So who has it?

[BigEvil]

Before we build a system that can measure each and every ball, you have to look at what and where you are trying to measure.

Knowing the velocity of every ball won't necessarily indicate accuracy. A very short, over-bored barrel should give good velocity consistency but stinky accuracy.

Also, distance from the muzzle is a big factor in paintball accuracy and down range velocity. Spheres don't make the best projectile, but lumpy or wet balls are much worse. A "clean" ball will fly farther than a "dirty" ball. The point is that flight deviations caused by the barrel and ball can equal or exceed the deviations caused by muzzle velocity changes in a given distance.

I would also think that even with exact data on each ball, in the end you will be bringing the results back to statistics, if only to prove the point.

So... yes, how about some "better questions"?

I think what he is trying to get at, is which gun can perform best over a long fast string of shots as far as holding velocity - not necessarily accuracy. Barrels, paint, and long range accuracy would be irrelevant. You would just want to know at what speed each of those blazing fast paintballs would be at.

Once you can do that, then the other variables could come into play. But say we take an Emag and an autococker to test. We would set them both up for the same ROF, using the same tank, barrel, loader and paint. Then we fire each one 15 balls per second over this imaginary device and observe the results.

These are results that are as of right now impossible to determine with current equipment (to the best of my knowledge).

[Spider-TW]

I think what he is trying to get at, is which gun can perform best over a long fast string of shots as far as holding velocity - not necessarily accuracy. Barrels, paint, and long range accuracy would be irrelevant. You would just want to know at what speed each of those blazing fast paintballs would be at.

Once you can do that, then the other variables could come into play. But say we take an Emag and an autococker to test. We would set them both up for the same ROF, using the same tank, barrel, loader and paint. Then we fire each one 15 balls per second over this imaginary device and observe the results.

These are results that are as of right now impossible to determine with current equipment (to the best of my knowledge).

If cockerpunk will ever get his high speed camera, it would probably work, manually at least. I bet he's still taking donations. (who isn't?)

I understand the original question and I am interested in the answer. I was just looking at Beemer's question of whether we thought it would matter. What I was trying to say is that at some point it will not matter. +/-10 fps at 10 feet doesn't matter for example. Even a wet barrel will usually make that. +/-1 fps at 100 feet doesn't matter. It's a logarithmic doesn't-matter-curve.

Without doing the high speed test first, we could probably figure out what a significant deviation would be. I have certain expectations of markers and the experimental results, but if you told me the opposite of what I expect, how would I know if it mattered? The answer to that is probably in some of cockerpunk's accuracy data.

[esperto96]

All of this talk of knowing/not knowing the exact velocity of a single ball in a string of shots reminds me of the Heisenberg Uncertainty Principle in Physics. Individual paintballs are certainly easier to determine position/velocity than individual protons or electrons. Sorry, kind of random.

I've found that my A-5 over the chrono tends to be more consistent in single shots (+/- 2 FPS) than my my mags (+/- 4 FPS). However, in game, I find that I get tighter shot groupings overall with the mags. Anecdotal evidence and hardly scientific. It might just be that my mags have a better ergonomic fit with my body than the A-5. Or maybe I just believe in it more so the magical elves in the gun work harder to please me

[211]

I think we can come to a reasonable test with current equiptment
We are looking for a chrono reading mid rope to compare to a single shot reading, so....
why not just put the marker in full auto (eyes off if appropriate) so that it is cycling at a good rate, then feed it a paintball, while firing, every second or so (whatever rate the chrono will read)
It doesnt give a 100% accurate 15 readings in a 15 bps rope, but it would give a reading that is a good representation of what the marker is doing while firing at high rates

the only issue I see with doing this is feeding it, gravity feeds about 12, so loading a single paintball into a gun firing 15 bps is going to take some kind of a trick. any ideas?

[AzrealDarkmoonZ]

How many balls do you want to read the FPS? I have a chronograph next to me that will read a 20 ball string. After that its a circular buffer, mine is now 5 years old and there are some that can measure to the hundreds. Hell mine even records to the tenth of a FPS.

Az

[Hilltop Customs]

Make a barrel mountable break beam sensor that attaches like a silencer. We know the diameter of the paintball, so as long is the ball passes dead center through the sensor you can calculate its velocity by the duration of the pulse of the sensor. Hook it up to a computer, record the pulses and you will be able to calculate the velocity of any and all shots in a string.

Now @ the OP....build the break beam silencer doohickey, hook it up to the board of the gun and allow the gun to automatically control dwell to adjust the velocity based upon the previous shot velocity/ROF data. Do that and you have the most velocity consistent marker @ any ROF. BUT it still be completely dependent on the consistency of the paintballs being fired.



Now the easy, everyday version of this test.....fire a locked down marker at a long range target.(preferably indoors or with no wind) Since a lower velocity ball will take longer to strike the target, the ball will have dropped futher than a higher velocity ball. So, a shot grouping of any ROF with high variation in velocity will have a vertically oblong ellipse shape. When conducting this test the first shot has to be thrown out so use a different colored paintball for the first shot. This way is not nearly as accurate as the break beam test, but IMO that kind of fidelity doesnt really matter on a paintball field.

