Look Ma!! It's a Dimpled Paintball!!!

[AGD]

Well sort of, it's nylon and the right size and weight. The idea of dimpled paintballs comes up every couple months and we always have to tell them sorry we tried that and it didn't work.

Here is a pic I have been meaning to post. I thought I would share it with all of you before I move it to deep blue.

AGD

Bunny- Couldn't find picture - 5-28-2017

[Mossman]

Put em in the store...I'll take 3!

[pito189]

Ahhh it's cute like a baby golf ball. Can these balls be used for chrono testing and such?

[Jack & Coke]

I wonder how much that thing would curve if I shot it from my Tippy Flatline...

Damn thing would probably fly around and hit me in the forehead...

[Dslexik]

There was a lot of hype a couple years ago on how the dimples really help with flight trajectory and wind resistance. Companies were coming up with baseballs, footballs, etc, even bats that had dimples in them. They said it was going to revolutionize sports. Well guess what, you don't see em at all today do ya, except on golf balls.

[dio91]

Correct me if I'm wrong, but are those the same nylon "paintballs" used to chrono and test before shipped out to distributors and sold? The same ones in the video right?

dio

[yeahthatsme]

/me applaudes agd!!!!!

[HoppysMag]

so tom, what was wrong with them? fly funky?

[sniper1rfa]

i have a feeling i know why they didnt work well. dimples that large would be no different, or possibly worse, than a rough surface.

AGD, did you test these agains paintballs or other, smoother nylon balls?

[FalconGuy016]

I think dimples would be a great idea...??? Look what they did to golf balls, I think sniper is right. They are way to big (out of proportion to a golf ball dimples)

[Emagster]

not sure what it would do for paintball and it's flight in the air or anything. but the dimples actually do have advantages in golf and skiing(yes skiing). Not sure what they do in golf since i ahven't ever played and never pay attention to it. but skiing thats another thing. the ski's I have are dimpled like the surface of a golf ball to lower the friction and turbulance the ski aquired as it goes across the snow

[FalconGuy016]

I would expect it has a great effect on any round hard surfarce that flies through the air at high speed... like a paintball

[sniper1rfa]

actually, they ARE in proportion to golf balls, sorta. and thats the problem.

the problem is, on something this small, tiny impurities in the surface can do the same thing as dimples. in a fluid dynamics book a read, a 3 inch rough sphere had 5 times less drag at 125 mph winds than a smooth one. and the roughness was in the form of scores only .003" deep.

we want a lot of turbulance in the boundary layer on paintballs, and i think at this size and speed, dimples arent the way to get it. a rough surface woulde be better.



AGD, have you tried smooth against one roughened with, say, 100 grit sandpaper?

[deathstalker]

I thought dimples on golf balls were beneficial because of spin. I don't think paintballs spin so fast that dimples would make any difference whatsoever (as shown in the data thread). Wouldn't this be the same reason you don't see dimpled baseballs, footballs, etc.? It's not like I want my paintballs to land 10 ft. past my target and roll backwards to it.

[sniper1rfa]

nope, the point of dimples is to cause a turbulant boundary layer, thereby decreasing drag (funny, huh, decreasing drag by making it turbulent). this moves the point of seperation (of the boundary layer and ball) backwards, so the "wake" of the object is smaller. because its the wake that causes drag. this works at high reynolds numbers (moving fast or with a really thin fluid).

with golf balls, the dimples are the perfect solution, because they can do that without creating wierd flight patterns (like taking your drive to the back of the head...) when there is a bit of spin. this wouldnt really be important in paintball because they dont spin very fast, especially when compared with a golf ball. most of the time you can see the spin while watching a paintball (with two-tone shells).

[Restola]

Forgive my overall lack of fluid dynamics knowledge, but the wake vortices cause a lot of the drag when an object moved through a fluid. Submarine technology for example tries to focus on moving those away from the sub, which decreased drag. Or in an airplane, you have probably heard of wingtip vortices. When those are disrupted by ground effect or winglets, there is a significant increase in performance.

vortices next to an object = bad

[joeyjoe367]

Dimples on Golf-Balls works because a golf-ball is spinning.

