Everything you wanted to know about range and accuracy!
LAST REVISED AUGUST 16th, 1999
An article by JLove written
All rights reserved. Copyright Paintcheck.com 1999
Paintcheck receives TONS of mail every day from visitors to the site. Many of these messages ask the questions "what is the best barrel for gun XYZ" or "which gun has more range, gun A or gun B?".
This article is designed to answer those questions honestly.
If this subject matter interests you, please read the ENTIRE article and follow-ups before you send me e-mail. The article touches on physics, but is not meant to be a college course in Dynamics.
Note about ball spin
We all know that backspin will affect a paintballs trajectory, but spin is outside the scope of this article because most paintball guns do not have bent barrels, and I feel that bolt design will do very little to produce spin. Spinning paintballs can also have adverse affects on accuracy, due to the irregular shape, size and weight of paintballs. Time will tell if manufacturers can produce a backspin barrel that will still be accurate. We will leave ball spin for another article. So other than ball spin, what other factors are there?
What affects the range of a paintball?
Newton’s First Law states a couple very important things
1. An object at rest will remain at rest unless some unbalanced force causes it to do otherwise.here is this funny little thing in physics class that you might remember from high school called Newton’s First Law. Newton’s First Law is also called the law of INERTIA. Inertia is basically the force that it takes to move an object, and momentum is the force that the object carries with it as it is moving. You could also think of momentum as the force required to slow an object down as it travels. You will see how this applies to the range of a paintball in a second. I am not a physics major but I am trying to make a simple point.
2. An object in motion will continue in motion in a straight line with constant VELOCITY unless some unbalanced force causes it to do otherwise.If there were no wind resistance or gravity (as in outer space), an object would continue on a straight path with virtually unchanging velocity.
Newton’s Second Law says: F=MA or (force equals mass times acceleration)
So INERTIA is equal to MASS x VELOCITY.
Now lets apply these laws to paintball. If you take a golf ball and a ping pong ball that are the exact same size, and you throw them one at a time as hard as you could, which would go further?
Obviously the golf ball would go further. Since it has more MASS than the ping pong ball, it takes more FORCE (due to its higher inertia) to throw it. This means it has more MOMENTUM than the ping pong ball. If two objects are going the same VELOCITY (300 fps), but one is heavier than the other, which one will go further? The one with more momentum. The ping pong ball and the golf ball may leave your hand at the same VELOCITY, but the ping pong ball will be decelerated by the air much more quickly than the golf ball. The golf ball also take a lot more FORCE to go the same velocity as the ping pong ball when it leaves your hand. To sum it up, there are only two things that will determine how much inertia the paintball has when it leaves the barrel.
Trajectory (arc of the ball's flight)
Some people argue: "my gun has a flatter trajectory than gun A". This is another one of the great misunderstanding among paintball players. There is no such thing as one gun having a different trajectory over another. The proof to my argument rests again with Newton's Laws of physics. This application of physics is called "projectile motion". Basically, the factors that control trajectory are gravity, mass, velocity, and angle of the projectile as it leaves the gun. A projectile shot at 45 degrees will travel the greatest distance possible. An angle greater than 45 degrees will cause the ball to go
higher, but it will hit the ground closer to its starting point. A projectile shot at less than 45 degrees will hit the ground faster due to acceleration of gravity, causing it to not travel as far. Gravity is a constant, and the acceleration due to gravity (32.2 ft/s/s) is the same for all projectiles.
A ball of heavier mass will go farther, remember? So weight of the ball once again plays a part in the flight of the ball, controlling how high and how far the ball will go.
Now lets talk about other factors that affect VELOCITY, since the weight of the ball will not change very much in one case, but the velocity from ball to ball can vary greatly.
Barrel length affects velocity fluctuations
The way that a ball bounces around the barrel or drags against the inside of the barrel can have a profound effect on velocity fluctuations. Ball will touch the sides unevenly sometimes and drag will slow the ball down. The longer the barrel is, the more pronounced these fluctuations can be.
