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personman

02-27-2004, 06:59 PM

By popular request I will divulge the inner secrets of bore/paint match ( is was 101 degrees out in the field today so I came in early) [Tom was looking for dinosaur bones in Wyoming, Ed.]

Does having a good paint barrel match improve your accuracy??? YES. How does it do it? Very simple, if your gun shoots with a consistent velocity the paintballs will tend to follow the same arc, thereby improving accuracy. It technically is making your gun more consistent which is a better term than accuracy.

Historically there were many theories about paintball barrel matches. First there was the Tippman theory where they used a very large bore barrel and claimed that the air escaped evenly around the ball and it floated down the barrel without touching anything. They claimed this was the "air bearing effect". Next there was the tight barrel theory that said if the ball seals all the way around the shot will be more accurate. Actual testing has proven both these theories false.

Why match paint to barrel? Going back in time the paintballs were much more inconsistent than they are now, in fact now they are really, REALLY round and half the price. Players found that their consistency/accuracy improved when they used certain size barrels. Unfortunately paint is constantly changing size and this requires different barrel id's to work well.

The technique used to research paint/barrel match is simple and doable by anyone. Testing is performed by blowing a thin powder down the barrel to coat the inside. We used to use Desenex Foot Powder that sprayed on dry. Todays Desenex is a different formulation and doesn't make a powder. Once you have coated the barrel you dry fire the gun once to clear out any extra powder. Lastly shoot one paintball out the gun and inspect the inside of the barrel. The powder will be stripped away everywhere the ball touched. This allows you to see exactly what happened to the ball down the barrel.

If the barrel is too big, the ball ricochets back and forth down the tube. We used to say it looked like Zebra stripes in there. Hence big barrels do NOT create an "air bearing". Barrels that are too small scrape most of the powder off and this creates excessive FRICTION. Tighter barrels that were too long were found to slow the balls down due to this friction. In other words, when you cut these barrels down, velocity went up. Remember the 8-10" acceleration distance, these barrels were 14" long and unported.

The best paint barrel match left two 1/8" wide streaks opposite each other down the barrel. The widest part of a paintball is usually the seam which is also called the equator. With a proper size match only the balls equator touches the barrel snugly on two points. The equator tends not to align itself so the entire seam touches the barrel hence you only get two points touching. So what is happening here that makes this so desirable? We all know paintballs vary in size, this means that there will be slightly more or less friction on the ball depending on how tightly it fits in the barrel. If you use too tight a bore that touches the ball all around, trying to squeeze a bigger ball in greatly increases the friction and changes your velocity. By having the barrel sized to only touch two points, bigger or smaller balls only increase the contact patch a small amount and this gives you better shot to shot CONSISTENCY. To large a bore solves the friction problem but you get back to the ricochet effect.

So this is the story behind proper paint/barrel match. Many of you have commented that the stock barrels seem to work about as good as custom barrels. This is because todays paint is so much more consistent than 10 years ago that the difference between barrels is much diminished. Even the biggest to the smallest barrels don't product that much difference in accuracy IF YOU ONLY COUNT THE SHOTS AT THE SAME VELOCITY. So there you have it, I should mention these studies were done in the early to mid nineties, we have not done any testing lately on two piece barrels etc.

Have you noticed and increase in complaints about paint breakage in the past few months? Do you know that pros with the super tuned guns are dealing with it too? Like to know if it's your gun or your paint? Well read on because this is my fourth installment of Tech Tips designed to inject your brains with knowledge.

Paintballs are made in a 100 year old crude but finely developed process that no one thought would work. The fact that paintballs are as good as they are is really amazing. They are made by pulling two sheets of gelatin, sort of like the Jello stuff, through two pinch rollers. The rollers have holes in them which act like cookie cutters and stamp out the round shape and seal the edges. This is equivalent to taking a piece of round pipe, heating it up the end, press it into a plastic bag laying on the table and trying to seal and cut the plastic at the same time. Now you have to also fill it with goo. We'll try the same thing again but this time you stick a needle between the bag layers, then press the pipe into the bag and seal the needle in the process. Here is the tricky part, you now fill the bag full with goo but don't press hard enough to cut the bag just pinch it closed and seal it. Right when the bag gets completely full you yank out the needle and finish cutting and sealing the bag. Your left with a flexible bag of goo, maybe it leaks maybe it doesn't.

