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How to measure recoil force?

  1. Feb 10, 2010 #1

    I'm interested in measuring the recoil force of a weapon.

    Anyone got any ideas om how to go about doing this? I was thinking of using a load cell mounted to the weapon in the horizontal plane, but at the same time the weapon needs to operate more or less freely, which will be difficult with the weapon mounted to a load cell (not very much travel there).

    I was also thinking of mounting a spring between the load cell and weapon to allow for more travel of the weapon, and this is more or less this idea I'm working on now. Will this work and give me the right measurement? Will I need to know the exact spring constant and distance travelled and do some calculations, or will the load cell reading be the correct one regardless of the spring?
  2. jcsd
  3. Feb 10, 2010 #2


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    Science Advisor

    You don't need to know the spring constant. You are measuring the force! If you were just measuring the deflection, then you would need it.

    I would say the spring is a better way to go. The only little tough part is to make sure you have something guiding and holding the weapon so that it only moves linearly. This also assumes that you know the actual path the recoil is taking, but I would think any guess to that would be pretty close and not induce too much experimental error.
  4. Feb 10, 2010 #3

    Doug Huffman

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    Yes, measuring the force with a dynamometer is the way to go. But watch the impedance and time related values because you want the instantaneous force and that's a bit harder to get.

    If you're a shooter and thinking of recoil then you need to read up on impetus and momentum and stuff.
  5. Feb 10, 2010 #4
    I've got a fixture to mount the weapon in making sure I get linear movement (horizontal).
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