Initial construction

[Tony.Knaak]

Greetings, spudders.

I just finished my initial construction on my second pneumatic cannon. I test fired it approximately 30 times to make sure there were no leaks and it would perform decently. I took a few photographs and video clips of the test. I have to add some more aesthetics and paint to finish it.

Gun Specifications:
1" barrel, 38" long
2" chamber, 8" long
1" heavily modified RainBird sprinkler valve
20oz. CO2 supply
Kobalt belt mounted pressure regulator, unmodified
Breech loading

Here some photographs:









And the video:

[youtube][/youtube]

So the "Toypedo" was a fail as ammo. It is too small and the paper towel wadding didn't really work.

I need to do some research on how to modify the pressure regulator to up my max psi.

Anyone have suggestions on some better ammunition to use for a 1" barrel?

[jook13]

Well, That looks like a fun one to shoot! I bet the convienence of co2 portability is awesome. I had a barrel made out of 1 inch schedule 40 and I found some big marbles that fit nicely in it. May be worth looking into.

Have fun and dont hit them neighbors across the river or lake or whatever.

[jackssmirkingrevenge]

Nice to see such a compact setup. With some work you could incorporate the Kobalt unit as part of the stock to have it all on the launcher, and with a 3/4" barrel for marbles feeding from a simple tee breech you could make yourself a semi-auto.

[Technician1002]

Greetings, spudders.

I just finished my initial construction on my second pneumatic cannon. I test fired it approximately 30 times to make sure there were no leaks and it would perform decently. I took a few photographs and video clips of the test. I have to add some more aesthetics and paint to finish it.

So the "Toypedo" was a fail as ammo. It is too small and the paper towel wadding didn't really work.

I need to do some research on how to modify the pressure regulator to up my max psi.

Anyone have suggestions on some better ammunition to use for a 1" barrel?

Very nice job. As far as ammo, there is a sticky on just that subject. Enjoy. Lots of great suggestions.

http://www.spudfiles.com/forums/ammo-ideas-t1724.html

Gumballs is my favorite.

[starman]

Great portable pneumatic design! I like the breach loading feature.

Get some 1" wooden dowel rod and sand down some ammo. Also C Cell batteries work well.

[mister pointy]

wow, i made a 1'' breech loading barrel that looks almost identical to yours that i eventually incorporated into a sniper design.

I also have the exact same co2 setup, gotta love the portability

anyways, great gun!

[Tony.Knaak]

Well, That looks like a fun one to shoot! I bet the convienence of co2 portability is awesome.

I had a blast shooting it for the first time! The CO2 fills up the chamber in about 2 seconds as apposed to 5 minutes with my bike pump on my first one. Less down time and more shooting!

Nice to see such a compact setup. With some work you could incorporate the Kobalt unit as part of the stock to have it all on the launcher, and with a 3/4" barrel for marbles feeding from a simple tee breech you could make yourself a semi-auto.

I have been brainstorming on my next cannon with similar ideas. I am just taking it one step at a time construction wise. I figured I would start simple with PVC and later progress to metals, higher pressures, and auto feeding.

Very nice job. As far as ammo, there is a sticky on just that subject. Enjoy. Lots of great suggestions.

Thanks, still new on here, haven't really explored the forums that much.

Get some 1" wooden dowel rod and sand down some ammo. Also C Cell batteries work well.

Sounds devilishly destructive! I'll give it a go.

wow, i made a 1'' breech loading barrel that looks almost identical to yours that i eventually incorporated into a sniper design.

I stole the design from a sticky post on here somewhere.

Thank you all for the comments!

[Tony.Knaak]

Hello again two years later...

I kind of put this gun in the hall closet and forgot about it. Other hobbies took over (paintball, disc golf and that curse called WoW). But I resurrected it a few months back and started tinkering with it again.