In paintball manufacturing the balls come out of this process all rubbery, flexible and oversize. They really look more like water balloons than paintballs. In order to get them stiff and round they are dried carefully in a tumbling process that takes the moisture out of the gelatin. This is the key point, getting the moisture out. You all know that humidity affects your paint and if you get it wet it goes to hell. Perhaps you have seen paintballs sitting under a bush at your field that look huge and rubbery, that is the extreme example.

In the past couple years or so it has been fashionable for pros to demand more fragile paint that will always break on impact. This idea of more fragility has spread around the industry and a lot of the paint appears fragile now. I am concerned about this because it is putting a lot of blame on all the guns and pressure on us designers to fix it. Besides that, paint that gets old or is not properly stored tends to get more fragile. So now you can have bad paint being passed off as tournament quality because "that's how they like it"

So how do you know what you have and how do you test it? That is the subject of this tech tip. It is actually a tried and true process called a Bounce Test. We have used it for ten years to determine what type of paint we have and how it will work in the guns. In order for this test to have significance you must do the same thing every time and don't cut it short. Start with 10 paintballs, take one paintball and drop it from about 6 feet and let it hit a hard concrete surface. Catch it on the first bounce, do not let it bounce twice in one drop. Now with the same paintball drop it again from six feet, catch it and repeat until it breaks. Mark down how many bounces it took to break that paintball and then repeat with the other 9 balls. Throw out the high and the low numbers and average the other 8. This gives you the "bounce number" for the paint. Simple but effective. Make sure you use a hard surface not a wood floor etc.

So what does this bounce number tell you? 1-2 bounce paint is super fragile and will break down the barrel in most guns just from the air blast. It will also break in your tubes if you don't pack them tight. 1-2 bounce is pretty worthless paint, you can get it at Wall Mart. 2-3 bounce is considered fragile tourney paint, breaks on people and in the guns too. We are now seeing some field paint at this level. 4-6 bounce paint is good all around and considered fresh. It goes through most guns very reliably but will bounce more often on long shots. 6 and higher used to be considered the best tourney paint in the early 90's because it would go through the guns and never break. Nelson paint was very notable at 8-9 bounces. This paint is hard to find these days but still fun to shoot. Great for big games and when you just want to shoot a lot and not worry about anything. The best thing about high bounce paint is that as it gets older it still works pretty good. 2-3 bounce paint goes to unusable 1-2 bounce pretty fast.

So now that you know what you have, what do you do about it? Well we have a fix for that too. Back to the idea of moisture, by controlling the moisture in the paint shell you can adjust the bounce level but only to a certain extent. If your paint is too fragile you can generally move it up one category by setting the bag on a table, opening it up and placing a standing glass of water inside the bag and closing it back up. Let it sit overnight and your paint should move up one bounce category. If it's too bouncy (not likely lately) then you can leave the bag open over night and unless your in a humid area the paint should get a little more fragile. All of this is true for standard gelatin paintballs, we have NOT tested the new dry paints so we are not sure if the same thing applies. Test it yourself and let us know.

My opinion is that the pendulum has swung too far the other way right now and paint is too fragile. This fragility is masking poorly stored paint and millions of rec players are dealing with broken paint when they shouldn't have too. When doing the bounce test note the variation in how many bounces it takes to break the ball. If it ranges from 1-8 then it's inconsistent and will give you problems. Good fresh paint consistently breaks between 4-6 bounces and is worth what you pay for it. As with many things in paintball this test is under utilized to diagnose problems. Take it to heart and show your friends, a little knowledge goes a long way. I want to hear about you guys putting this info to use!

That should give you something to read about.