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Posted: Wed Jun 20, 2007 6:10 pm
by Velocity
schismatized: Could you provide a link to the place where someone claimed to have gotten 1400 feet with a concrete filled tennis ball?

Posted: Wed Jun 20, 2007 6:49 pm
by schismatized
yeah let me find it again.

EDIT: here you go. http://www.spudfiles.com/spudtech_archi ... t=distance

Posted: Wed Jun 20, 2007 7:41 pm
by VH_man
They siad they fired it off a hill. that makes a big difference................

i know that with marbles i can get 100 feet easily, but my range is 100 feet long................

i know that darts fly REALLY well. i remember firing a cheapy magnetic dart out of my cannon and watching it fly for almost 15 seconds...................

if youre going for distance go for heavy projectiles that have a very low drag cooeficient, like an arrow for example............

Posted: Wed Jun 20, 2007 8:12 pm
by potatoflinger
With my new paintball sniper rifle, I can get over 1,000 feet, so I would say that with the right cannon, you could shoot a tennis ball that far.

Posted: Wed Jun 20, 2007 8:35 pm
by sjog
google earth for distance----- shoot into a pond/lake

when I changed to GB's I could not belive the added distance over spuds
GB's are free to pick up in the off season. I got 60-80 at a time

Posted: Wed Jun 20, 2007 9:18 pm
by jrrdw
I have yet to shoot a spud, i'm not joking. Isn't that sad?

Posted: Wed Jun 20, 2007 10:07 pm
by clide
jrrdw wrote:I have yet to shoot a spud, i'm not joking. Isn't that sad?
Nah, I haven't shot them out of any of my guns either. I shot them once out of somebody else's gun before I got into the hobby, but not since then.

Posted: Wed Jun 20, 2007 10:32 pm
by schismatized
^^^wow that is disgraceful haha. i wonder if those pool torpedoes would go far? i think the best bet is to cast your own lead bullets. then you could make them super drag resistant. :twisted:

Posted: Wed Jun 20, 2007 10:55 pm
by Flying_Salt
My distance is really low, since I have to pump up 5 feet of 3'' pipe with a bike pump. At 60 psi I shot a golf ball 650-700 feet. (My cannon has so much dead space its not funny)

Posted: Wed Jun 20, 2007 11:19 pm
by Modderxtrordanare
schismatized wrote:^^^wow that is disgraceful haha. i wonder if those pool torpedoes would go far? i think the best bet is to cast your own lead bullets. then you could make them super drag resistant. :twisted:
Lube up a barrel for one of them really good, and put a thin burst disk in between the ammo and the valve so no water gets in the chamber/valve. Fire away when underwater.

Posted: Thu Jun 21, 2007 9:11 am
by joannaardway
schismatized wrote:joanna, could i see your distance calculator?
Here you go - a link to the spudtech archive thread:
http://www.spudfiles.com/spudtech_archi ... calculator

I know I've said it before, but the V3.0 beta is almost done now. It should be out soon... I hope.

Posted: Thu Jun 21, 2007 12:34 pm
by schismatized
everytime i download that file it comes up as corrupt :evil: could you possibly reupload it?

Posted: Thu Jun 21, 2007 1:13 pm
by jimmy101
joannaardway

Does the new version fix the significant problems with the vertical components?

I tried to use version 2.2 to calculate terminal velocities of golfballs and it looked like it was giving a V<sub>terminal</sub> that was perhaps 10 times greater than it should be.

I just gave it a launch angle of 90, an initial height of 1000m, a high muzzle velocity (1000m/s, doesn't matter if the model has problems near the speed of sound, it should have zero affect on the terminal velocity result), the Cd, mass and diameter of a golfball. A graph of vertical velocity (calculated from deltaHeight/detlaTime) versus time should go asymtotic to the terminal velocity of the projectile.

Terminal velocity of a golfball is about 40 m/s (132 fps).

Posted: Thu Jun 21, 2007 3:13 pm
by joannaardway
jimmy101 wrote:Does the new version fix the significant problems with the vertical components?
That's the main thing it solves. Before, the drag wasn't applied at that point, but that has now been sorted.
The terminal velocities are now pretty much dead on target.

The other main thing that has been sorted include improved atmospheric controls to cover pressure and temperature effects on drag.

Many of the old boxes that confused people have been removed, simplifying the thing to the level where people should be happy with the use of all the boxes.
The new version will require macros to run properly, which may not be to some people's tastes, but it does hugely reduce the file size (and download time), and also the calculation times.

@schismatized: I've just checked the file. It seems perfectly intact to me.

Posted: Thu Jun 21, 2007 3:55 pm
by schismatized
Image

after i click ok, excel just freezes.