5 replies to this topic

[Jergling]

I fully owe the accomplishment of this weapon to Badger, who's idea I found when browsing old topics:

I made a burst seal gun, I got it to shoot around 40' with 4 layers of plastic bag (search "burst seal" for a full explanation) I used a bike pump and two pieces of PVC. I will post pictures soon, but I'm in a hurry right now, they may be posted tomorrow.

The pressure sorce was a foot pump, and I just smashed bag between a big and small piece of PVC.

I hope to put a better barrel on it, and then maybe a burst-shell system of sorts could be installed, and possibly a breech.

Thank you Badger



I wrote this in hurry, really sorry I can't post pics right now.

Got more time, here's some pics:


The Gun


The valve/pump connection

I makeshiftly connected the pump by wrapping layers of duct tape over the end of the tube, and sticking a basketball inflator needle through them. The adhesive made a resonable seal.

The burst seal is just crushed between pipes, if you can see that.

I got it to shoot around 15' with no burst seal, and in the open (at an upward firing angle) with 5 layers of bag, it got around 50' (That's an approximation)

Edit: added bottom section

Edited by Jergling, 11 March 2007 - 07:29 PM.

[Prometheus]

So does the bag layers burst, and the air propels the stefan? What about your next shot> How do you fire it again without losing all the pressure?

Edited by Prometheus, 11 March 2007 - 10:37 PM.

[badger]

So does the bag layers burst, and the air propels the stefan? What about your next shot> How do you fire it again without losing all the pressure?

That is exactly how the gun works. Instead of installing a trigger device to release the pressure, the burst seal breaks releasing all of the air pressure to propel the dart or stefan. To fire again, you have to install another burst seal. It isn't the most efficient design and reload time in a war is extremely too long, but it is still an effective construct.

Way to go Jergling for working with a similar concept of my design and thanks for the credit.

[Prometheus]

So it's essentially a simple, reliable design with no moving parts to fail, other that the pump, of course. Excellent homemade for younger nerfers. Congrats on your effort.

[Jergling]

The burst seal thing might actually turn out to be easy to reload, and I'm trying to create a shell/cartridge for this thing that holds the seal and has a preloaded dart in the end, It may turn out to be incredibly long though.

Btw: The barrel is half inch PVC, and I still have to cram deflated stock darts in to make them fit, while still hanging an inch out of the barrel. What size PVC should I be using? The only reason the PVC is so wrongly sized is because I'm recycling it from an old mosquito net frame (that I'll never use again).

Would shells be a good idea? or just not worth the time to make.

[King Of Butt Land]

Burst disks are a common design used on many spud guns. It is the easiest valve setup and is also the most efficient.

-Butt