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Chris,

Welcome you back!

I didn't make exact time measurments. But today, during slinging into the lake with my long thin sling I was calculating the times of flying of stones. They were a bit different: from 6 to 8 (seems even 9 seconds). These times were mainly dependent on angles of throws (how high were trajectories). Of course, quality of the used stones and each throw, were significant factors too. So, the longer time of fly, not always means the grater range.

My problem with glandes is that I usually have a limited amount of them, so I concentrate on making good throws and don't  measure the times. During one of my first tries I counted one throw at ca. 10 s. Next time I will ask somebody for measuring with a stopwatch and let you know more exact results.

Jurek

I really need to clean up that spreadsheet and migrate it to a nice sling-specific web-app. How is your Java Chris?

Not having access to it at the moment, I'd hazard that Jurek is probably slinging to around 90% of max (no drag) range already. If it was possible to reduce the drag (shape, surface trickery or higher density ammo) even further, say by half, it stands to reason that he could pick up an extra 25m or so. Slinging lead is obviously the easiest way to pick up distance, as it does tend to minimise the aerodynamic effects...

It would be very valuable validation if we could try to compile some caparative range data. We need common projectiles across a range of shape/density efficiencies. Golf balls and tennis balls are good candidates for "standards". I was thinking about maybe water filled tennis balls as well. What is important is not so much how far a given contributor can throw these, but how what the range difference is. Anyone have any ideas for a "standard" set of sling ammo that is consistent among different locations? If we stick to spheres for now, it will keep things manageable. There is going to be some pretty big spread due to different people hitting different limits with different style/physiologies, but the more data the better...

• Golf ball
• Tennis ball
• "orange" street hockey (nice and smooth)
• Baseball
• Squash ball
• Baseball
• A bucket of snooker balls would be ideal... lol

If anyone has ammo that is fully describeable we should add those off the top of my head I can think of concrete tennis balls and really pretty 1" lead spheres (hint hint)

Matthias

For sure glans orientation and throw mechanics are going to have a big impact with non-spherical ammo. As you noted in the other thread, just the spin orientation has a big effect on lighter projectiles due to the lift generated. A badly slung golfball is pretty depressing to watch as it dives into the sand rather than soaring out over the beach!

I would be quite surprised if an ovoid that leaves the sling with anything other than perfect orientation and spin will change significantly during the throw. If a spun-on-axis glans takes off pointing 40 degrees nose up (direction of throw) it is almost certain to land in the same attitude. Luckily, the benefits of lowered drag are most significant during the initial half of the flight anyway, so it doens't matter _too_ much that it ends up crosswise. This will be another argument for lower than "perfect" aspect ratios. My sim should be able to be modified to allow for changing attitude throughout the flight... if we can get it refined to the point that the difference made is outside the error I'll add it.

I used to have access to a 500 frames per second camera... what a blast it would have been to be playing with these ideas then!

Matthias

Ahh yes, to have the time to pursue such things!

A loop That is an idea. An angled loop on the trailing end that would still allow spin as it rolls out of the pouch.

Yes, and still stay in the pouch at all points during the spin.

Yes!  The centrifugal force acting on the widened grip imparts more corrective torque on the cords assuring a correct orientation at release.  This must've been how the Romans learned it!  I have had midlevel results with obloid ammo using my normal grip, with both cords eminating from between thumb and forefinger and have used a bit of fletching attatched to the bottom of the pocket via thin carbon rod to effect the same results.  This allows me to keep my the style with which I have become most accustomed, with negligible loss in speed while getting rock solid perfect spiral releases every time.  

For those who wish to try it:

http://www.nyblimp.com/superior/carbon-rods.htm

has reasonable pricing.

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Yes, yes, mgreenfield, you are right in the two points   With sidearm throw, and almost any inclination, you can also get the point first flight, but with all these styles the little problem is that you have to release just when the hand is at the level of the body and not more advanced, so that the palm point forward, and so you lose the last part of the snap, not developing the maximum momentum. But if one don´t look for max. range but penetration, the style is right.
You are the number one vertical thrower