For this reason, a shorter barrel will have less velocity fluctuation than a longer one.
Balls that are out of round will also vary in velocity both because they drag differently in the barrel, and because they have unequal air resistance as they fly.
The barometric pressure changes constantly. As an exaggerated example, is it easy to run through water? Of course not. The weight of the water makes it harder to move through than air does. Slight variations in air density can have the same effect.
What do vented (drilled) barrels do?
Barrels with holes in them do not affect the range of the paintball. Tom Kaye (owner of Airgun Designs) hired the people from Kodak to come out to his factory and shoot some high speed film of paintball guns firing to see what happens when the ball comes out of the barrel, etc. In one test, they had a
stream of smoke right at the end of the barrel. The barrel was SOLID and clear. When the ball emerged from the barrel, there was no "puff" of air that hit the smoke ahead of the ball. The only thing that hit the smoke was the ball. This debunks manufacturer claims that the holes in their barrels reduce air pressure in front of the ball.
Vented Barrels Continued
Another theory by makers of drilled barrels is that the holes somehow equalize pressure in front and behind the ball, making the ball regain shape as it goes down the barrel. The claim is that the ball is more round making it travel farther in the air. What the holes actually do is release the pressure behind the ball, causing it to stop accelerating. They also make the gun quieter. That is all they do.
Airgun Designs used computers to measure the acceleration and power pulse behind paintballs as they travel down the barrel. What they found is that in most paintball guns the ball accelerates in the FIRST 8-12 INCHES OF THE BARREL ONLY. This means that if a barrel is any longer than say 12", it is only slowing the ball down in the barrel. Barrels that are drilled usually only have about 6" of solid barrel. This means their EFFECTIVE LENGTH is only six inches. Shorter barrels have less distance to accelerate in, so the ball sees more force to go 300fps. Once the ball goes past the holes, the air pressure behind the ball is GONE. The ball immediately stops accelerating.
Another popular theory is that the ball "wobbles" through the air like a water balloon. I have even read and heard people say that the front and back of paintballs are almost flat as they travel down the barrel. This is just not true. The slow motion pictures from AGD show the ball travelling down and out the end of the barrel and guess what? They are PERFECTLY ROUND. When the air pushes the ball down the barrel, the air CONFORMS to the shape of the ball, actually "cupping" the ball. This is because the pressure behind the ball is distributed evenly. If the air where to accelerate the ball like a piston, the balls would break, because a typical paintball sees around 3,000 Gs. That’s a tremendous force, but the ball can handle it because the PSI on the ball surface is only around 100psi.
r8 WHICH GUN HAS THE BEST RANGE
Now you know the truth. Negating backspin-inducing bent barrles, the answer is none. What I mean by this is that there is not ONE gun that can out-range all others because if its regulator, valve pressure, air chamber , etc.
If you hear someone say "man that guy's gun really out-ranged me",then you know that this is usually not true. The human perception of the balls coming at you makes it appear that the opponent has greater range than you. This may be true, but only if his velocity is higher than yours and his balls are heavier. That's it. Most players cannot see their paintballs in the air after they travel a certain distance. Usually it is impossible to follow the ball all the way to the target. If the other player is not ducking for cover as you are shooting at him, it may be because he is less afraid of getting hit than you gave him credit for. To you, it looks like your balls aren't reaching him, but in fact they may be, but he just has a lot of nerve. Another thing to remember is that better players will hang out longer in a long-ball exchange like this. You may give up on hitting him because he is not flinching, but he knows that the best chance he has of hitting you is when you are out of your bunker shooting. Suddenly he hits you, and you say "man that guy out-ranged me". This is a tough lesson to take for most people, because they expect other players to duck when they shoot at them. Knowing this bit of psychology will help you to defeat long ball opponents.