Paintballs, on the other hand, are lobbed "knuckle-ball" style, imparting as little spin on the ball as possible.

I think that's why it didn't work. Correct me if I'm wrong.

[giblit]

has anyone actually seen these fly?

[sniper1rfa]

kinda, golf ball dimples are there because of spin, specifically to reduce drag without worrying about spin too much.

its all about the turbulence (vortices, actually little low pressure zones, "sucking" on the ball, as it were) in the wake. the smaller the wake, the less drag, meaning the ball will decelerate slower and go farther.


this is why airplane wings have the blunt end in the front, as it has little to do with drag. the thin, tapered tail allows the wake to be extremely thin.

[pito189]

I once read in Popular Science that they were experimenting with putting dimples on plane wings. I believe it was supposed to increase range, on a flight.

[sniper1rfa]

they did to, but bird excrements made the wings too unstable. :rolleyes:

just like a scuffed golf ball...

[pito189]

I wonder if they have ever heard of a pressure washer?

[sniper1rfa]

no, like one hit and that wings drag went way up. and they only tried it on smaller planes, not large commercial aircraft. they were great, until ANYTHING interrupted the flow across the wing.

[FalconGuy016]

<img align="left" src="http://wings.avkids.com/Book/Sports/Images/golf_01_sma.gif"><img align="right" src="http://wings.avkids.com/Book/Sports/Images/golf_02_sma.gif">

The first one is the air flow over a smooth ball. The second one is air flow over a dimpled ball. The smooth ball has a larger area where the air seperates from the flow around the ball and it creates more drag. The more turbulent flow around the second ball has more air flow around the ball and less area where the air seperates from the air flow and starts swirling around and stuff like that, so less drag.

[ShinyGuy]

Originally posted by sniper1rfa
this is why airplane wings have the blunt end in the front, as it has little to do with drag. the thin, tapered tail allows the wake to be extremely thin.

I was reading about putting things in orbit with railguns. They were talking about how at hyper-sonic speeds you do see a significant decrease in drag with a pointed nose vs. a rounded nose. The problem was that the pointed nose wasn't able to disapate the heat as well as the rounded nose. The conclution they came to was that it would actually be pretty easy to get cargo into orbit with a railgun once we developed material that could withstand the heat a reshaped launch vehicle would be subjected to.

Now keep in mind that this was talking about mach 7+ and isn't really relevent to paintball. I just thought you'd find it interesting. I wish I could that paper now, It was an interesting read.

[paintposse]

i dont think they would work cuz it would make the balls curve dramatically. Its in a popular sicece. I has a buch of stuff in golf and like a shallow dimpled ball would travel farther and with less spin so it would go straighter.

[Smoken]

"the problem is, on something this small, tiny impurities in the surface can do the same thing as dimples. in a fluid dynamics book a read, a 3 inch rough sphere had 5 times less drag at 125 mph winds than a smooth one. and the roughness was in the form of scores only .003" deep. "

So would this mean that the mild roughness of the RPS advantage paints might actually have some value?

[FESTUS33]

How do thos ball's react to a 9 Iron:rolleyes:

[FESTUS33]

Sorry I did'nt mean to make fun
but it was a question begging
to be asked
Festus

[FESTUS33]

Yes I do understand What's Being said here
and there are a lot of good point's being
made.Being a Machinist/ p'balller/amateur scientist
I love watching this kind of information exchanged

[SeeK]

I think this was analysed on rec.sport.paintball and the conclusion was that there wasn't enough time for the dimples to matter. Backspin wouldn't work without high RPM.

[sniper1rfa]

make it a little rougher and you might see some interesting things. however, what i was getting at, is that paintballs may already be rough enough that you wont see any difference between them and a dimpled ball.

they do go fairly far...

[Dragoon]

Alright Tom, youv'e watched as they guys debate it, but what were your findings?

Afterall you stated that it didn't work. Why not?

Douglas

[50 cal]

Sooo Tom, whatever became of the solid shelled p-ball? Give it up, or isn't it cost effective?

