Getting back into spudding - Building a copper pneumatic

[Marco321]

Hey everyone!
I missed you all lol!

I stopped spudding like 2 years ago because mom didnt think like me doing something that was technically illegal, so i had to stop. it was the when i had just finished school. Anyway, i went to Univeristy to do a degree in applied physics, after a year i found i didn't like it because the physics was too theoretical. so i changed degrees to mechanical engineering, im about to finish my first year of it, im loving it. I then found my old coaxial hiding upstairs and though to get back into it. I convinced my mom to let my do it now, so im designing my new gun.

Its going to be a copper barrel sealing piston valve, and it will be actuated by a custom made blowgun. I plan to make it a 6mm bore, and thus the air chamber will be fairly thin as a result. I plan to fabricate a sheet metal shell for it, to allow me to bolt attachments on, without fear of compromising the integrity of the working parts, as well as making it look more like a real gun.

I have rough design for it, im just working on a ammo feeding mechanism. I think it will be gravity fed, and bolt action. but im having a lot of trouble with clip design and mechanism, any thoughts would be much appreciated .

[Gippeto]

Ever had a look at the magazine and breech mechanism on a Girondini?

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[cheeseboy]

Hehe and you still live with your mum!

this is my first post in nearly a year also, now that you're a proper adult though if you get some really mean cop that finds you shooting it you can't really claim ignorance like a teen can, so be extra careful for us! with the reloading and shooting mechanism, I bought an RC tank off eBay that shot BB's and modified it heavily to trigger a QEV, but that was controlled automatic (made it remote controlled, so awesome), just throwing an Idea out there. If I hear any pneumatic gun sounds near where I live, I'll know its you!

[Marco321]

Wow thanks Gippeto!, that will fit my gun design very well! Im going to look into that!

Haha living with the rents is great, free food and so on

EDIT:
I think i see a potential way to make that mechanism into a pump action sort of thing.

EDITEDIT:
Where would i find a spring to push the ammo down? Anyone know any good websites?

[Gippeto]

Welcome.

I'm not sure about the "land down under", but you might try here;

http://www.centuryspring.com/

[Technician1002]

If they are not legal there, simply make a scientific apparatus and only operate it in a lab or field test site, not somewhere exposed to the public.

For example look at the thread on the golf ball launch challenge. If weather holds up, I may go and test launching golfballs 50 yards and see if I can land them in a 5 gallon plastic bucket. I'll bring a copy of the rules with me when testing. It is how I range tested the t shirt cannon in a city park. I set up signs, measured out distances, launched shirts for distance and kept a pressure distance chart up to date like a score board.

In the public is not a place to blast everything in sight.

At a radio amateur campout field day, I brought the "Antenna" launcher and was tossing tennis balls and bottles of water trailing string. The sherif showed up to check fishing licenses. I approached him and let him know of our activities and asked if it was any problem and offered to put it away if it was.

Nice guy, he took the opportunity to practice search and rescue and offered to find tennis balls we lobbed into the resivour. We range tested the tennis ball launcher at full power into the lake and he retrieved the balls. Only one full of water for distance wasn't found. It may have sank.

Some of your testing needs to be presented properly. Dangerous blasting everything in sight will most likely get you in trouble.

[Marco321]

Lol i may like spudding, but im not silly with it . I personally prefer the challenge of the design and build over shooting it . But shooting it is still fun, but yeah, i only do it on my own private property, out of sight of the public, with proper backings. Plus ill be shooting stuff with a diamter of like 6-8mm, so its not that big. My main worry is the bang that is associated with each shot lol.

EDIT: Thanks for the link

I might look in hobby stores for small springs

[absinthe]

if your in oz then try the big green shed (bunnings) they have a good range of springs that might work with a few mods to the design

[Marco321]

thanks absinthe