Barrel choice usually does not affect accuracy
A paintball does not care what barrel it came from or how slippery the inside of the barrel was after it has left the gun. Accuracy is affected mainly by what happens to the ball AFTER IT HAS LEFT THE GUN. If the ball has paint on it or is dirty, the paint will alter the flight of the ball due to irregularities in the flow of air over the surface of the ball. If wind pushes on the ball, it forces it off course and it won’t go where you thought it would. If the seam is not formed well, or the ball is out of round, the air will not flow evenly over the ball and it will go off course.
Here is a list of possibly factors (in no particular order) that will affect your accuracy:
Velocity too high ( over 280 can cause curving)
Paint in the barrel
Dirt in the barrel
Oil in the barrel (after lubing gun)
Out of round paintballs
Uneven fill mixture (old paint)
Barrel bore too tight
Ball spin does not affect accuracy?
The problem with spinning a paintball is that it is not solid like a lead bullet. You can get the shell of a paintball to spin, but the fill may not spin in sync. Ever spin a glass of water that has ice in it? The ice stays in one place. The fill of the paintball acts the same way, and after the ball leaves the barrel, the ball quickly stops spinning. Tom Kaye suggests that spin in not a factor below 3,000 rpm. I'm not sure I agree with him, but it is important to note that balls that curve badly after going through a dirty barrel do do because the paint/dirt that is on the ball does not allow the air to flow evenly over teh surface of the ball. Aerodynamics of a round ball are not so great because of the turbulence behind the ball, and when you shoot a ball through a dirty barrel it only makes things worse. Any variation in the shape of the ball will make it go off course. Many players assume that a dirty barrel causes a ball to spin, which makes it curve. The paint residue on the surface fo the ball has a more profound effect on the curve of the ball.
Turbulence affects the accuracy more than any other factor
There is a reason why the army does not shoot musket balls anymore. They aren’t accurate. The shape of a sphere going through the air causes turbulence behind the ball that can send it off course very easily. So basically the way that the air travels over the ball will affect it’s flight. Combine that with a paintballs low weight, and you get a projectile that is ill suited for long distance accuracy, and is easily thrown off course. Perhaps this is why so many players are obsessed with the "perceived" accuracy performance of their guns.
The worlds most accurate barrel
Hate to disappoint you, but there is no such thing. What you want to look for in a barrel is one that loads the ball gently, has an effective length of 8-12 inches, doesn't double feed, and has a bore that best matches the balls you are using. When I get mail asking "what do you think of barrel XYZ", I just laugh. There is no one barrel that is the best. If you play in competitions or travel from field to field, you are going to be forced at one time or another to use field paint. You cannot guarantee the balls are round, or that the fill is mixed evenly, or that the shell is not dimpled, or that the size of the ball will match you one "favorite" barrel. My advice on barrel selection is to get a few barrels that seem to perform well with the paint brand and color that you use most often. Having barrels of varying inside diameters will come in handy when the tournament paint doesn't work in your favorite barrel.
The worlds most accurate paintball
Hate to disappoint you, AGAIN, but there is no such thing. EVERY brand of paintball has good and bad batches. They vary slightly in size, weight, and shape. The best way to test a paintball is to drop them from about 4 feet high onto a concrete floor. If more than one or two breaks out of 20, then the shell is too brittle. You can fix this if you are stuck with brittle tourney paint by placing an open glass of water inside the case bag and sealing it up. Leave it for a couple of hours. This basically humidifies the balls and makes them more resilient. Ever seen a wet paintball after a rain? Well this isn't nearly quite that extreme, but you get the idea. The balls will break less in the gun.
Do heavier balls go straighter.
They can, but paintballs are not always round. Spin, weight and shape of the ball. Use heavier balls and they should go straighter, further, and they should hit the target harder.
Which balls are heaviest?
Usually the thicker the fill, the heavier the ball. Waxy filled balls are slightly heavier than other balls.An RP Scherer rep told me that their "gold" series paint has a nasty thick fill and is a heavy ball. That’s what you want to look for. RP Scherer Premium Gold would be my choice.