[Bront]

I would think that it might actualy be a shell integrity thing, inorder to make the shell able to do that, it'd have to be so thick that it'd be inefective in breaking on it's targets.

At least that would be a problem I'd see, depends ultimately on how it would work.

[Star_Base_CGI]

The answer is simple create a propriatary paintball gun that puts a spin on the paintball from top to bottom.

Spin the paintball top to bottom to give it more lift and more turbulance.

1. Create a special striker and launcher that spins the bottom up when it lauches the paintball.

2. Put some kind of rough irregular surface on the top of the barrel to traction the ball spin up.

3. Make and market the whole system a propriatary size. Make it like .55 That way you have to buy the special gun to shoot the balls and the special balls to shoot in the gun.

Call em VTOL spin ball systems or some *EDIT* Please do not cicumvent the cuss filters, you have been warned. Army like that.

Sadly thats what the world is becoming.

[halB]

star, apg had a system that actually had a spinning barrel to test ball spin on flight i believe, so he could use that. or maybe they just thought of using one. anyways, id like to hear from tom what he found instead of us guessing

[The Frymarker]

Okay what I want to know is how many dimples are on it?;)

[AGD]

This is all being discussed in Deep Blue. Long story short typical paintball spin has little to do with paintball accuracy. The dimples made the accuracy worse. We tried all types of induced spins with no appreciable increase in accuracy.

AGD

[Bront]

Was there any change in distance? From what I can tell, the dimples might reduce drag a bit allowing for a longer distance.

Were you actualy able to make paintballs with dimples? Or just the test balls like you have a picture of?

[aut911]

Just for fun, i think AGD should go to a driving range with either a flatline model 98 or one of those z mags, reason being golfballs or rather the drivers were designed specifically to impart backspin on the golf ball thereby making the range of the golf ball, or air time longer.

Id love to see him at the range though.



FOUR!!
aut

[MINIMAG4LIFE]

so when can we expect a foam rubber ball? something I can shoot at the cat and wife around the house. Maybe make ones that could be used as squeegie balls

[ChucktheMAGician]

Originally posted by MINIMAG4LIFE
so when can we expect a foam rubber ball? something I can shoot at the cat and wife around the house. Maybe make ones that could be used as squeegie balls

Excellent idea, if it could be done? I think this could be it's own thread idea tho. If there are any I want some:)

[Star_Base_CGI]

It dawned on me. The whole thing why this doesnt work.

Paintballs are filled with paint.

Take two eggs and boil them.

Spin both eggs. The raw egg wont spin.

Physics case in short.

You cant spin a paintball because their filled with liquid.

If you shot a solid dimpled ball I gaurantee it would spin up. SO thats why the accuracy sucks.

[SuperBeast]

I noticed that people don't seem to get the concept of fluid dynamics, or have come close but to no conclusion.

For the record, dimples are used a lot. I wouldn't call baseball, football, etc. cutting edge technology. Rather, I would look at F1 racing, naturally aspirated low displacement motors (motorbikes and Honda B series motors).

There are several terms to be looked at here. There is flow velocity, flow capacity and flow quality. Flow velocity would be how fast a fluid travels. Flow capacity would be how much of that fluid travels. Flow quality would be the nature in which that fluid travels.

When air comes out of air conditioners, flows across airplane wings, or is sucked into a motor it travels in layers. This is called laminar flow. The air travels in layers that are "laminated" upon eachother. In the actual paintgun, I doubt air travels in a laminar form, since the air spends time compressed and decompressing. That would be turbulent flow. However, it is the flight of the ball that we look at when the ball is in flight. We want the ball to fly as straight and far as possible (a perfect straight line could never be achieved b/c of gravity).

So, what would cause a ball to fly through air with as little resistance as possible? When two surfaces rub against eachother, they are going to have some kind of friction coefficient. Without going into the math part of it, I can tell you that some surfaces have worse coefficients of friction than others, or they aren't as "slick". In machines, smooth surfaces are good for less friction and easier movement. This is not the case in fluid flow. The smoother a surface is, the worse a fluid will travel over it. B/c the surface is smoother, there is more surface area present to create more laminar drag. When I say laminar drag, I mean that fluid does not flow as well, causing a "pile up". This slows down the flow velocity.

