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advanced golf ball combustion (now with a video)

Posted: Sun May 04, 2008 9:39 pm
by jook13
So I have spent a long time making this one.

She is a metered onboard propane cannon that shoots golf balls. The C:B ratio is right around 3-1 so its louder than others, but I love the big bang. I was planning on a 12 foot barrel but it was way to hard to move around that way.

I tried my best to hide any wires for the fan and ignition. I think I did pretty well with that. Everything that could ever need to be replaces or worked on is accessible via unscrewing (which cost me a LOT more than if I didn't worry about it)

This gun took me about 2 months to build. Mostly because work has been slow and 4" sch 40 pvc fittings are ridiculously priced. All together it has cost in the 300 dollar range to build.

The specs:

chamber: 40 inches of 4" pvc
barrel: 94" of sdr 26 pvc sleeved inside of shc 80 pvc
ignition: gutted stun gun
Other: chamber fan with switch, 2" ball valve vent, onboard propane meter, comfortable handle position

The gun weighs about 60 pounds, but the handles make it easy to hold since its nicely balanced.

Anyways I only did one real shot with a golfball and the result was impressive as you can see in the pics below, such a clean hole in the door.

anyways, here she is, I am pretty proud of it. I put a lot of work unto her.

VIDEO LINK!:
http://smg.photobucket.com/albums/v13/j ... I_2765.flv

Posted: Sun May 04, 2008 9:40 pm
by elitesniper
Just beautiful! but something about overunders turn me off, I like the look of inlines, nonetheless nice :D

Posted: Sun May 04, 2008 9:44 pm
by jook13
haha... not a fan of the over unders? if this was an inline it would have been over 12 feet long. I like how the over under design compacts it.

Posted: Sun May 04, 2008 9:48 pm
by sjog
Compacts it and supports the barrel.
Good job!!

Posted: Sun May 04, 2008 9:51 pm
by daxspudder
very nice build, handles could be more ergonomic though, any pics of the innerds? maybe rearrange the propane mount to make it more appealing to the eye, i like the way (i assume) you can access all your internal components through the handles. ever thought of wasting a watermelon with a golf ball? id love to see those pictures. i give it an 7 of 10.

Posted: Sun May 04, 2008 9:58 pm
by jook13
You know, I was kinda dissapointed at how much taller the handles were than I thought they would be. They ended up being like that because of how big the fittings were that allow me to unscrew and get to the innards.

I mounted the propane like it is so that it is upright as I fill it and also so I could just screw it into the barrel support instead of hose-clamp or tape it to the chamber. Its all a bunch of give and take options. I am happy with the choices I made though.

As for the shooting a watermelon comment, next weekened I am going out shooting with a few friends. I will put a golf ball through a watermelon, a cpu monitor, a scanner, a printer, a fax machine, a can of soup, some ply wood, some glass jars, and I will get video and photos of it all.

Posted: Sun May 04, 2008 9:59 pm
by BigGrib
Overall nice work. Like elitesniper, I've never been a big fan of over/under for combustions, but you have done an outstanding job putting this together. I was wondering how your barrel supports are connected to the chamber and if they are open to the chamber. I'm supposing not due to the fact that your barrel is going right through them but it is a question to ask anyway. The only other thing that kind of bugs me is your placement of the fan switch underneath the barrel on the support column. I would have wired it in to the second handle so you don't have to let go of whichever handle to turn it on and off. Otherwise good job, and I'd love to see some more damage pictures.

Posted: Sun May 04, 2008 10:05 pm
by jook13
the barrel supports are connected by epoxy. they are insanely snug and strong (they hold my 180 pounds of body weight). I like the chamber fan switch placement. while shooting I leave the switch on. when I am done I turn it off. I have to reach further to open the vent valve anyways. I guess it would have been neat to have it on the other handle, but I didnt think of it. thanks for the compliments man. And I cant wait to get more damage done.

Posted: Sun May 04, 2008 10:08 pm
by taytayswims
beautiful gun mate!!!!!! i like the colors too

Posted: Sun May 04, 2008 10:22 pm
by biggsauce
Nice cannon there mac

Where is your fan located?

Posted: Sun May 04, 2008 11:11 pm
by jook13
thanks buddy. the fan is located as close to the ball valve vent as it can get. it blows air into the chamber and vents it out the barrel. thanks for the kind words, it means a lot after seeing your clean gun you just posted.

Posted: Sun May 04, 2008 11:15 pm
by biggsauce
No problem, but just a suggestion:

Try either moving the fan towards where your propane enters the chamber, or adding a fan or two. You fan now is fine for venting, but it doesn't seem to felp mix your fuel/air very well. And evenly mixed fuel/air combination should increase your performance.

EDIT: and secure your meter. it would be a shame for it to break out of your chamber or weaken where the meter enters your chamber and possibly blow out. Still great cannon though

Posted: Sun May 04, 2008 11:55 pm
by starman
Yeah, put me in the group that prefers inline combustion guns.

My first impression was to look at it a little sideways trying to figure it out. The "handle stacks" are overkill for sure, mostly adding just extra weight. The handles do look comfortable though. It also seems you could have done something different with the propane holder...it's sort of just stuck there with an oddly long hose dripping down to your meter pipe. The meter also looks not very well mounted on the hose end.

Otherwise it does have a decent look to it while you're holding it there and extra points for taking the time to give it the two tone paint job. The big chamber and a good size barrel will equal pretty decent performance almost by default. It looks like that golfball barely even saw that door in its way..:) I also like the 2" vent valve...helps round out the overall large look of the thing.

Posted: Mon May 05, 2008 12:04 am
by jook13
thanks for the comments guys. I will most definitely support the meter on the hose end.

One thing I really like about the propane tank holder placement is that it acts like a kick-stand. it keeps the gun upright as I fuel, vent, or load the ammo.


It also seems you could have done something different with the propane holder...it's sort of just stuck there with an oddly long hose dripping down to your meter pipe. The meter also looks not very well mounted on the hose end.
I have read that it is wise to keep the propane canister upright or at least have some of the hose or meter pointing upwards so that there is no liquid getting into the gun. if this is false, I could place the propane somewhere more appealing, but for now, if this is true, I choose function over fashion.

Posted: Mon May 05, 2008 12:56 am
by daxspudder
okay, just a suggestion, but i think your propane would fit nicely in the forward handle mount, mounted horizontally, connecting end forward, that way when you charge your metering section point the gun up and you dont have to worry about liquid in the chamber, very nice though.