WHICH BARRELS ARE THE MOST ACCURATE
Now you know the truth. The answer is none. There is not one barrel that will work the best with ALL paintball brands, ALL paintball guns, and ALL paintball colors, in ALL types of weather. There are just too many variable for one to be the best.
Please send us feedbackyour on this article.
thats why you get a freak
i think you left a few things out.
the smoother a barrel is does make it more accurate. which as you would say causes less minor deformaties so the air jets it out evenly. and porting does do somthing other than slow the ball down, at the very end of the barrel where the bal escapes, there is usually a loud pop which is form the air presure escaping. if there is less air pressure "wobling" the ball at the end of its aim in the barrel.
i believe closed bolt guns get more range for two reasons.
mainly because that a blowback gun always releases some air before the ball is actually in the barrel which gives the ball less propulsion.
and the bolt is at rest and less friction due to the breech and form escaped air.
i agree with you that the bolt doesnt matter because the air in the gun wants to return to its normal pressure of 1atm,
if you fire, the air wil always escape the same way.
yeah thanks for the newbie tips...
Hint: They'll go the same distance = no difference in range.
Maybe you can argue some efficiency claims... but I doubt much else.
your rigt i just thought about that right ebfore i read what you said.
and there is no such thnig as simulated closed bolt because "an object in motion tends to stay at motion, but the paintball doesnt have enough time to slow down unless the barrel if smaller than the paint. thusly there is (almost) no such thing as simulated closed bolt.:sleep:
ph yes and by the time the paintbal leaves the barrel it is traveling about 250 fps and doesnt lose speed untill about halfway through its flight. (thats proves what you said)
Doesnt porting reduse turbulance on the ball?
thats what i said it decreases the POP and the wobbke at the end of the barrle and even somtimes within the barrel
Stick with stock?
Does all of that mean I should just stick with my Tippmann stock barrel rather then get a Lapco Bigshot or a Dye Boomstick?
Yeah, if all that is true...why do stock barrels suck?
the have an insuperior finish, they are not slick, usually have some very minor things in them that cause the ball to g wayward,
and usually not much porting USUALLY also most stock barrels arent fit for proper paint to bore matches, if so you will notcie your stock barel firing more accurate than some aftemarket barrels with a bad fit
Its usually going to be the finish of the barrel or the Honing (the inside of the barrel) that makes it not quite as accurate as other aftermarket barrels.
So would there be any difference if I get the Lapco Bigshot or the Dye Boomstick. Or is the Flatline not as bad as alot of reviews I have read? Im just not sure which one to get. I want increased accuracy and every other part of my gun is practically set up to snipe. I even have a laser sight on my Tippmann which with my stock seems almost pointless! It would also be nice to have the extra range of the flatline but are its flaws worth it?
Can someone please respond. Also another barrel I was considering was the J&J Ceramic.
the flatline has barely anything wrong with it as long as you set it up right, its very very accurate at the ranges.
ps, if you need a sight rail after you put the shroud on, lapco is selling one for about 15 bucks, it extends up one side of the shroud
Tippmann Flatline/Lapco Bigshot!
Ok I am going barrel shopping tommorow. I am still not to sure which one to get. I am stuck between the Flatline and the Lapco Bigshot! I hear that the Bigshot basically has the best accuracy of any barrel you can buy. Then I know the Flatline has the longest range. I also here that the Flatline is too unpridictable and doesn't have very good accuracy. Does the extra range make a big difference or does the extra accuracy of the Bigshot make a big difference?
Also the other little question I have is can you mount a AMCO IMP Red Dot site on the shroud of the Flatline? I have a feeling I might end up getting the Flatline if I can just put my site on the shroud without anything else to help it stay on.
Anyways I need to know by tommorow if I can get a responds by then! If not I will ask when I go shopping if my site will fit on the shroud. (I like the Flatline alot more with the shroud) If I can't I will go with the Bigshot.
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