Take the head off your motor and polish everything to a crystal smooth surface. You will destroy it's performance namely because you have destroyed it's airflow or it's ability to breathe. Why do sharks have rough skin?

So how do the dimples help out? The dimples help out because they reduce the surface area that the air flows over. This allows for better flow velocity and less laminar drag.

Don't think a paintball's speed is so minute and small that dimples and the such won't make a difference. The mean flow velocity for most motors is about 240-260 fps. That's a little below what we run the muzzle velocities of paintballs at.

[DeadpoolNSH]

On the topic of foam paintballs, I actually have a few. A friend of my dad's who owns a paintball store gave them to me, so don't ask where you can get them.

Of course, being the scientist that I am, I decided to test the nerf paintballs. In testing them (for the good of science, of course) I shot my mom with one and heard the most blood-curdling scream. The scream could of just come from shock from the noise of the paintball gun plus not expecting to get hit, but after about a year from that event I'm still not willing to ask her(remind her)about it.


I only have about a 100 of them left but I'll try to post a picture soon -Deadpool

[yengese]

I haven't been here in a while, but fluid mechanics and paintball are two of my favorites. Looking at the Reynolds number for a paintball traveling at 300 fps, it is high enough for a rough surface to be more beneficial to the drag coefficient than a smooth one, for a round sphere.( at least according to my text) I am not saying dimples, but perhaps a rough surface might reduce drag a bit. I am too busy at the moment to drop my other studies ( with finals coming up and all) to figure out the math if it will make a difference in range, but maybe in a few weeks. Has anyone done calculations/ experiments with rough paintballs?

[Newbie215]

I say that dimples are a good idea.In reference to baseball I will explain my theory. On the otherhand they may not be you decide


In baseball the ball is rough and matians a coat of air around it. During flight slowly the coat of air is brushed off causing a change in speed. First the baseball travels
much faster because air on air not air on leather. If you throw a biliard ball (pool table ball) it will travel slower. Because it is smooth surface and the coat of air is released much faster. Thus the baseball is more effectient in a rough surface not smooth. In relation to paint balls I beleve that it will have the same effect small pockets of air will get traped in the dimples. On the otherhand the purpution of the paint ball me differ the change. Because we need ,hpa nitrogen or co2 depending one what you use. That will be on the back side of the paint ball possibley causeing a diffrence of balance because air may or may not be heavyer or lighter. Thus mabey causeing a effect of flight. Well thats all the information I have at the moment. I will look into the subject.

[Texas Nate Dogg]

I'd love to find foam paintballs. Do they seriously make them? I've seen plastic ones recently, sold on alot of paintball websites, but I don't want to use those on each other. Foam would be great, but I can't find them anywhere.

[LoveMyMagMoreThanYou]

Originally posted by DeadpoolNSH
On the topic of foam paintballs, I actually have a few. A friend of my dad's who owns a paintball store gave them to me, so don't ask where you can get them.

Of course, being the scientist that I am, I decided to test the nerf paintballs. In testing them (for the good of science, of course) I shot my mom with one and heard the most blood-curdling scream. The scream could of just come from shock from the noise of the paintball gun plus not expecting to get hit, but after about a year from that event I'm still not willing to ask her(remind her)about it.


I only have about a 100 of them left but I'll try to post a picture soon -Deadpool

On the subject of foam paintballs check out: www.lazerball.com

[Lohman446]

Consider this - a sharks skin is rough, and has little v-shapes in it - which has been proven to be more aerodynamic than a smooth surface - the only problem I see with this and paintball, you never know which way a paintball is going to fall into the chamber... making shaping kinda rough to do

[SnarlBuckle]

From what I hear, there is not enough spin on a paintball to make a difference. What if you tested a few of these paintballs with a flatline barrel or something of that nature that would give it an enormous backspin? Combining a flatline with a dimpled paintball could give you even more range.:cool:

[P8ntBallBoom]

Yeah, I don't think spin on a paintball will do much. I know it works for bullets in real guns but those bullets are an entirely different shape.