[Beemer]

How many balls do you want to read the FPS? I have a chronograph next to me that will read a 20 ball string. After that its a circular buffer, mine is now 5 years old and there are some that can measure to the hundreds. Hell mine even records to the tenth of a FPS.

Az

We want to read the FPS on say ten to fifteen balls in ONE SECOND. What Chrono do you have and in what time frame will it read that twenty ball string.

[Hilltop Customs]

On second thought even the slightest variation in ball diameter will result in a pretty significant change of the calculated velocity so using it for a test might not be the best choice.

I wonder how accurate those sensors are....a .69 diameter paintball traveling at 300fps would only block the sensor for ~0.000192 seconds. To measure 1fps changes you would have to be able to measure at least 0.0000005s increments. Yeeeeaaa might not work too well, cool idea bites the dust.

[Beemer]

On second thought even the slightest variation in ball diameter will result in a pretty significant change of the calculated velocity so using it for a test might not be the best choice.

We can over come those variables with a given size and weight round nylon ball and a given barrel bore.

[Hilltop Customs]

On third thought, if using 2 sensors over a range of say a few inches the accuracy of the sensor would not need to be nearly as small. The larger the distance between the senesors the less accurate the sensors would need to be....the only requirement is they are accurate enough to "notice" the ball breaking the beam. Of course this kind of ruins the idea of marker integration, but it would still work for the testing portion.

I guess this is turning into the same idea as using a high speed camera and a measuring backdrop, but all contained into a 2" or 3" barrel mountable device.




Sorry, missed your post Beemer. Using nylon balls would work, but I was kind of hoping to lead into the automatic dwell/velocity adjustment idea while using normal paint. The nylon balls would be perfect for testing though.

After playing around in execl for a few seconds; when using a single break beam sensor to calculate the velocity based upon the diameter of the the paintball, a change of overall diameter from .685 to .690 only results in a calculated difference of 1 to 2 fps.....not nearly as bad as what I first expected. Makes sense though ~1% change in diameter would result in ~1% change in calculated velocity.

[BigEvil]

On third thought, if using 2 sensors over a range of say a few inches the accuracy of the sensor would not need to be nearly as small. The larger the distance between the senesors the less accurate the sensors would need to be....the only requirement is they are accurate enough to "notice" the ball breaking the beam. Of course this kind of ruins the idea of marker integration, but it would still work for the testing portion.

I guess this is turning into the same idea as using a high speed camera and a measuring backdrop, but all contained into a 2" or 3" barrel mountable device.




Sorry, missed your post Beemer. Using nylon balls would work, but I was kind of hoping to lead into the automatic dwell/velocity adjustment idea while using normal paint. The nylon balls would be perfect for testing though.

After playing around in execl for a few seconds; when using a single break beam sensor to calculate the velocity based upon the diameter of the the paintball, a change of overall diameter from .685 to .690 only results in a calculated difference of 1 to 2 fps.....not nearly as bad as what I first expected. Makes sense though ~1% change in diameter would result in ~1% change in calculated velocity.

AHHHHHHHH HILLTOP CUSTOMS MADE MY HEAD HURT!!!

[Hilltop Customs]

its not nearly as complicated as it sounds....I'm just bad at putting thoughts into clear and concise wording sometimes.

It would require either 1 or 2 breakbeam sensors just like the ones used for the eyes of electronic markers. Just record the pulses generated by the photoresistors and you can calculate velocity either based upon ball diameter(diameter of paintball/the duration the beam is broken) or based upon two sensors(distance between 2 sensors/time between sensors being activated).


Now on to the more fun stuff.
At first I was thinking something like a pinpoint laser would be required as an emitter, because the numbers generated by the calculations would be inaccurate(but yet still extremely precise) because of the width of the "beam" emitted by the light/energy source. Reconsidering it, since we are only interested in the variation of velocity and the data would be uniformly inaccurate, a simple calibration factor would be all that is required to adjust the accuracy to the correct FPS. That probably lost some people lol.

I really like the idea of self adjusting dwell/velocity based upon the breakbeam, but if you happen to get some paint on the photoresistor the feature becomes broken and would have to work solely off of historical data until the sensor and emitter are cleaned.

If you really wanted to go crazy you could eliminate the need for ALL regulators using this system along with an input pressure sensor....you would just need a marker designed to take the input pressure. A redesigned mag valve would work pretty well, but most of its features(reg assembly, dump chamber, bolt catch) would not be needed. Literally all you would need is the bolt, power tube and the on/off. There would also be a need for a precise electronic way to control the on/off.


Thoughts anyone?

[MANN]

Thoughts anyone?

This is paintball.

[Hilltop Customs]

This is paintball.

Paintball? THIS IS AO! (kicks MANN into the giant pit)

/lame 300 reference

[MANN]

/lame 300 reference

on the note of what you were talking about earlier. there is a thread somewhere on AO where that Idea came up. There was an interesting conversation about it. I think that the end conclusion was that it would cost too much to become pratical.