pumpkin chuckin competition

[pyromanic13]

anyone gonna be in Delaware for the comp?

I live in CT but I gonna try to get some friends together and take a train down there..

[Lentamentalisk]

God I want to go, but that is really far to go from California...
Woosh! Splat! Yay!

[benstern]

Spudgunners are a different breed from pumpkin chunkers.

We like power - They won't allow hybrids, only pneumatics
We like plastic - they like all metal
we like science - they don't really like factual data

[Lentamentalisk]

We like plastic - they like all metal

They are using insanely high pressures. Nobody in their right mind would use plastic on such pressures.

[jrrdw]

Spudgunners are a different breed from pumpkin chunkers.

We like power - They won't allow hybrids, only pneumatics
We like plastic - they like all metal
we like science - they don't really like factual data

Hahahahahaha -- I just woke up the rest of the house!

[Fnord]

(Hey, I like all metal too...)

Actually, most of the pneumatic guns they have don't go past 140 psi.
The reason for this is pumpkins aren't very tolerant of high g-forces (pie).

It's also not surpising that you'll never see a hybrid pumpkin cannon around:
-Flames are not allowed
-A hybrid chamber that size is a huge safety hazard
-mashed pumpkins

[jrrdw]

(Hey, I like all metal too...)

Actually, most of the pneumatic guns they have don't go past 140 psi.
The reason for this is pumpkins aren't very tolerant of high g-forces (pie).

It's also not surpising that you'll never see a hybrid pumpkin cannon around:
-Flames are not allowed
-A hybrid chamber that size is a huge safety hazard
-mashed pumpkins

The main chambers are massive, thats why they can shoot a pumkin a mile.

[benstern]

They don't like plastic ONLY because the pipe makers don't want it used for compressed gases. That decision is based on legal worries more than scientific data and the chunkers can't possibly see past that. They also have not to my knowledge ever used a high preformance valve on a chunker. Mostly only pneumatically or electronically actuated butterfly valves.

[trae08]

Actually, most of the pneumatic guns they have don't go past 140 psi.
The reason for this is pumpkins aren't very tolerant of high g-forces (pie).

hes right its the fact that they have such a large valume of air that pushes the pumpkin the distance. not the pressure they go to.


mythbusters shot a "a 24-lb, cast-iron, Civil War Cannon ball " around the distance of a mile with only about 60 psi of steam if i remember right. but they had a pretty large volume of air behind the ball.

(mighta been half a mile)

[benstern]

Plus why pumpkins? I would think that bowling balls would be superior.

[ALIHISGREAT]

Plus why pumpkins? I would think that bowling balls would be superior.

thats like saying "why spuds?" itsw because people like to shoot vegetables, also i would have thought they were cheaper.

[DYI]

I would argue that pumpkin chuckers are not really a different breed than spudgunners, they only pursue their hobby on a different scale.

In some of the smaller chunkin' comps, there are very ingenious designs that wouldn't normally be allowed at the larger, international competitions.

I consider myself a spudgunner, and I have rarely ever used plastic for anything other than barrels, because I aim for performance, and have a healthy fear of PVC pipe filled with pressurised air. If you look at the archives of spudtech and spudfiles over the years, it would appear that metal launchers are becoming more common all the time.

I would assume that the reason pumpkin guns don't use 10" porting piston valves is due to the fragile nature of the pumpkin, which is also the reason that they don't use crazy high pressures. In the long term, the project that I am currently working on would have about 1/4 the muzzle energy of an internationally competitive pumpkin gun; is it a pumpkin gun? Are the SWAT or FEAR potato guns? Where is the line?

Pneumatics can be just as powerful, or more so than hybrids. There may be a limit to the maximum pressure that you can achieve with a hybrid (think slower combustion at super high mixes+ heat loss), and they also pose a DDT hazard.

The only things that I dislike about punkin' chunkin' are: a) the rule banning use of gases other than air

and b) they're not powerful enough

[clide]

They don't like plastic ONLY because the pipe makers don't want it used for compressed gases. That decision is based on legal worries more than scientific data and the chunkers can't possibly see past that. They also have not to my knowledge ever used a high preformance valve on a chunker. Mostly only pneumatically or electronically actuated butterfly valves.

And the fact that they have had PVC shatter at their competitions. Nobody in their right mind would want 100 feet of PVC pipe turn into shrapnel around a large crowd.

I don't think it is that spud gunners like PVC (I don't) it's just that it is cheap, adaptable, easily available, and easy to work with.

There has been one pumpkin chunker that used 4 commercially made piston valves. It was called the "Big Blaster" (so is the valve). It can be seen near the bottom of this page: http://www.siege-engine.com/PunkinChunk2000.shtml

[spudgunnerwryyyyy]

I completely agree that spudgunners are a different breed than those people. Mostly the main factor is budget. We use engineering skills to get the most out of our small teenage budget through things like piston valves. Most of there cannons are just bolted together with no special fabrication.

[DYI]

One has to understand that, due to the fragile nature of the pumpkins, and the ever constricting rules in the large competitions, there is very little room left for creativity in competitive punkin' chunkin'.

If there were less rules, I'm sure that people like us could actually be competitive, or victorious at larger competitions, but, as is, the only way to achieve longer range is to throw more money at the launchers. Kind of sad, when you think about it.

I did see that video of a PVC barrel shattering at a comp though, scary stuff.