<a href="" title="gun_case by tony.knaak, on Flickr"><img src="http://farm6.static.flickr.com/5144/568 ... 1da4_z.jpg" width="640" height="427" alt="gun_case"></a>

I purchased a a nice padded gun case for it, I was getting nervous that I might break it!

<a href="" title="handle_close by tony.knaak, on Flickr"><img src="http://farm6.static.flickr.com/5148/568 ... 247c_z.jpg" width="640" height="427" alt="handle_close"></a>

You can barely see what is left of the sprinkler valve. I molded lots of JB Quik around it, and sanded it down nice a smooth to a shape that I like. The steel plate on the bottom is tapped with 1/4" 20 holes and mounted to that are two 1" electrical conduit brackets (aka "mini's) that were secured to the valve to add stability. The plate also had a hole in the middle for the trigger air dump. Using the same 1/4" 20 bolts, drilled and tapped two metal blocks and threaded them on to act as handle mounting brackets. You can see the two allen head bolts on the oak handle. And yes it is bedazzled. I am super gluing rhinestones on it to look like rivets after it is painted.

<a href="" title="handle_close2 by tony.knaak, on Flickr"><img src="http://farm6.static.flickr.com/5028/568 ... 87c9_z.jpg" width="600" height="567" alt="handle_close2"></a>

Another close up shot. The maroon material is bondo (the auto body sanding filler) to help smooth it out even more. The poplar rail on the top is just a mounting base for more details to come. I plan to mold it out with more JB Quik and add some detailing / dials / gauges / lights. I am trying to replicate a Dr. Grordbort's (http://www.drgrordborts.com/) style gun.

<a href="" title="handle_bottom by tony.knaak, on Flickr"><img src="http://farm6.static.flickr.com/5186/568 ... 7b80_z.jpg" width="640" height="427" alt="handle_bottom"></a>

From the bottom you can clearly see the air dump trigger and the routed handle.

More update pictures to come, hopefully not two years apart!

[wyz2285]

Nice I like it! and the bag too

[Gun Freak]

You have a DWV endcap into which you tapped a single layer! bahaha. You could easily swap it out for a pressure rated one. I like it... would look really good with paint but it is still cool.

[Slyder2k8]

Nice job. I love the portable idea. gotta look into getting me one of the Kobalt set ups from lowes. Only suggestion i would make is instead of such a modded valve maybe you can build a piston design. I'm new to the forums as well but have seen allot of posts on the piston designs. check em out.

[whoa044]

That gun looks pretty awesome! Nice, simple, and effective design.

But there quite a few disadvantages that you should know about using CO2, although you may already know them:
1: Because it's so dense, it isn't "fast to move" in the air chamber, and performance will be hindered
2: When CO2 evaporatoes, it chills (as you know), and after using it several times in a short amount of time the chamber will become brtittle, and may crack. The cold air may even reach the sprinkler valve and ruin it's diaphragm.

I would recommend an HPA tank. The cheap ones cost $50 (maybe less), and afaik, will last much longer than a CO2 tank of the same size.

[jackssmirkingrevenge]

Well done on the aesthetics, looking forward to seeing it painted

[Technician1002]

But there quite a few disadvantages that you should know about using CO2, although you may already know them:

Now be fair and list the advantages too.

1. The denser gas has less blow by past the projectile. This is good for heavy projectiles with a poor barrel seal.

Where Helium would blow quickly past a heavy loose fitting projectile, the CO2 would drag it along.

[Meat]

Whoa, HPA is going to be more consistent especially with temp. changes, but
c02 has advantages as well.. For example, not everyone has a way of filling up HPA tanks, but you can go to sporting goods stores to get co2 fills really easily. I know he said he played paintball, so that shouldn't be a problem, but for others (like me) the nearest field is about 1 1/2 hrs away.


HPA is good though, because the more expensive ones can be larger (70 cubic inches) and hold more pressure (4500 psi, opposed to the $50 tanks 3500 psi)




I forgot to ask, how many shots do you get off one tank?