One problem I see with a dimpled paintball is that it would be near impossiblet to make the dimples consistant enough to have decent shot consistancy. But in theory, if the dimples were perfect, the ball would have considerably less drag.

Thats my 2 cents.

[kapaintballman]

have any of you every heard of the polaris golfball, or somethin like that. it was banned from golf cus it was to good. it only had like a 1/4 inch strip of dimples around the circumference of the ball. this made it go perfecly straight, even when purposly sliced. i saw it on the history channel or somethin. it sounds like the perfect p-ball if it would work

[billmi]

Originally posted by Jack &amp; Coke
I wonder how much that thing would curve if I shot it from my Tippy Flatline...

Damn thing would probably fly around and hit me in the forehead...

A few years ago, Dave Zupan showed me the holes in the ceiling tiles (tall ceiling in the workshop - it's like a warehouse building) made by these balls when they shot them through a gun set up to make backspin.

[Wes Janson]

Up at the Finale, there were a few guys discussing a dimpled ball. According to what they told me, one of the major paintball manufacturers (I honestly don't remember which one..although I think it was JT), had managed to develope a process to produce a dimpled ball, or so they suspected. They claim to have come up with the idea at almost the same time, but apparantly didn't win the patent (or were waiting for results on it). Interesting stories, but I doubt we'll see anything new in the near future.

[homis]

Take the head off your motor and polish everything to a crystal smooth surface. You will destroy it's performance namely because you have destroyed it's airflow or it's ability to breathe. Why do sharks have rough skin?

SuperBeast,

So why did Ford go to the trouble of ExtrudeHoning the SVT Contour intake plenums?

[frop]

The purpose of Extrude Honing is not primarily to polish the ports of the cylinder head. The purpose is the same as conventional porting, get more airflow. It's done essentially by pumping an abrasive slurry through the ports, or at least that's how i understand it. ;)

[Willystyle21]

The reason Aircraft wings are shaped that way is to create lift. Not for a decrease in drag, although incedently that is what happens.

And just humor me on this one.

Now perhaps a teflon based shell with score linea across it. ( think longitude lines on a globe) and a latex based paint, think enough to allow the paintball to spin however will still be bright and shiny on your soon to be X friend.

Just a thought.

[u6e6]

one of my teachers once said to hit my dads car with a hammer to make it more areodynamic...

[spaz7676]

This goes along with drag used to increase range. I was once allowed to try out a little 'dohicky' that when glued to the back of a normal paintball it increased it's range significantly. I shot it out of a modified P68 at 300fps and it had a shot pattern of less than a foot at 150 yards. Some work would have to be done with the matterial it was made out of to make it paintball safe and it couldn't be used in standard paintball guns or loaders, but boy did that thing fly. I can't go into what exactly it is or how it works because it's still a product under development and may even be used by the military in the future. It's probibly not paintball legal for any type of play because it's technically no longer a ball. If anyone knows where I can find the rules regarding the shape/size/mass/hardness restrictions of paintballs I'd be very thankful. I hope these things can be made in a paintball legal way so I can use them for woodsball, finally a reason to have a scope on a paintball gun.

[Vanced]

I am curious to what you are using... but I know Tom already has a set up that uses some fins attached to the back of the ball to make it like a little missle for his military work... I don't have the numbers but if I you can guess the range and accuarcy would be pretty damn spiffy...

[spaz7676]

I am curious to what you are using... but I know Tom already has a set up that uses some fins attached to the back of the ball to make it like a little missle for his military work... I don't have the numbers but if I you can guess the range and accuarcy would be pretty damn spiffy...

Sounds like Tom's got a similar solution to the same problem, probibly even for the same military contract. So in the interest in everyone keeping their various jobs and me keeping my thumbs broken, I'm not going to share any more details.

