Finally, 4SPC completed (4" Sweet Piston Cannon)

[SpudUke5]

I know i havent been posting frequently, but i have been just lurking, finding the right moment for me to post a comment. But im still here

Well i finally got my 4 inch piston cannon completed. It was a big project, but i managed to get it done. All my parts are pressure rated, but i have my concern about the pipe because i saw some lines on the pipe and i dont know if those are possibly stress lines, so i will take a picture as soon as i get the camera from my mom.

Enough rambling and on to the Specs:
Pilot: 3/4 inch QEV from mcmaster piloted by a 3/4 inch ball valve
Piston: 3 inch endcap
Sealing face: 1/8 inch thick neoprene from Mcmaster
Barrel: 3" 10'
Chamber: 4" 8'

My fittings are mostly from Sprinkler.com except the 4x3 bushing, which i screwed up the first time, so i bought it from Mcmaster.

She gives nice recoil at 30 with no barrel.

I have used my cannon a little and it was good, but i still have some problems to fix and some things to finish.
I need:
a barrel support
a breech loading
something to support my sealing face
paint it
name it

I have used my gun to 60 psi, and its pretty powerful, but i havent been using ammo that completely fits 3", but that wont be a problem as soon as i make some pykrete.

Since my piston is an endcap, and the face is rounded, i need to make it straight, so that my piston wont leak. So i at first had a 4 inch OD grinding wheel, which didnt last long because when it would slam against the barrel to seal, it would start to break, until one side was just completely broken. So that was removed and i tried it without. Worked fine, until 30 psi, where the sealing face passed the ID if the barrel and it would release the air.

So my question is, which washer would be good enough for a something to support my sealing face, where in the presence of force would not bend nor deform?

Would this be good? 91117A260 on mcmaster

Pictures are not possible now due to the lack of a camera at the moment, but will be here soon.

EDIT:

the cannon


Pilot setup with a 1/4 cross from mcmaster


3" 10' barrel


Front of piston


Side of piston


Back of piston


Comparison from small piston tee gun to my big one


Broken grinding wheel that was my sealing face support

So what do you think? I have a question but i forgot it, if i remember ill edit.

[jrrdw]

Name it "Finally". For the sealing face, use a metal washer that is allmost the inside diameter of your barrel. That will keep the rubber from sucking into the barrel.

[STHORNE]

sounds like an awesome gun. hope you find a camera soon... I wana see some pics of this beast you speak of lol.

name suggestion = the "Breath-Taker"

[Blitz]

Heh heh, this will be more powerful than CF -- nice job! Can't wait to see it.

[Eddbot]

or "Finality"
message too short

[SpudUke5]

That not a bad idea eddbot, i like breath taker as well, or breath giver, because of how much air this thing outputs

Thx jrrdw, ill just look for one on mcmaster and them ill confirm it with you if you think its good.

[STHORNE]

for the name, you could even do something bad ass like...

"Grave-Digger" or "Death Whistle"

but its all up to you....

[SpudUke5]

You got some nice ideas for names.
Im not that creative so i will rely on you guys.

I will take those into consideration though.

Would this be good? 98264A200 on mcmaster

[elitesniper]

The ''Why Cannon''?

[STHORNE]

Why the "why" lol.

[XxtriviumxX]

The "4" Piston Cannon"

Cant wait for some pics.

[SpudUke5]

Well i need something more creative, lol but thx or suggesting.

My mom should be home soon from the auction so i will be taking the camera and loading pictures.

[bigbob12345]

how bout something simple like the 4in sweet piston gun or 4inSPG

[STHORNE]

that sounds pretty cool for something along military lines.

or even simpler, "4SPG"

[bigbob12345]

4SPG
I like it
Lets see if LikimysCrotchus5 likes it too