My first Coax

[Drako155]

I am a new member here and after looking around for a couple of days I found this post http://www.spudfiles.com/forums/viewtop ... tml#282119 which was a question about a design for a coax cannon. I have made simple combustion cannons in the past but wasn't really familiar with the other types of cannons before looking through this forum. I decided that the design didn't seem to difficult after looking over the plans and drew out a simple plan for it and began my creation.

Dimensions:

2inx4ft chamber
1inx5ft barrel

I used these pipes because I had them as left overs from some other projects.


I have pressure tested it up to 140psi which is as high as my compressor will go (don't want to go much higher anyway, gauge only goes to 160psi)and I can't hear any leaks. I used thread tape on the gauge and shrader valve to get a good seal. Now all I need to do is give it some color.

I am taking suggestions for color schemes or designs because I have no idea what to do on this thing. I think for my first coax pneumatic it isn't bad.

I do need help with one thing though. I wanted to put it in GGDT but wasn't sure how to set it up. Can somebody help me with the numbers for GGDT? And I would love to test this out but I live in the suburbs and my neighbors might get mad if I start shooting things around my yard, but I'll do it anyway after I come up with some nice ammo for it.

[clemsonguy1125]

Looks ok, but is it servicible, and it looks like it has some dead space like pointed out in the original topic, as for the paint how about camo or flat black, any chance of a video

[Drako155]

I don't really plan on servicing it. If it breaks or fails I can just make another one. It wasn't expensive enough to worry about. I'm working on ammo for it now and once I come up with something I'm happy with I'll try to get a video of it in action, or at least some pictures of the damage.

[Gun Freak]

Looks ok, but is it servicible, and it looks like it has some dead space like pointed out in the original topic, as for the paint how about camo or flat black, any chance of a video

isn't it is just a ball valve cannon with the barrel inside the chamber? not a piston valve? yeah also the dead space was pointed out in the other thread, did you even read it drako? it has a negative effect, but probably not that noticeable. nice cannon. will look nice with a paint job.

[clemsonguy1125]

Like gun freak said and mrC Said does the gun have a piston, but I guess by saying coax it doesn't have to be a piston valve, just that the barrels in the chamber, how about some damage pics

[MrCrowley]

Yup, no piston valve here folks. Chamber is pretty damn huge, cut it in half but leave the barrel at the same length. Aside from that, not a bad build.

[Drako155]

Here are some damage shots and picture of the paint scheme. I was shooting at 3/4 inch MDF because that is what I had laying around. I took three consecutive shots without having to make new ammo. It didn't do as good of damage as I had hoped but I was using air compressor pressure so it was only at 120-130psi.

[youtube][/youtube][/youtube]

[clemsonguy1125]

Only 130? Dont go higher than that with pvc, nice paint scheme though.

[Technician1002]

I bet you can't wait for the next one.. Try a piston cannon. The change in power is impressive. Nice build for a first cannon. When moving to a piston you eliminate the set of 90 degree elbows in the flow path and have a much shorter path from the chamber to the barrel for much less pressure drop.

I dent car doors with marshmallows using less than 100 PSI.

[Drako155]

Tech I was thinking about a piston cannon or maybe an advanced combustion. I can't decide which I want to do because I can only fire the piston cannon near to my compressor but if I make a combustion I can transport it wherever I want and still fire it.

[clemsonguy1125]

But piston valves are more powerful, and typically cheaper

[Drako155]

But for me they have very limited mobility.

[spudtyrrant]

But for me they have very limited mobility.

If build right you can fill a piston valve with a bike pump, my 3" porting gun can be filled with a bicycle pump( although i obviously don't do it), or you could just add a small spring behind the piston. it would definitely be worth it, you would probably at least double your launchers performance.

[Drako155]

Okay, I have decided to make a piston valve coax and am making the piston driven by a smaller piston as the exhaust valve. I am near completion of it and will start a new thread for it when complete.

[Gun Freak]

wow, a dual piston valve? Awsome.