Barrel Efficiency, Tech Tip #1

[keebler]

well actualy chuck at co paintball in toledo ohio showed me a pic of this 3 foot (i think it was that long) barel he messes around with his angel. lol, that thing might do the job.

[hitmanng]

<font face="Verdana, Helvetica, sans-serif" size="2">Originally posted by M-a-s-sDriver:
Well, I've been thinking about this, and the conclusion I come to is that there painty-ball thingy Does not, cannot, would not, and is completely unwilling to go 50,000 feet per second, no matter how much to beg. The problem with the formula (50,000 x.006 =300) is that you are assuming the paintball travels 300 feet in .006 seconds, because that is how fast it would have to go in that amount of time to hit 50,000 fps. A mile is 5280 feet. For this logic to work, it means that poor little paintball has to go 2840 miles per hour. That is approximatly mach 4. That is the muzzle velocity of a .308 sniper rifle. (ARMY, step in here if my ballistics are wrong buddy). A paintball has a muzzle velocity closer to an arrow released out of a 70# bow.
Now, If that ball got anywhere NEAR 50,000 fps, you would have to decelerate the poor thing back down to 300 fps somewhere in the barrell. Unfortunatly, all the two piece extremme porting in the world won't do that.
Sorry guys. The math is wrong here. Think about it some more and you will see.
Respectfully, Brent Jackson, PFB.</font>

Sorry M-a-s-sDriver,
But you have your units wrong here. The ball does not travel 50,000 ft/sec the speed of sound is 1,088 ft/sec and the paintball does not even approach the speed of sound.

It does however excellerate at a rate of 50,000 ft/sec/sec. Acceleration is the rate at which velosity changes. This means for every second that passes the balls velosity would change by 50,000 ft per sec. So in 0.006 seconds (the amount of time it is in the barrel) it changes from 0 to 300 fps. The math stands as
50,0000 ft/sec/sec X 0.006sec = 300 ft/sec
Please note the units used.
Please do not take this the wrong way. I am only trying to explain and if it sounds condicending I am sorry. Physics is one of my favorite things.
Hitmanng


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"I would rather hit once than miss 140 times."

[M-a-s-sDriver]

I'll buy that, math-wise. But that would require that the ball go 300 feet in .006 seconds. Rather, in that amount of time it really only goes about 10 or 12 inches, at which point it has reached it's terminal velocity. Now if you carry out the math, and assume it goes 12 inches, or 1 foot in .006 seconds, 300x.006 is 1.8 seconds. Now that still does not equal 300 fps, obviously, but we are getting close. So far I am off the actual fps number by 80%. The other method is off by about 10,000 %. Even if you use the arguement of RATE of acceleration, that would mean that that paintball would have to reach terminal velocity in roughly 1/180,000 inch, then maintain that velocity through the barrel. The simplest way to visualize this , again, is with a bow and arrow, since the terminal velocity of an arrow and a paintball are almost identical. A typical arrow is approximatly 28 inches long, which makes it about twice as long as a freak barrel, which I have. That means, according to the 50,ooo fps principle, that somewhere along it's path on the bow, it hits a rate of 25,000 fps, which is impossible. Part of the problem here is the expression of 'rate'.
Naturelly, if you CONTINUE to accelerate an object, at any rate, it will achieve the desired terminal velocity. But we have only a small length to propel the ball, and it's terminal velocity is the highest speed it reaches.
Now remember guys: You are thinking I am a completely brilliant person to have these great thoughts, but I have consumed 4 Sierra-Neveda Pale ales, So my thinking is on an entirely different level from yours. (you have to determine which level though).
Again, with the utmost respect to those here, Brent Jackson, PFB.

[hitmanng]

<font face="Verdana, Helvetica, sans-serif" size="2">Originally posted by M-a-s-sDriver:
But that would require that the ball go 300 feet in .006 seconds. </font>

No actually it says 300ft/sec so it would take 1 sec to go 300 ft.
Say the barrel is 12 in or 1ft long. To traverse it in 0.006sec the average speed of the ball is
1 ft / 0.006 sec = 166.7 ft/sec.
(Actually the barrel must have been about 10.8 in long so the average was 150 ft/sec)

<font face="Verdana, Helvetica, sans-serif" size="2">Rather, in that amount of time it really only goes about 10 or 12 inches, at which point it has reached it's terminal velocity. Now if you carry out the math, and assume it goes 12 inches, or 1 foot in .006 seconds, 300x.006 is 1.8 seconds. </font>

Look at the units here. 300ft/sec x 0.006 sec = 1.8 ft. This is true if the ball were moving at 300 ft/sec the entire time it was in the barrel it would have traveled 1.8 ft but it was accellerating so only reached 300 ft/sec as it left the barrel.

<font face="Verdana, Helvetica, sans-serif" size="2">Now remember guys: You are thinking I am a completely brilliant person to have these great thoughts, but I have consumed 4 Sierra-Neveda Pale ales, So my thinking is on an entirely different level from yours. (you have to determine which level though).
Again, with the utmost respect to those here, Brent Jackson, PFB.</font>

I do agree you are on a different level at this point LOL.

Use the units in the equations it helps. The ball never goes 50,000 fps it could not. It never passes 300 fps. Acceleration, Velosity and distance are very different and the numbers do make sense.

The accelleration in the barrel is 50,000 ft/sec/sec.
The average speed is 150 fps with the lowest speed being 0fps and the highset speed being 300 fps.
The distance is 10.8 inches and the time is takes to travers it is 0.006 seconds.

Hope this helps,
Hitmanng

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"I would rather hit once than miss 140 times."


[This message has been edited by hitmanng (edited 07-21-2001).]

[Motomaz]

I never knew that I could learn so much from paintball on a website. This is so cool about the barrles. I found that the stock barrle isn't really that bad but it may break paint more then a aftermarket barrle will. I have a 12 inch boomer and it seems that I never break paint. If I do break paint it's on people

Andrew