[justjoshin590]

he made the fn303 a non lethal weapons system powered by hpa, i am interested in how the fins work, cause for woods ball id rather have to load each round by hand and have a extreme range than anything else, i think form the pictures though the shells are actually plastic, not very much information was provided
and it was stored in a clip like the ones for the old tommy guns, the circular ones, it holds 15 shots and comes in stand alone, or can be mounted toa ar-15 style gun

[foot]

I thought about a dimpled paintball as well. However, instead of putting dimples all over the paintball, copy the design of the "happy non-hooker". This is a golf ball designed to eliminate the "slice" that many people encounter. It is made with a dimpled "stripe" around the equator of the ball. The smooth surfaces near the poles provided more air resistance and acted as "fins" causing the ball to correct itself in flight. I believe the only problem is, as I understand it, the stripe has to be oriented in such a way that the smooth sides of the ball are to the left and right of the path of travel and level with the ground for a straight flight.

Have any experiments been done with this?

[RagingCin]

I remeber reading a couple years ago about a paintball shaped like a football to be loaded from a clip type mechanism, this way you can coax a spin with rifling... anyone know what happened to that?

RagingCin
:shooting::bounce:

[LoveMyMagMoreThanYou]

I remeber reading a couple years ago about a paintball shaped like a football to be loaded from a clip type mechanism, this way you can coax a spin with rifling... anyone know what happened to that?

RagingCin
:shooting::bounce:
It didn't fly because it would have required too much modification to existing equipment and why would you want to load clips when you can bulk fill a hopper?

[RagingCin]

well you could get way better accuracy. Plus for all you old skoolers, if you use a pump, 1 shot one kill, right?! one accurate shot or a hopperfull of scattershot.

[LoveMyMagMoreThanYou]

well you could get way better accuracy. Plus for all you old skoolers, if you use a pump, 1 shot one kill, right?! one accurate shot or a hopperfull of scattershot.
I'm sorry, you asked us for the answer to what happened to the football shaped paintball idea. My post was the answer. I'm sorry if it wasn't the answer that you wanted. Basically it was the $

[ThePixelGuru]

It dawned on me. The whole thing why this doesnt work.
....
You cant spin a paintball because their filled with liquid.

Yeah, you _can_ spin a paintball. The Flatline barrel works because a paintball spins. It's all about viscosity.

[hurdlebeast]

^^^

yes and no. i saw a very long and detailed conversation on this somewhere, paintball spinning cannot be controlled because paintballs are filled with a liquid. it's not solid, like a baseball or golfball. try this; throw a baseball at a target. now take one of those solid shelled plastic (but hollow) wiffle balls, and inject water in it. throw it the same way at the same target. same results? i think not. and you have to remember that paintballs are traveling at @ 200 mph, not @40 (which is what an average baseball pitch is).

[LoveMyMagMoreThanYou]

Yeah, you _can_ spin a paintball. The Flatline barrel works because a paintball spins. It's all about viscosity.
Just about every paintball shot out of a barrel spins. The problem isn't spinning, it's amount of spin. The problem is getting a paintball to spin efficiently enough to make a difference. This thread is about dimpled paintballs though and not spin......................

Although to make the dimples make a difference you would have to have some SERIOUS spin, like with a golf ball................................ :D

[Hajari13]

this thread is just thread resurrection after thread ressurection after thread resurrection. only 3 pages after almost three years of existing? dang.

now to be on topic, yea, dimpled paintballs.. cool.

[DoomWithAnXmag]

I was reading about putting things in orbit with railguns. They were talking about how at hyper-sonic speeds you do see a significant decrease in drag with a pointed nose vs. a rounded nose. The problem was that the pointed nose wasn't able to disapate the heat as well as the rounded nose. The conclution they came to was that it would actually be pretty easy to get cargo into orbit with a railgun once we developed material that could withstand the heat a reshaped launch vehicle would be subjected to.

Now keep in mind that this was talking about mach 7+ and isn't really relevent to paintball. I just thought you'd find it interesting. I wish I could that paper now, It was an interesting read.


Hi Mr paintabll store technician can you help me? My rail gun chopps paint real bad at about 45,000 fps. LOL
Im dont see any paint or shell in the breach so maybe its a "rail break"?

