Rocket Launcher

[manakari]

This is our rocket laucher. In Alpa stage development now.

[Lilsnowman]

[Malikyte]

[Lilsnowman]

[utc_pyro]

Come on, you can do better then that!

[Malikyte]

Is that a rocket launcher or a cannon? lol

[utc_pyro]

Technically it's a ~550 fps golf ball rife with airsoft style hopup and break breach loading. It has the same muzzle energy as most .45 pistols

The point was to give him some quality benchmark to top .

Oh, and a BIG suggestion: your chamber is hopelessly too big for that barrel. Shorten it to 12" of 2" SCH40 PVC. That'll give you about 110 PSI with a 12g CO2 cartage. Currently with your effing huge one vs a 12" long on you might get 5fps with 3x the charge time with your compressor.

Also on the exit of the 2" coupler go to a 2" slip male by 1" threaded female socket and use a short 1" steel pipe nipple into the valve. You'll get better flow out of it.

Try using GGDT to model the gun:
http://www.thehalls-in-bfe.com/GGDT/

That way you can work out the best performance for whatever fixed parameters you have.

[manakari]

It is alpha stage right now. We are trying to make it shoot a miniature nerf football with fins. It has the capability to shoot a sabbot round, solid round, and what we have called a buck shot round. We shot a small bouncy ball about 200ft. It will shoot bb's out of the sabbot round approx. 80ft or so. The buckshot round will shoot bb's about 120ft with a spread of about 40ft. We are in the process of making a quick disconnect for the tank. They will be about 12in long as you said. This does not use CO2, it uses compressed air.

I will try and get a video Friday. Once it is complete I will post videos of each round being shot.

[utc_pyro]

I know you're not using C02, you have the compressor hooked up to it in the picture. I'm just saying that it's a good idea to size the gun to use co2 cartilages for refilling one tank on the field. It's a MUCH better idea then making "quick connect" tanks, and safer.

You can go down to harbor freight and get a 12V C02 to Schrader valve adapter for less then $5. If you want something more robust, a paintball 12g quick change adapter into a paintball ASA is the way to go. I actually have a launcher like that up and my parents house, and it's really the most piratical mobile fill system for applications like this.

PVC pipe has warning in it to not use in gas systems for a reason. In a water system, the pressure will drop instantly if the pipe failes due to water not being compressible. This leads to the pipe shattering, but no shrapnel travailing and direction but straight down. If you have a compressible fluid (a gas), then the pipe fails the pressure will drop at a more gradual (in milisecond time frame) propelling the broken peaces of PVC at high speed.

I've had these things blow up on me before on accident (the prototype for the one pictured did) and in staged test (detonated a "Hybrid" up in Kentucky). Both cases there was significant shrapnel, the first putting a hole in my parents house the second flung debris over 100ft.

Why is this an issue with quick-connect tanks? Well, each one of those tanks will essentially be a pipe bomb that the grander will be carrying. If that person happens to trip and fall, striking one of the tanks against a rock at significant enough force, they he'll see a real grenade.

Just something to remember, PVC doesn't not show up on x-rays!

Here is a performance simulation for what I'm suggesting using Nerf rockets:



24" long 2" PVC barrel, 12" long 2" PVC tank, filled with the equivalent volume/pressure of a 12g CO2 cartage. 450ft good enough range for you?

Great... Now you're making me want to build a new one specialized for airsoft! 42" long 3" DWV outer tube, penumatic push button trigger, proper grips, M203 aiming system, 12G system enclosed within a box on the side.....

[zbear]

[Timberwolf]

[utc_pyro]

[Timberwolf]

[zackattack]

dang that sounds like a good home defence gun .

[kosmak125]

We could test it on some cows!