Search found 258 matches

by Marffy
Sat Dec 01, 2012 7:12 pm
Forum: Pneumatic Cannons
Topic: Simple coaxial shotgun
Replies: 16
Views: 6644

heres a little update:

barrel in the chamber:
Image

the piston:
Image

it started to leak today so i opened it up to see what was wrong
by Marffy
Sat Dec 01, 2012 1:08 am
Forum: Pneumatic Cannons
Topic: Simple coaxial shotgun
Replies: 16
Views: 6644

jackssmirkingrevenge wrote:Do you mean a cork cork or a rubber "cork"?
wine cork, so.. rubber cork.
by Marffy
Thu Nov 29, 2012 8:35 pm
Forum: Pneumatic Cannons
Topic: Simple coaxial shotgun
Replies: 16
Views: 6644

jrrdw wrote:
jackssmirkingrevenge wrote:Looking good, hope your piston can take the strain of higher pressures.
I was also wondering about that. Cork piston could be a first here...
I used to shoot corks out of 3/4" barrels so thats where i got the idea. Its working great so far. It doesn't need a bumper and won't crack in half
by Marffy
Wed Nov 28, 2012 11:56 pm
Forum: Pneumatic Cannons
Topic: Simple coaxial shotgun
Replies: 16
Views: 6644

Nice simple gun you've got there, great work with the stock. Did you roughen up the inside of that hose barb and your barrel? If so it looks like you're ready for some high pressure fun :D no, i just left it as i got it. i didn't think of doing so untill after i glued it. one side is filled with ho...
by Marffy
Wed Nov 28, 2012 11:43 pm
Forum: Pneumatic Cannons
Topic: Simple coaxial shotgun
Replies: 16
Views: 6644

Simple coaxial shotgun

So i finally finished my muzzle loading piston air gun. I've only taken it to 150psi but its got some good power, can't wait to bump up the pressure. Specs: Chamber: 2' .75" galvanized steel Barrel: 36" .5" OD steel tube ~.44 cal pilot: 1/4" modified blowgun fill valve: schrader the piston is a wine...
by Marffy
Sun Nov 25, 2012 4:17 pm
Forum: Pneumatic Cannons
Topic: Piston shotgun build help
Replies: 14
Views: 3972

It's just a support, look for something that fits the OD of the barrel, and the ID of the chamber. A cotton reel is one idea, but there's heaps you can use. I just jam some Al tubing in the gap and epoxy it. alright, i tryed using wood hot glued to the barrel, but when when i threaded the barrel in...
by Marffy
Sat Nov 24, 2012 7:57 pm
Forum: Pneumatic Cannons
Topic: Piston shotgun build help
Replies: 14
Views: 3972

Ran into a problem today. Where the barrel meets the piston, The barrel wobbles around there. I think i need some kind of a brace to keep it from wobbling but it needs to let the air flow thru at the same time. What have you guys used to stop this?
by Marffy
Thu Nov 22, 2012 12:32 pm
Forum: Pneumatic Cannons
Topic: Piston shotgun build help
Replies: 14
Views: 3972

looks like a pain, and i might get the barrel crooked. i'll just hope to find a longer tube at a different hardware store i'm going too, If that fails i'll have to do that /\

i could possibly sleeve the two barrels together too
by Marffy
Wed Nov 21, 2012 11:40 pm
Forum: Pneumatic Cannons
Topic: Piston shotgun build help
Replies: 14
Views: 3972

One important thing to note is that a thin walled barrel used at high pressure will over time dig into your piston like a cookie cutter. My other piston cannon has that problem. every other shot it either cuts the seals or the piston cracks in half. The tape is a good idea however i might use an ep...
by Marffy
Tue Nov 20, 2012 6:20 pm
Forum: Pneumatic Cannons
Topic: Piston shotgun build help
Replies: 14
Views: 3972

jackssmirkingrevenge wrote: If you're using a shock pump, 2 feet of 3/4" pipe will take forever to get up to 300 psi. Don't forget that HPA pneumatics do well even with small volumes
I was thinking a normal compressor for testing, and co2 cartridges/ regulated hpa tank for power.

Still have no idea where to get a barrel
by Marffy
Mon Nov 19, 2012 6:54 pm
Forum: Pneumatic Cannons
Topic: Piston shotgun build help
Replies: 14
Views: 3972

MrCrowley wrote:Yes, it's safe. .
alright cool, i was just worried it the trigger would blow up in my hand.

Now, does anyone know where i can get some pipe of a certain small caliber that will hold up to the pressure?
by Marffy
Mon Nov 19, 2012 5:56 pm
Forum: Pneumatic Cannons
Topic: Piston shotgun build help
Replies: 14
Views: 3972

I'm looking for it to act like and look like a shotgun, but a muzzle loader. Basically its going to be around 2 feet of 3/4 pipe on a wood stock. thinking about it .22 might be a little small, but i want something that can fit a slug type projectile (a pellet) and to shoot shot (#9 shot maybe) But i...
by Marffy
Mon Nov 19, 2012 12:05 am
Forum: Pneumatic Cannons
Topic: Piston shotgun build help
Replies: 14
Views: 3972

Piston shotgun build help

Its been a while and i'm thinking of making a new gun. I wanted to make a shotgun type co-axial? piston gun. With a 3/4" steel tube and a schrader valve as a pilot valve, i'm wondering if the schrader valve will work as a good pilot? or can i use something bigger that will hold around 300psi that is...
by Marffy
Tue Apr 24, 2012 7:12 pm
Forum: Pneumatic Cannons
Topic: Mauler valve for sale
Replies: 7
Views: 1910

Mail it to me :) or just put a chamber and barrel on it...
by Marffy
Sat Apr 21, 2012 6:05 pm
Forum: Pneumatic Cannons
Topic: Epoxy vs oily barrel
Replies: 5
Views: 1373

Yeah. Just remotely fill it to at least 100 (150 or 200 to test its limits) and see if it shoots out