[sparktroop]

This may just be redundancy but anytime you try to change the trajectory of a round ball you are going to run into issues like the aforementioned. The only real way to change the trajectory and ballistic behaviors of a projectile would be to change the trailing edge. Like in actual ballistic science. If one were to change the leading edge of a bullet you would find that very little effect is achieved as far as trajectory is concerned. You could cut an "X" or drill a hole into the front of the bullet but not much would happen to distance traveled, drop ratio, or flight pattern.

Altering the aft end of the bullet however has drastic effect! An "X" or dove tailed bullet would be completely erratic in flight pattern and very dangerous. Just imagine a brass slug traveling at 2500 fps and behaving like a Super Swirl out of a Tippmann Flatline!! I dont think I would want to be anywere near it!! Basicaly the point being made here has two factors.

1st - The reason spin from a riffled barrel on a paintball doesn't work too well is because there is no sence of a trailing edge for a trajectory to set a base for flight and maintain that base. Some may say that certain civil war era muskets used round balls and rifled bores. BUT soon after they found that it didn't help too much and developed what we view as a bullet today. It was just loaded like a muzzleloader.

2nd - Unless you change the trailing edge of a paintball, thereby changing the entire manufacturing process thereof you will never achive great success with rifled bores in paintball.

[Automagrt666]

Also, rifling groves the bullets, you can't groove a paintball, it would just pop heh.

[sparktroop]

meant to post that in a different thread but hey.... it works he too :tard:

[leftystrikesback]

I think this thread died because everyone is stuck on the dimples, which have been shown to not work, when the real point is the surface roughness in general.

a paintball with some surface roughness should have less drag than a smooth paintball, given that it's reynolds number is high enough to be close to the transition between laminar and turbulent. The roughness can be very small and come in many forms, not just dimples.

Spin has nothing to do with why surface roughness decreases drag. I have never seen anything in fluid mechanics that ties the effects of roughness to spin, in fact I have seen evidence against it.

http://img.photobucket.com/albums/v205/Leftystrikesback/SphereDrag.gif

this shows a smooth sphere and a sphere with a small wire (or possibly a thin depression) running around the front of it. The sphere on the right has a turbulent boundary layer and much less drag.

The keys here is that the sphere is not spinning (see the rod coming out the back to keep it stable), the roughness is small relative to the size of the sphere, and it is located before the point where separation would normally occur (separation occurs around 80 degrees from the front of the ball)

With dimples there can be many problems including poor contact between the paint and barrel. I don't know why dimples wouldn't work well, but they are not the only way to go achieve decreased drag on a sphere. something as small as the seam of the paintball, or a rough patch at the front of the paintball could cause the boundary layer to be transitioned to turbulent.

Someone mentioned lines scored longitudinally and laterally on the paint, this could be a good solution and one easily tested.

I think that increasing paintball range using this technology is possible and that it shouldn't be given up on, as it seems like it has (until it can be explained satisfactorily why it is not feasible)

A good explanation of the fluid mechanics involved can be found here (http://www.vu.union.edu/~scottg/Senior_Project/Theory%20and%20Analysis.htm) however keep in mind that the lift in his diagram is purely from the back spin shown on the golf ball.

[questionful]

I think that increasing paintball range using this technology is possible and that it shouldn't be given up on, as it seems like it has (until it can be explained satisfactorily why it is not feasible)

Exactly!

I was thinking that maybe Perfect Circle Paintballs could just swap the molds for their polystyrene shells, and try out various surface textures.

http://www.pcpaintball.com/sandra.jpg


http://www.pcpaintball.com/index.html

[Ratt]

I think that increasing paintball range using this technology is possible and that it shouldn't be given up on, as it seems like it has (until it can be explained satisfactorily why it is not feasible)

...yeah? Well, you had better patent it, before "you know who" does... :ninja:

[cyrus-the-virus]

...yeah? Well, you had better patent it, before "you know who" does... :ninja:

Why would voldermort patent it?

