paintball markers to standard firearms, is where theories get tossed in the trash. And I will leave it at that.

And for the sake of argument, even if it DID work, it is much cheaper to make round barrels than barrels with special shapes. Would any accuracy gained be worth the expense? I would bet the answer would be no.

[Evil Bob]

The problem lies in fluid mechanics. Paintballs contain a non solid material that takes quite a bit of inertia to spin evenly with the outside shell, something that is not possible with the current barrel length and the speed at which we play at for safty reasons. This is why Tom tested with a high speed barrel spinning gizmo to get the paint core to match the speed and rotation angle of the outer shell.

You can easily test this concept out yourself, go visit any sports store that carries one of those dynamo wrist exercisers with the weighted spinning core and play with it, once you get the core spinning, you can feel how that mass impacts any movement you try to induce into it.

Firearm projectiles are solid, a solid projectile can be easily stabilized in flight by inducing spin at right angles to the flight path, this results in a flatter trajectory due to the physics involved (gyro stabilization).

If we were to use a solid projectile in paintball and crank the velocity up to a few thousand feet per second, then we would definitely see some benefit from spin stabilization, but we'd end up killing each other.

-Evil Bob

[joeyjoe367]

Originally posted by Evil Bob
a solid projectile in paintball and crank the velocity up to a few thousand feet per second, then we would definitely see some benefit from spin stabilization, but we'd end up killing each other.

-Evil Bob

Sounds good to me. Let's go for it :D

[tobz]

thing that I would like to add...

those two "contact points" are because the paintball itself is larger at the "equator" where the two shell halves are "put together" so creating more contact points will not effect it in any positive way, even with a perfect circle, since the extra drag + all of the wasted air around the ball would make it no longer worth it anyhow.

tobz

[FeelTheRT]

wow look how in efficent that thing would be. IMHO, it is all the paint you use. If you use very high quality round paint such as many RPS paint and fresh DraxX, your going to shoot accurately if you have a consistant marker and any aftermarket barrel.