wabi wrote:Please don't take this wrong - I'm just asking.
How does the stirrup vibrate and cause noise on a shot?
I've watched a slo-mo video of an Excal being shot and I can't see the stirrup vibrating.
http://www.youtube.com/watch?v=rmntwlIhco4
There are several videos in the series and I can see the scope jumping around, the string dancing, the arrow retention clip going wild, but the stirrup looks solid.
I would never take offense at a question from you wabi, and understand why you ask that question. Though you may not be able to see the vibrations on the video, you have to consider the size of the part. The smaller the part and more ridged it is, the harder it would be to see pronounced vibrations on that part, however, you would be able to feel the vibrations whether you could actually see them or not. It stands to reason that with as much energy that a crossbow releases at the time of shot, that energy has to go somewhere after being released. That energy will be transferred into and throughout the crossbow.
To prove this, simply cock the crossbow and then (after putting the safety on) remove the stirrup from the crossbow and shoot it. You should have no problem seeing and hearing the difference during the shot.
A much simpler way of testing for vibration noise in the stirrup is to simply take an ink pen or similar device and strike the stirrup with it. If you do not already have tape or some other medium on the stirrup it will be similar to striking a tuning fork. Not only can you hear the vibrations but you will also be able to feel the vibrations as well. Placing a dampening material such as this limbsaver wrap on the stirrup will take a lot of the vibration out of it dissipating it throughout the material instead of the metal of the stirrup.