I'm good for just about 50m/s in current trim, which works out to 112 mph. This is measured in various not particularily accurate ways that all support the value. From looking at ranges that people post, I'd say that most of the "medium" slingers here are in the low forties-50 range. Once you get into the mid 50s (m/s again), there is a transition in the type of flow over the glans in flight, and the drag on the projectile goes way down - getting over that "hump" is something to work on!

The density of the projectile should make no difference to the initial speed of the throw. The reason lead goes further is that is slows down less quickly once it is in flight.

Google will do conversions if you type in "50 m/s in mph" for example.

I really need to get back to my simulator project, and the ballistic pendulum, and Techstuf's new "sonic" speed measurement technique... We were making good progress there for a while, but have gotten distracted (and lost Hondero...)

Matthias

Johnny, Matthias,......will try and get Chrono figures and time of flight data for interesting 'pocket velocity' and averaged velocity over distance, for some 'hopefully' revealing velocity/drag ratios for various ammo types.

Got a big old water tower at the edge of town....I'll try and post my 111th take or so.....when I actually succeed in hitting it from 300ft.....(buddum bum, joke, people)

It'll probably only take 50 or so....


Should be no problem getting an average velocity stat accurate within 12% or so, via this method.  Others who may wish to try this method should obtain better accuracy using a 'referee' to time the flight via sound alone (blindfold him first).....perhaps affixing one of those small 'snappers'/'poppers' (which are thrown down on the ground and emit a report upon impact) above the ammo on the release side of the pocket, will prove more accurate.....as the time of the report upon release as the ammo comes into contact with it at release will be quite near the moment of actual launch.

We'll see.

Also flirting dangerously with the prospect of marketing two radical sling designs.....'R'.....one of which elevates the velocity/accuracy obtainable with a solely human powered sling by an order of magnitude.  The other has multiple advantages, including the inherent optimization and physical alteration of ammo at the moment of release....stealing only a tiny portion of momentum to acquire great advantage.


TS

8)


I am certainly interested in the disparity between averaged velocity via time of flight reckoning and Chrono measurement of 'pocket velocity' (muzzle velocity)

Cute Java applet:

http://www.grc.nasa.gov/WWW/K-12/airplane/sound.html

Take a look at the tiny variable in speed between your altitude/location and sea level.

Johnny,

The m/s is velocty unit in the metric meausrement system SI.
m - meter
s - second

m/s = metres per second.

Great suggestion, Yurek.....another easy and interesting exercise to compare to Chronograph.


8) 8)


TS

This may be alittle off topic, but has anyone ever done a good comparison of power between a bow and a sling?
My bow might send a 550 grain arrow around 180 feet per second. I don't know the exact fps, but let us say 180 fps for the moment. While a good slinger might send a 3-4 ounce stone within 10-20 fps of the arrow's speed. If 1 ounce equals 437 grains, then a 4 ounce stone is the equivalent of shooting a 1,748 grain arrow at near bow speeds. The sling is incredibly powerful, it's one major drawback being that it relies on crushing force to do it's damage as opposed to the hemmoraging caused by an arrow.

razors for fletching? ouch.

Wow.  Interesting......I had heard of Drake's performance, yet was never aware of his unique setup, nor of his friend who introduced him to the sport!

The fletching is quite similar to that on the darts I have seen.


Thanks for the info!


TS

8)