SpudFiles

)DEMON( wrote:The only thing I would really want to launch 300 yards is my sister..

With a goodly sized hybrid it can be done.

I'd recommend you to PM D_Hall for that. For a few tenthousand bucks he surely can arrange that for you.

Well I am looking for simplicity and I have never got a piston to work. I am thinking about using small pvc rockets.

You can probable get those out to 300 yards without too much trouble, although I would suggest a GB gun because the ammunition is cheaper (Recently bought 300 balls for less than 15 cents per, and you could probably find them cheaper than that) and they are good for distance shooting. Oh and yes, you can actually see the ammunition that far away, A tennis ball isn't too hard to spot depending on the backdrop, but a GB might a little more difficult.

You could always try using colored golf balls, the ones that are neon colored and stuff. Not sure where to get them though.

Some of my results, for what its worth for guessing at your hypothetical gun's performance:
1" Pneumatic, 54" Chamber and Barrel, Blowgun-piloted sprinkler valve
30 degree angle, firing 75 gram bullet made out of C battery and tail fins to rotate it
50 psi
122m range (=133.42 yds)

So a pneumatic would have to be on order of magnitude more powerful than my example to achieve double the range and more

When I shoot golfballs hard enough [burst disk and longer barrel] to get out beyond 300 yds., they are so fast as to be almost invisable..even colored ones... .. and lost very quickly in the clouds and sky. That's really their problem..they have great range and speed...so much so there's nothing to see...and good luck finding them. Tennis balls, softballs, baseballs won't have the same monster range but you'll at least be able to watch them travel in flight and land.

jimmy101 wrote:Most claims of 300 yard ranges are bogus. It is possible with a golfball but probably not possible with most other common ammos (tennis balls, spuds etc.).

Can you even see a 1.5" shell at 300 yards? I have trouble seeing a 2" spud at 100 yards, at 300 yards the shell appears 9x smaller than at 100 yards.

I don't fall under the bogus claim category.

I measured my softball shot to the foot with a GPS which has an error factor of +/- 7 feet. Also just measured a lacrosse ball launch 1013 feet.

Softball with a 32" barrel and the lacrosse ball with a 36" barrel.

Good luck trying to get a potato to go 300yds. I cant do it with my setup. If I was looking to get 300yds from a cannon, I would recommend a solid ball (softball, baseball, lacrosse ball, golf ball, etc)

I like the 4" x 12" combustion chamber setup.

Jeff

I have done it myself from HEAL. I did the quick and easy "tracer" method once, and covered a tater in glo-stick fluid. Fired it into a nearby field late one evening, which gave a cool trail through the air (normally, my spuds are too small and fast to see).

Then went out after it counting my paces. I have a very convenient 36 inch pace (to within a couple of percent in fact, which makes it more accurate than some brands of laser range measurer, as long as I walk in as straight line).

Got to 381 when I reached the remains of the spud smeared across the floor, so it is possible, although a 300 psi piston valve cannon is a bit more than most people claim to have done it with.

When you're shooting for distance, factors such as air resistance really come into play. A golf ball for example is a relatively terrible aerodynamic shape with relatively poor sectional density. I say "relatively" when compared to a saboted dart which can be constructed in such a manner to be lighter (including sabot) than a golf ball, but with higher sectional density by virtue of its small cross-sectional area.

This means it will accelerate to a higher velocity from the same launcher, and keep that velocity for longer. Such projectiles are a bother to make in bulk, but if you're aiming for a personal record I say it's worth the effort.

You can even buy ready made darts so all you have to worry about is the sabot

Do you think those will fit in .5 or .75 inch pipe?

If I remember well they should fit in 0.75" pipe, if not you just have to trim down the fins a little.

It's not to hard to make your ammo from scratch either.

Yeah I have made all sorts of different types of darts using what ever I can find.

Pneumatic! And use GGDT for the pneumatic if you're not sure yet.

the way i keep track of my golfballs is by attaching a colored tail from plastic ribbon with a small wood screw.
wow Jeff 1013 feet!

n-strike wrote:Pneumatic! And use GGDT for the pneumatic if you're not sure yet.

Either you mean HGDT, which I think is only for combustions, or there's a pneumatic program I don't know about! If it's the latte, please give me a link to this "GGDT".

edit: wow!! there is a ggdt!!!