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Dam Buster(Contest Applicant)

Unread postPosted: Sat Sep 30, 2006 10:46 pm
Author: MrCrowley
Gun Name: "Dam Buster" by Mr. Crowley

Type:Pneumatic
Caliber:Golf Ball
Barrel Length:1.8m(70")
Chamber Length:1.2m(50")
Chamber Size:100mm(4")
Material:PVC
Pressure:around 100psi
Resivoir volume:?
Valve:Barrel Sealing Piston, Exhausted by spring activated 1/2" ball valve
Power Source:Air Compressor
Ammo:Golf Balls


Finaly its here my BSP golf ball gun 2months in the making.
I named it after the "Dam Buster" a bomb capable of bouncing on water over German fences that protect their Dams during ww2, a dam buster bomb had dimples on it like a GB hence the name of my gun! :D

ive got a 100mm(4") chamber 1.2m long, that goes into a 80mm(3") 90* elbow, that goes into a 80mm piston housing,the piston is filled up by a presta valve with a schrader adapter and i can exhaust the pilot with a spring activated 1/2" ball valve or a 1/4"blow gun.the trigger some of you are familiar with as i used it on a horseshoe nail shooting gun thingy.i havnt tested the gun yet as my compressor crapped out on me :evil:

now for two crappy pics from my phone as my camera dont work.
Image
Image

Unread postPosted: Sat Sep 30, 2006 10:57 pm
Author: killagorrila99
DAMB MAN! Nice gun, Did u use the tut from BCvids?

Unread postPosted: Sat Sep 30, 2006 11:11 pm
Author: MrCrowley
nah, although it helped alot in my younger days on how to build a BSP

Unread postPosted: Sun Oct 01, 2006 12:06 am
Author: Flinchy
nice job man, ha your one of the few that has a safety feature on your ball valve with that string. awesome. i bet you get some good range with GBs.

-flinchy

Unread postPosted: Sun Oct 01, 2006 12:51 am
Author: killagorrila99
Its not a safety feature, Its to make the ball valve open quicker.

Unread postPosted: Sun Oct 01, 2006 12:53 am
Author: MrCrowley
Flinchy wrote:nice job man, ha your one of the few that has a safety feature on your ball valve with that string. awesome. i bet you get some good range with GBs.

-flinchy


yeah it would look like a saftey feature as i didnt hook up the spring in that pic just the trigger setup thing to stop it turning when the spring is on

Unread postPosted: Sun Oct 01, 2006 2:49 am
Author: Brian the brain
nice, reminds me of Chappy...

Unread postPosted: Sun Oct 01, 2006 4:08 am
Author: CpTn_lAw
what kinda PVC is that?

Unread postPosted: Sun Oct 01, 2006 4:23 am
Author: MrCrowley
normal, its all PN18(260psi) aprt from the barrel is PN12(170)
i painted it olive drab

Unread postPosted: Sun Oct 01, 2006 5:05 am
Author: experament_u2
nice gun i like the idear behind it

Unread postPosted: Sun Oct 01, 2006 5:13 am
Author: killagorrila99
Brian the brain wrote:nice, reminds me of Chappy...



THats what I was thinking, Is this or chappy more powerfull?

Unread postPosted: Sun Oct 01, 2006 11:41 am
Author: noname
So this is why you haven't posted a cannon in ages. Looks great, too bad I don't have a compressor or I would have some seriously huge monsters.

Unread postPosted: Sun Oct 01, 2006 12:27 pm
Author: Velocity
Nice piston valve! And good paintjob as well: it is very uniform (or so it appears).

I have always wanted to use screws on a piston valve. This isn't for any reason in particular; i just thought it looked cool. But hey, I guess I should be thankful that I can just use common PVC fittings.

I've noticed a large increase in the number of people who are able to build piston cannons, and I am very glad to see it. A year ago or so, at least on spudtech IIRC, most of the cannons submitted by members were sprinkler valve or ball valve ones. I guess I shouldn't be pissed off at the sprinkler valve cannons, but I have never had a sprinkler valve cannons perform well.

Anyways...

Do you put dishsoap on that ball valve? I just did for the first time yesterday (just wanted to see what a difference it made), and man, was it huge! It was truly effortless. I find it helps the most if you shut the valve, and pour a bit on the ball part, then open and close it a few times. Problem is, the dishsoap will harden up a bit over time, and make it a bit harder to open and close (still easier than without any dishsoap at all)

Geez, 3 tangents in a one post?

Ok... i'll stop now... awesome cannon you got there

Unread postPosted: Sun Oct 01, 2006 2:37 pm
Author: MrCrowley
rmich732 wrote:Nice piston valve! And good paintjob as well: it is very uniform (or so it appears).

I have always wanted to use screws on a piston valve. This isn't for any reason in particular; i just thought it looked cool. But hey, I guess I should be thankful that I can just use common PVC fittings.


Yeah i did it for two reasons:
1:screws look way cool on pistons
2:if the piston craps out i can fix it......not that its gonna crap out :roll:

killagorrila99 wrote:
Brian the brain wrote:nice, reminds me of Chappy...



THats what I was thinking, Is this or chappy more powerfull?


well his has a 53mm bore barrel so thats too big for GBs and GBs are the best distance/power ammo
his is smaller dia chamber and slightly smaller piston but hey his brother made it and its still a nice cannon.

Unread postPosted: Sun Oct 01, 2006 4:51 pm
Author: MrCrowley
i forgot to add but if some of you are wondering the disk thingy around the piston end cap is neoprene rubber stuff to stop the piston leaking as the screws may not get an air tight seal as i had to sand down the end cap.