Well I agree with the theory you presented to back up your claim. Just find the claim astonishing and hard to believe.
Love to see a video.

from what i know yurek used elongated projectile(50g), bipointed which is more aerodynamic than a sphere and thus needs less speed (for vacuum 71m/s) so he probably threw 71-85m/s and that is only if he didn't mess with angle of attack.

you are saying 77g at 100m/s.

Apex-apoc wrote on Aug 14^th, 2017 at 5:47am:


i can't believe the answer hides in just more throws, and then the sling does all the work.
are you talking about specific training  year in year out and having a peak one time per year like olympic throwers? or you can perform consistently( with small deviations) throughout the year without risking major injuries in your arm?

personal records:
200m 90cm sling(old), http://slinging.org/forum/YaBB.pl?num=1474293154/new, measured with camera frames  57m/s 72cm sling 50g stones .
a spotter would be very helpful...

in 2017 (till today) performed 9261 throws, of course most of them are accuracy and form training, if it was for speed i'm afraid i would have serious shoulder problems.

I say the same as she Mersa: I'd love to see you when you're slinging! Could you make a video? If you do not want to show at your face, put the balaclava on the head 
The finest thing would be to see a slow motion film like David Morningstar.

[quote author=4961767765040 link=1499008756/64#64 date=1502665097]I think in theoretical terms things can potentially travel further in air than in a vacuum(with gravity as a constant). If perfect spin and angle are achieved and lift is generated. Real life might be harder to replicate.
I've slung lead and it's not easy to find, even painted bright colours. You may be on some very compacted soil but for me it's buried deeper than 3 cm. I also don't sling anywhere near the speeds your talking.
Who knows if your telling the truth, enjoyable reading none the less.[/quote]

There's no doubt that heavy backspin extends range for mid-weight things like stones and golfballs. I'm not sure how much effect it might have with solid (polished?) metal spheres. Probably rather little - and Apex-apoc seems keen to avoid wasting initial kinetic energy going into spin.

Quote:


I skipped most of the earlier posts but yes you are right.

Projectile motion with drag is very complex and analytic solutions for distance are not even possible. It can only be calculated computationally or approximated.

The statement that drag is inversely proportional to range (even just approximately) is not rigorous and needs mathematical justification.

WojtekimbieR wrote on Aug 15^th, 2017 at 11:35am:


What "method"? Drag depends 1 : 1 in cross-section of bodys moved in fluids / gases (unless the bodys are of a more or less aerodynamic shapes like rockets, UFOs or dolphins).

The diameter of a sphere / ball of tungsten (weight 100 g) is half of "diameter" of a ball of stone (with the same weight). So the cross-section of a sphere / ball of tungsten is only a QUARTER (25%) of cross-section of the stone (with the same weight or mass). So it would be to expect that its range even were the forthfold.

But this "second halving" of the tungstens drag gets a "compression" (termination) as a result of its higher range (that is similar to a longer flight time - dont know how to explain better or with all details in english).

Maybe in a physical absolutely correct calculation this had be to calculate more complex for more accuracy ... but anyway: PLEASE (!) go to this side http://www.schuetzenverein-ettenheim.de/sportschiessen/ballistikrechner.php and try it:

Insert a sphere with weight of 100 g while diameter is 60 mm ... choose a speed of 100 m/s and let the tool calculalte what the shooting-distance is.

Then try the same once more, but this time with diameter 30 mm (also 100 g) and look what range will be the result after calculation.

DO IT !!! (... and you will see it will be nearly the twice of range of the sphere with diameter 60 mm!). 

And PLEASE - english is not my mother tounge - do not expect an complex / abstract explanation of math in mathematically expressions from me, because these expressions to me are not only "mathematically", but "foreign language" too in the same time. Partially this would be english "slang", respectively "professional chinese" I never heard and never read.

Do you want to ask your questions in german?
Und darf ich dann auf Mathematisch-Deutsch antworten???


... so "YES", my so-called "relative drags" in my small table are approximations only. But what do you want? Do you want to throw rocks as far as possible, or do you want to calculate an orbital flight way to saturn and to celebrate "science" there?

Apex-apoc wrote on Aug 15^th, 2017 at 2:53pm:


i prefer an answer in german than none at all....

wanderer wrote on Aug 15^th, 2017 at 6:57am:


i don't understand how heavy mass (sun) relates to hand and sling , how is the keplers 2nd law applied in slinging?
the only thing that seems similar is geometry
if you have understood please explain

@WojtekimbieR,JudoP
you seem to agree with the approximation i made , that's a minimum speed, Apex-apoc claims 100m/s (!!) .The problem that concerns me the most is not external ballistics  but the internal ballistics(of slinging) that throw something 77g heavy at 100m/s (or even 80m/s)

Apex-apoc wrote on Aug 15^th, 2017 at 3:54pm:


different forces are applied in different manners and angles, in theory an arm might perform what you are saying, but in reality an arm has many limitations.
with the 2nd law of keppler  the max velocity of a planet is when it is closer to the sun, how do you tranfer that to hand and sling?

Apex-apoc wrote on Aug 15^th, 2017 at 3:54pm:


i don't understand what you are trying to say. if you can't write it in english rewrite it in german