Today I tried a lighter weight bolt.  It tipped the scales at 5, 825 grains (377.5 grams), and was clocked going at 345 feet per second.  This yields a muzzle energy of 1540 foot pounds.  Compare this to that recent series of shots , where we had a heavier 6893 grain bolt clocked at an average velocity of 300 fps,  for 1377  foot pounds of energy,  and  it does appear that Firefly prefers these lighter bolts for delivering a punch.

More speed, more energy, a flatter trajectory:  what’s not to like?    So far I have only been able to record this fairly boring video of our new found velocity gains.  There was no particular target I was trying for, it’s  just a flight test into the back stop.  Click for vid.   20111118133451(1) .    The snowflakes give it an animated, almost Ridley Scott kind of look.  However,  everything is exactly as the camera captured it.   Firefly sounds much quieter now that those bronze hard stops have been banished to a desk drawer somewhere.

It’s not all roses though.  From my perspective as the shooter there was a slight off-axis spiral in the tail of this bolt as it flew through the air, perhaps an inch or so out of true.     I believe I’ve figured out what is causing it and how to eliminate these occasional waggle tails once and for all.    More later.


This just in:

Last shot of the day.  Bolt weight 5,825 grains, velocity 358 fps, energy 1657 foot pounds.   It looks like that “parity” to my old Gallwey machine is starting  to disappear as Firefly’s tuning intensifies.  Also, zero waggle tail.

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