MrCrowley wrote:Water is going to drain out of a 2" hole much faster than a 3/4" hole, so yeah it does matter unless you have 10' or so long barrels.

Well that was easy to understand... yeah that does make sense.

It's a shame about the o-ring problem, I found on the V.A.L it was much easier to just use threaded adapters sometimes it's just hard to find the right ones. Other than that, and the very small porting, it looks pretty good. :)

edit: Your piston must be pretty damn heavy, are you even using a ...

Sorry, by "plug" this is what I meant...

http://www.bestbuypoolsupply.com/media/redbushing.jpg

Terminology... :roll:

Put the o-ring groove on the "front/pressure side" and the bolts where you have them.

Good strength, removable...and it seals. :)

I see what you mean but finding a plug to ...

You should consider buying an El'cheapo red dot scope

http://www.canadiantire.ca/AST/browse/5/SportsRec/1/Hunting/RifleSpottingScopes/PRD~0755532P/Tasco%252BRed%252BDot%252BScope%25252C%252B1%252Bx%252B30.jsp

It adds great to a spudgun as you can really see around the target and the potato flight ...

How have you made the o-ring groove?

I made the o-ring groove by using the edge of a drill bit the same diameter as the o-ring. If you do this, it helps to start it with a hacksaw first so the bit has a groove to start in. Just keep at it until your oring just barely sticks out.

HOWEVER, Gippeto ...

OK, OK...After reviewing it again, I see where you are going with this.

I can insert 6 new bolts in front of the oring (toward the barrel).

OR

I can glue a 2" coupling over the leader, fit another 2" extension and redo the o-ring either in the endcap or at the very end of the new leader... :? but ...

I would stop using that immediately! :shock:

With the o-ring groove being that deep, there isn't much material left to handle the force of the piston hitting the endcap let alone handle the loads induced by pressure.

It could...and likely will...fly off...with some "oomph" behind it.

What's ...

Thats a very nice build :thumbright:

But two things :

1- the barrel seal is pretty small for the barrel size, it looks ready to break with the weight of the barrel ...

2- the sealing problem might be on the barrel seal, try to sand it to a very fine grit if you still can ( i've seen a little ...

I Created this cannon based off of MrCrowley's SGA Golf Ball Gun but made some of my own tweaks, mods, and style behind it. So PROPS to MrCrowley for the baseline design idea.

Chamber: 2" sch 40 PVC - 36" in length not including the bends

Barrels:
1) 2" spud barrel 22"
2) 3/4" barrel 30" with ...

Dang it! I really tried to check everything after reading a lot of posts here, it says PVC 324 but after just checking it again it does say dwv in small letters. What does that limit me to?
After looking again it looks like one of you bushings isnt glued all the way in either, I wouldnt use the ...

Dang it! I really tried to check everything after reading a lot of posts here, it says PVC 324 but after just checking it again it does say dwv in small letters. What does that limit me to?

After many many do overs I finally came up with a working model. It's a pretty basic cannon but performs exceptionally well. I realized that I was trying to get too complex too early with pistons and leaks and all that so I decided to tone it back and get a working model. This is just a basic 3/4 ...

Awesome, I'll try a couple different ideas here. Thanks! Great Forum!!

Interesting and makes sense. I have a 1/8" gap of free space around the BB in the barrel. Internally it only allows enough space for the BB to leave the vortex block but I can see that the air will also be coming out around the BB rather than just simply pushing it inside the barrel. I'll look for ...

OK, I could not wrap my mind around it for a minute. How was I able to make a medicine bottle and a bic pen case shoot faster than an 80 PSI air gun. It must be pressure. I glued a bic pen to the barrel output and as a leader into the larger aluminum barrel and I have better results. It definitely ...