Little Walloper (that heavy 9,000 grain bolt made yesterday),  gets kicked out of Firefly at a fairly sedate 200 feet per second.  Click for video:     20111010120415(2)

Something must have changed between shot # 12 and shot #13.  Overall projectile energy is down to 796 foot pounds from 1300 odd foot pounds when we were shooting that 7,000 grain bolt.  I suspect the bowstring has loosened due to some slippage in the eye splices.   They really need to be cross stitched.  None of this can progress until I break down and order some more double braid for bowstrings.  Mr. Pat B has offered these insights into how imperative it is to have a tight string.

“If you remember the figures I  posted back when I first found your blog, they show that the velocity
ratio of missile-to-arm-tip doesn’t even hit double figures until the
last couple of degrees of movement. Then it shoots up exponentially.
The difference between inswingers and outswingers is that tiny
time-slice. The outswinger wins the contest for 99% of the draw length.
The inswinger relies on its performance over the remaining 1% to turn the
advantage the other way. But that dramatic turnaround depends on a
bowstring capable of tautening to the max. At the moment its slackness
is losing you a lot of velocity, and all readings would be thrown out
of kilter.”

I couldn’t agree more with his analysis.  You can still sense from the sound of her firing that Firefly is not actually breaking out in song yet.   Strumming the string yields no tone.

On another note:    I need to remount the electric winch.  The hand winch would scale much better if there was a selection of stout legionaries for the task ,  but as can be imagined,  these heavy draw weights get a bit much for his Lordship at times.  Click for vid.   20111010120415(3) .      And this is just part of what it takes to get it up to 3400 lbs.   This particular shot ended up at 4200 lbs of draw weight.  Talk about Pilgrims Progress.

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