Golf Ball Cannon - Design Specs

March 29, 2006 | Vanity

[gondramB]

"Usually the last words uttered by some poor sap.But fun while it lasted."

That sounds the story (or urban legend, I'm not sure) of the drunk guy showing off by swinging his chain saw around when he cut his head off.

[Donald Meaker]

Drag is reduced by about 2/3rds by the dimples. Amazingly, the fellow who figured out the dimple scheme had no instrument more sophisticated than holding golf balls in his fingers while blowing cigar smoke over it.

One problem is that one side will drag, and cause the ball to spin in a non-axial way. Then the ball will sail like a badly shanked 9 iron shot.

Of course if one uses a rifled tube, that will prevent it, but also will greatly increase pressure required and the barrel friction.

[Donald Meaker]

If you really want to get some oomph, put in the propane mixed with oxygen, and add a spark generator.

We used to shoot potatoes that way.

[Jaysun]

I wonder how he's going to keep the "bullets" in place until time to fire. Also, why not air or CO2 with a regulator/safety valve?

Here's a link to plans for an "air cannon", maybe he'll find it useful.
http://www.corin.com/bill/paintball/aircannon/

[steve8714]

ask this question first; what are the lower and upper explosive limits of propane?
how about CO2?

[gondramB]

"Drag is reduced by about 2/3rds by the dimples. Amazingly, the fellow who figured out the dimple scheme had no instrument more sophisticated than holding golf balls in his fingers while blowing cigar smoke over it."

And sadly, that's what I'd have to do too...

As for rifling, it doesn't work as well with spherical objects since the rotation from rifling has a stabilising effect only when the axis of rotation was in the direction of motion.

And in any case I can't calculate the effect. :)

[NormsRevenge]

Hold the propane..

Big Bertha is on the links.

[MindBender26]

There is some serious technical help available for your project.

Each fall at pumpkin harvest time, the semi-sober citizens of "Slower Lower Delaware" hold a tournament to see how far teams can shoot pumpkins by compressed air power alone. The record is more than 4400 feet, more than 3/4 of a mile downrange, in the air!

See their website http://www.punkinchunkin.com/ for some people to call.

This is NOT a joke.

[MindBender26]

For compressed gas, (non explosive), helium works best, because being lighter than air, it has less inertia and moves more quickly.

The high-end inflatable emergency floats on helicopters all use compressed helium

[Sauce]

Yeah, that looks good. :-)

[MindBender26]

Check out PB040070.jpg on the day one pictures. It appears that they are adding air from additional sources as pumpkin is moving up barrel.

Much like a cannon Germans has late in WWII that had multiple powder chambers alongside barrel.

[Pontiac]

As for rifling, it doesn't work as well with spherical objects since the rotation from rifling has a stabilising effect only when the axis of rotation was in the direction of motion.

Maybe he could consider a rifled sabot as is used in shotguns.

This would also help in limiting gas leakage by the ball.

[gondramB]

Good idea - that would also help withh the diameter issue.

[Ursus arctos horribilis]

Uh, a length of DOM hydraulic tubing drilled for a fuse and breeched on one end, with 300 grains of 2F will give a patched golf ball say around, oh, 12-1300 fps. Love the smell of holy black going off in the morning.

[Ursus arctos horribilis]

My, my, look what I googled up, looks like he won't have to build, he can buy one.


http://www.diamondbackcannons.com/

Or, I guess he can buy several if he wants.

http://www.google.com/search?hl=en&lr=&q=black+powder+golf+ball+cannon

[sully777]

THIS LOOKS LIKE A JOB FOR...



These guys love to build weapons such as the one from the thread topic.

[SWAMPSNIPER]

[crowman]

He should try a SPUD GUN instead, they're fun...

[Loud Mime]

What is the air speed velocity of an unladen swallow?

[gondramB]

About 10 m/s apparently :)

http://www.style.org/unladenswallow/