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Paintball impact with stonger Gun

  1. Jul 20, 2009 #1
    We went paint balling with 17 friends. At dinner we had an discussion if a stronger weapon would result in stronger hit.

    The question is?

    Is their a maximum of energy a paint-ball can give to your body, independent of speed or energy.

    In other words...Will a bigger gun hurts more than a smaller gun with the same type of balls, because the balls will always break on impact.

    This a very hot issue:) Some people will lose/win a dinner:)

    Thanks in advance.
    Last edited: Jul 20, 2009
  2. jcsd
  3. Jul 20, 2009 #2
    If you have ever played paintball at a field you will have likely had to chronograph your gun, the maximum (standard) speed is 300 feet per second because too much faster and it can become fairly unsafe (and leave some pretty gnarly bruises). So yes, if you shoot a paintball faster it will have more energy when it strikes them. Does it hurt more? It's hard to say, if the shell does not break on impact it can hurt allot, even if it was not going too quickly. However, if it breaks instantly at a very high speed the energy would be distributed over a larger area and may seem to 'hurt' less.

    You are both somewhat right I guess.
  4. Jul 20, 2009 #3


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    Even though the shell breaks, it (or rather, its pieces) as well as the contents continue to move forward. Yes, a more powerful gun will hurt more. The energy has to go somewhere; energy which goes into breaking the shell is not lost, it eventually goes into you.
  5. Jul 21, 2009 #4
    Thanks for your replies...

    Is their a way to prove this, with e.g. a calculation or something else because the two reaction so far seems to contradict each other.


  6. Jul 21, 2009 #5


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    As much as I like math, equations aren't going to prove anything to everyone's satisfaction. This is one to be settled by (CAREFUL!) experimentation. I wouldn't go above 300 fps, as indicated above, not only for safety reasons but also in many areas it's the maximum allowed by law. You should be able to note a considerable difference between 250 fps and 300 fps, though.
  7. Jul 21, 2009 #6
    Well, negitron is right... But there is a super obvious example, the momentum equation.

    It is simply (p = m*v) where 'p' is the momentum in kg*ms, 'm' is the mass in kilograms and 'v' is the velocity in meters a second.

    SO... if we assume the average weight of a paintball is roughly 0.003201 kilograms;

    (for 300 feet per second)
    0.003201 * 91.44 = 0.29269944 kg*ms

    (for 250 feet per second)
    0.003201 * 76.2 = 0.2439162 kg*ms

    So, it should hurt ~20% more... I guess.

    The only question is what happens when the paintball breaks on someone. Not much, it still has to deposit all of its energy into the person/object it struck. Only the contact surface area will be larger than if it had not broken so, to a person, it may feel like it 'hurt' less. But if we assume the paintball always breaks (it usually does unless its a graze) all of this last bit is void anyhow.

    To make this even MORE obvious, imagine an paintball traveling at half of the speed of light, break or no break, it's going to be one hell of a deadly hit. So, yeah, it goes faster, it hurts more.

    EDIT: Also, I dont see how negitron contradicted me with his post.
  8. Jul 21, 2009 #7
    I like negitron's idea. Go shoot each other with paintball guns of ever increasing muzzle velocity. First one to quit gets called a wussy. Don't worry, it's in the name of science ;)
  9. Jul 22, 2009 #8
    Thanks you all,

    Sorry James Leighe, my mistake..thanks for the math’s. If this doesn't help us to get out of this discussion we will certainly use plan B(Break all Bones with paintballs till somebody say stop.....) in the name of science of course:)))))


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