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synreal
01-10-2002, 12:02 PM
i am just curious if anyone knows roughly what a paintball weighs.

i am trying to figure out about how much energy is disapated by your body when you get shot at relatively close range (200+ fps). someone has to have taken the time to do the math on this before.

manike
01-10-2002, 12:16 PM
A paintball weighs approx 54 grains. Or it did last time I made measurements (many years ago) different brands weigh more or less. From about 51-55 grains if I remember correctly.

Get the heaviest paint you can :)

I have done the math on this before. Actually the reason we have velocity limits is not because of velocity but because of energy levels. The legal 'non lethal' (at least outside of the military non lethal weapons...) energy is 12ftlbs of energy.

The equation for energy is:-

(speed(ft/sec) X speed(ft/sec) X weight(grains)) divided by 450240

You can see that this means most paintballs have just over 10,7 ftlbs of energy. The limit of 12ftlbs is reached at just under 320fps if I remember correctly. In the Early days we used to chrono at 320! But it was brought down to 300 as it's a nice round number and under the safe/legal limit. In England if your gun went hot over 320 then in theory you would have a firearm and be liable to many years in jail...

manike

manike
01-10-2002, 12:21 PM
One point to add. The energy is obviously at the point where you chrono the ball, as it flies down field the velocity and thus energy is reduced. If you get bunkered though you will be taking all that energy.

Often getting hit by a higher velocity ball actually hurts less... Why? Because it is more likely to break. If it breaks it dissipates is energy in the spread of the paint and less into you, where as if it is going slower and bounces it puts the energy into a concentrated spot and has a huge change of momentum.

I'm guessing most people have noticed that bouncers hurt more. That's why :)

manike

Butterfingers
01-10-2002, 12:26 PM
Or we can all use the metric system and use the equation:

KE= 1/2m(vv)

(vv)= v squared in meters-per-second
m= mass in grams

Yeah Im an american and I use the metric system, I dont beleive in the English system, heck even the English don't use the English system anymore :)

Thordic
01-10-2002, 12:26 PM
Zap Performance Plus weighs 3.3 grams per ball, or around 0.11 ounces.

Thats roughly 8 month old paint, though. However, they shouldn't have swelled much, they were stored in an airtight jerrican.

If KE= 1/2m(v^2) is correct, then I get 27592.20288. What unit is that number in though? And did I just screw up my math? Busy at work, cant doublecheck :)

synreal
01-10-2002, 12:28 PM
thanks, i now have a definative answer as to how much energy my 'boy bits' can absorb without suffering catostrophic damage (other than me falling to my knees and cursing the gods ;) )

i took one to the boys last night (from well under 10 yards) and there was no break, so 'they' absorbed the full force of the shot.

manike
01-10-2002, 12:31 PM
Oh and another point :) while I am at it. You can see that the energy relates to the square of the velocity. This is why running as close to the velocity limit is VERY important for getting your maximum range. There is a greater difference between a gun running 295fps and one at 285fps than one at 285fps compares to 275fps :)

Maths:-

(295x295x54)/450240=10.44

(285x285x54)/450240=9.74

(275x275x54)/450240=9.07

Diff 295-285=1.3ftlbs
Diff 285-275=0.67ftlbs

This is one reason that I work to make my guns as consistant as possible so that I can safely run them as close to the velocity limit as possible. That way I DO have a major competitive advantage.

I guess maybe I typed more than you were looking for, but I find this interesting and hope someone else out there does too...

manike

synreal
01-10-2002, 12:33 PM
nope, just the right amount of info, very useful stuff

Bonx0007
01-10-2002, 01:26 PM
You guys just did all those fancy computations in order to figure out how bad Synreal got shot in the nads. WOW.;)

synreal
01-10-2002, 01:30 PM
not the nads, just the frontal part of the 'equipment' ;)

i also got shot in the back from potatoboy who happened to be on my team at the time //shakes fist in defiance//

Bonx0007
01-10-2002, 01:41 PM
Friendly fire is the worst. One time in a rec ball game I got all the way behind the enemies position and I got tagged by my own team. That really sucked. oh well.:rolleyes:

synreal
01-10-2002, 02:23 PM
it wasn't really his fault, the paint he got was REALLY tiny, like .67X tiny, it was curving every which way right out of the barrel.

ronron2112
01-10-2002, 02:32 PM
butterfingers: in school the teacher teaches us that way, probably because its easier to do than the other way...

waayyyyyyy too many numbers for little ronron2112.... the only number i need to know is 290...

Nitroduck
01-10-2002, 02:34 PM
Paintballs are about 3.1-3.25 grams......

Really varies on manufacture/boresize/fill. Some paint has a thicker fill than others allowing a higher kenetic energy.....And more accuracy/range

ThePatriot
01-10-2002, 04:10 PM
I was on an airsoft site and some people did this...i cannot give specifics, but when a paintball strikes a person the average force is 12J, so next time u get hit odds r ur being hit with 12J of energy....

Potatoboy
01-10-2002, 04:15 PM
Originally posted by synreal
i also got shot in the back from potatoboy who happened to be on my team at the time


But I made your back all peachy. Doesn't that make it all better?

Vegeta
01-10-2002, 08:10 PM
I heard 6 grams, but that was in an old APG, so I belive u ppl first.


Is that 12 Joules of energy? neato.