SpudFiles

Okay so this is the first gun i have posted, although not the first made. It is a coaxial piston cannon. It is the first working piston cannon i have created and I LOVE this thing.

Specs

Overall- 52 inches

Chamber- 16 inches of 1 1/4 inch pvc

Barrel- 35.5 inches of 1/2 inch sdr 21

Exhaust- 1/4 inch QEV piloted by a pressure washer handle

Ammo of choice- marbles

Operating pressure- 70-110 psi (for now)

At 70 psi I can shoot a marble through 3 aluminum pop cans both sides.

I have ordered some parts from MCmaster. They should arrive today or tomorrow. These include a 3/4 inch QEV and some supplies for my small caliber QEV musket. So expect updates within the next week.

I plan to use the 3/4 inch QEV on this gun. I will also run a copper tube to a trigger (not the washer handle) about halfway down the chamber. This will create a kind of bullpup style gun. Lastly, i plan to give her a nice coat of flat black paint.

looks good. I think your pressure waher handle is a liitle overkill but oh well. what is your piston made of?

@The Death o' Fall
Looks good, how much does the pressure washer handle throw the barrel off when shooting?

@jon_89
It's probably 3/4" pipe and fittings, though I could be wrong.

yeah i know. I just kind of had it laying around the garage.

Piston is 3/4 inch cap with tape. Neoprene bolted on the front.

The washer handle doesn't mess it up at all. It really accurate because I have someplace to hold.

Oh yeah and my name is "The Death Of All"...

I know, I was just playing mind games with people again...

uhhm okay..

Thed eat ho fall wrote:I will also run a copper tube to a trigger (not the washer handle) about halfway down the chamber. This will create a kind of bullpup style gun.

Finally, I've been promoting this idea for more compact launcher for ever! You can go one better and use syringes and piping instead of the copper tube and and make it a hydraulic system

It does look a bit overkill with the pressure washer handle but hey, if it works

jackssmirkingrevenge wrote:It does look a bit overkill with the pressure washer handle but hey, if it works

Yes, if it works...
It may or may not make a difference with pressure washer handles, but with personal experience and what I have heard over the forums about blowguns placed upside down... I might want to be careful with accidental firing when air leaks though the handle and triggers the QEV, but then again I don't know if it matters because it is a pressure washer handle...

Maybe someone should shed some light on whatever this is...

@ MR dew. I had some difficulty with the washer handle. It started leaking and I was pissed because it is brand new. I took it apart, and found some teflon tape blocking the seals (my bad ). It works great now.

when i was inside it, I noticed something interesting. The washer valve it built almost the same as a blow gun valve, but beefier and it can be used in both directions. (please don't comment on this phrase )

With the rating being 4000 psi and about 8-12 gpm, i am inclined to use these from now on. This one cost me $19.95 from northern tool (which is really nice because the ones at local stores cost $55 +). It took over a week and a half for shipping though.

Anyway, I built this gun to have a piston valve cannon under my belt before i started my next. I wanted to make a large GB coaxial. 4inch chamber and 1 1/2 inch sdr 21 barrel. GGDT predicts over 450 FPS at 80 psi.

In the mean time, i received my order from mcmaster, but i decided not to install the 3/4 inch QEV because it would be WAAY overkill.

Finally, I've been promoting this idea for more compact launcher for ever! You can go one better and use syringes and piping instead of the copper tube and and make it a hydraulic system

I really like bullpup designs. The cannon that got me started was really awsome. It was a QEV cannon, all copper and had a white handle. It won some contest on one of the European forums. I cant remember who made it, but thank you whoever you are.

EDIT---I found it, by a chance of luck. It was Hotwired's copperhead prime. God I love that gun...

As cool as hydraulics sound, its a little complicated. I'd rather make a push button valve similar to MRR's and place it into a handle.

thedeathofall wrote:Okay so this is the first gun i have posted, although not the first made. It is a coaxial piston cannon. It is the first working piston cannon i have created and I LOVE this thing.

Specs

Overall- 52 inches

Chamber- 16 inches of 1 1/4 inch pvc

Barrel- 35.5 inches of 1/2 inch sdr 21

Exhaust- 1/4 inch QEV piloted by a pressure washer handle

Ammo of choice- marbles

Operating pressure- 70-110 psi (for now)

At 70 psi I can shoot a marble through 3 aluminum pop cans both sides.

I have ordered some parts from MCmaster. They should arrive today or tomorrow. These include a 3/4 inch QEV and some supplies for my small caliber QEV musket. So expect updates within the next week.

I plan to use the 3/4 inch QEV on this gun. I will also run a copper tube to a trigger (not the washer handle) about halfway down the chamber. This will create a kind of bullpup style gun. Lastly, i plan to give her a nice coat of flat black paint.

Hello!
Please could clarify some doubts? Any modification was made in the valve? The filling of the chamber could be made the inlet of the high pressure gun? Sorry my English because I used the Google translator. Once again thank you.