SpudFiles

I was wondering if it would work to build a pneumatic gun with a flat barrel like those little disk shooting guns

Maybe, if you are going to build one what type of valve would you use.

If you shoot coins out of it, aim them at me.

They did that on mythbusters with a modified brad gun. It was to test if a penny coming of the empire sate building could kill someone.

That's an interesting idea. For a rectangular barrel you could try a rectangular piston valve. Currently I'm working on designing a semi-auto with a rectangular piston; you just need square tubing.

Or find a piece that changes your barrel into a pipe and use a conventional valve.

Take 3/4 sch 80 pipe and follow the "How-To" for rifling a barrel, but instead of turning the dowel, just make a straight line on both sides. Then a US penny will fit in the barrel flat. To fire just put wadding down the barrel and insert the penny...

Edit: Example!

MountainousDew wrote:Take 3/4 sch 80 pipe and follow the "How-To" for rifling a barrel, but instead of turning the dowel, just make a straight line on both sides. Then a US penny will fit in the barrel flat. To fire just put wadding down the barrel and insert the penny...

Why not just decide not to fire pennies while you're at it

I think it would be a pretty good idea to try a rectangular barrel simply because it would be a first.

Soon we'll be up to our elbows in Frisbee launching cannons that fire air at an angle to give them a spin...

i'm thinking about just flatening a pipe

That would work. Just use a torch to relieve the stress from the metal as you bend it, because otherwise it will break if you're not too careful.

Leave one side round and attach that to your valve and air supply.

Should be easy to calculate how much each round costs...

Solar wrote:Should be easy to calculate how much each round costs...

But if you are going to use PVC as your barrel, don't use a torch... Boil some water, keep it in there until it is mailable and bend it to your specific needs.

mikemurph wrote:i'm thinking about just flatening a pipe

Just put a flat metal bar the size of a penny inside the pvc pipe when you flatten it.

MountainousDew wrote:

Solar wrote:Should be easy to calculate how much each round costs...

But if you are going to use PVC as your barrel, don't use a torch... Boil some water, keep it in there until it is mailable and bend it to your specific needs.

He'd have to build some sort of trench over top a fire to heat up a barrel size piece of PVC.

I think you can shoot a penny from a circular barrel as well. Just get the penny in flat, and wadding behind it. It will tumble in the air anyways, so it doesnt matter if you fire it straight or not.

Just remember that flat surfaces are very weak for holding pressure. It wants to unfold itself really bad and you'll need much thicker wall than if using round tube.