[fnherstal]

what if the paintballs were sponge inside inpregnated with paint with the standard type shell would this not fly better


also since someone mentioned rail guns why cant a paintball air powered rail gun be made where the paint goes in one end and is propelled gradually all along the barrel by air pulses coming in vent holes and out the other end

[Surestick]

what if the paintballs were sponge inside inpregnated with paint with the standard type shell would this not fly better


also since someone mentioned rail guns why cant a paintball air powered rail gun be made where the paint goes in one end and is propelled gradually all along the barrel by air pulses coming in vent holes and out the other end

A rail gun doesn't use compressed air to accelerate the projectile: Wikipedia article on rail guns (http://en.wikipedia.org/wiki/Rail_gun)

Using several smaller burst of gas instead of one big one would be inefficient and probably require a prohibitively long barrel.

[fnherstal]

[QUOTE=Surestick]A rail gun doesn't use compressed air to accelerate the projectile: Wikipedia article on rail guns (http://en.wikipedia.org/wiki/Rail_gun)[QUOTE]


yes i know that
i was suggesting that concept of gradually accellerating the projectile all the way allong the barrel could be suitable

[Beemer]

Seven year old thread and seven months since last post. :D

Dont tell no one but there is a revolution on the way. First strike rounds are out and it looks like 50cal balls will try and be reintroduced to the game. :)

[SSP REAPER]

I don't know how the .50 balls will fare. Like many people have previously stated...Rap4 has been around for a few years with their .43 cal stuff and it is not really selling well. All depends on the marketing.

[fishmishin]

Yes, but RAP4 doesn't have the cut throat nature that we have come to know from one of the main backers of .50. I hope I am wrong, but I think it is going to take off.

[SSP REAPER]

Yes, but RAP4 doesn't have the cut throat nature that we have come to know from one of the main backers of .50. I hope I am wrong, but I think it is going to take off.
I will simply boycott buying that shtuff...

[LordOdin99]

For anyone that has seen the Mythbusters episode titled "Clean Car vs Dirty Car", they put surface texture to the test. They put especially looked at golf ball dimples. It seems that regardless of dimple size or object shape, it showed a significant reduction in drag and an improvement in aerodynamic performance. Golf balls traveled farther and cars got better gas mileage.

Perhaps this topic should be reevaluated and discussed further. Was distance ever considered in the original analysis or only accuracy? What about dimple size? Is the raw data still available? The original pics don't appear to be available anymore. I'd like to know in what way the dimpled paintballs didn't work.

[PaintballEngineer]

I can see the idea of a ball being gradually via multiple air ports being incorporated into TK's idea of a air injected marker.

[PaintballEngineer]

It dawned on me. The whole thing why this doesnt work.
...
You cant spin a paintball because their filled with liquid.


Ok, what would the effect of adding a baffle or two have on this? if you put a layer of gelatin between the two haves of the ball would it take a spin better? how might this affect a first strike like round?

:ninja: Just think! If one half of the ball was filled with one fluid, and the other with another fluid that would react with the first... :eek:

[roxcreek]

I caught this on Youtube, and I saw this thread, maybe you guys would take some interest in these:


http://www.youtube.com/watch?v=PKZKuFCvY38&feature=sub

[Frizzle Fry]

cRAP-4 "G.O.L.F." powderballs... http://www.rap4.com/paintball/os/rap4-golf-paintball-powder-version-p-8579.html

"Guided Optimum Longer Flight"? What the hell is that, a madlib? :rolleyes:



Anyway, they TOTALLY thought of it first, what with there not being an AO thread by Tom Kaye dating back to 2002.

[gremlin75]

cRAP-4 "G.O.L.F." powderballs... http://www.rap4.com/paintball/os/rap4-golf-paintball-powder-version-p-8579.html

"Guided Optimum Longer Flight"? What the hell is that, a madlib? :rolleyes:



Anyway, they TOTALLY thought of it first, what with there not being an AO thread by Tom Kaye dating back to 2002.

A wax shell that looks thick as hell. Yeah that will leave more then a powder mark :wow:

[VFX_Fenix]

In all fairness, there is a difference between thinking of a product and actually getting something that "works" to production.

RAP-4 has a history of "inventing" ideas which have already been thought of or even marketed before so believing that they have something truely original is a stretch.

They also qualify that these are training rounds which implies they aren't expecting Joe Paintballer to buy a case of these and start shootin' up the speedball field with them. I'm curious what these things will do out of a Flatline m'self.