Rob Allen Posted November 19, 2008 Share Posted November 19, 2008 This may be extremely obvious or even previously mentioned in another thread and I've missed it, but has anyone tried firing a shell via spud cannon? When I shoot a blank I can get plenty of 'ignition' flame for the fuse. I'll just have to try it I guess, I can launch shells pretty damn high in the traditional BP lift arrangement but when firing projectiles from the cannon with little more than deoderant, they seem to go further.. Link to comment Share on other sites More sharing options...
Miech Posted November 19, 2008 Share Posted November 19, 2008 Although it is likely it works, I seriously would recommend against shooting shells from your shoulder. At least assure the cannon is made of fiber glass or another suitable material, the PVC these cannons usually are made of is plainly dangerous. Link to comment Share on other sites More sharing options...
Rob Allen Posted November 19, 2008 Author Share Posted November 19, 2008 Although it is likely it works, I seriously would recommend against shooting shells from your shoulder. At least assure the cannon is made of fiber glass or another suitable material, the PVC these cannons usually are made of is plainly dangerous. I wouldn't dream of firing from my shoulder, a live shell... I was thinking of securing it to a post in the ground and firing electrically from a safe distance. My cannons are pressure pipe PVC I've fired many projectiles over 4 years and never encountered any problems, I will give it a go but am keen to know if anyone else as already and what the results were like? Link to comment Share on other sites More sharing options...
tentacles Posted November 19, 2008 Share Posted November 19, 2008 (edited) It might work, I'm not convinced that the air-fuel burning of a spud gun will be hot enough to light the fuse, unless carefully primed. Maybe I'm wrong. Miech's concerns regarding the PVC are *very* valid. PVC (unless otherwise marked!) is NOT a high-impact plastic, and will fracture under the kind of duty you're putting it to. I HAVE seen high-impact PVC, it's usually used for buried water pipe and is clearly marked "high impact". It would work better, but still not nearly as well as HDPE. FrankRizzo has a section of PVC that he had x-rayed before retiring it from spud gun service and the x-ray results were frightening. How many times do you have to encounter problems before you regret it? This is a similar argument to many k3wls - like that kid that blew himself to pink mist in his parents' living room with 400g of AP. Edited November 19, 2008 by tentacles Link to comment Share on other sites More sharing options...
Rob Allen Posted November 19, 2008 Author Share Posted November 19, 2008 It might work, I'm not convinced that the air-fuel burning of a spud gun will be hot enough to light the fuse, unless carefully primed. Maybe I'm wrong. Miech's concerns regarding the PVC are *very* valid. PVC (unless otherwise marked!) is NOT a high-impact plastic, and will fracture under the kind of duty you're putting it to. I HAVE seen high-impact PVC, it's usually used for buried water pipe and is clearly marked "high impact". It would work better, but still not nearly as well as HDPE. FrankRizzo has a section of PVC that he had x-rayed before retiring it from spud gun service and the x-ray results were frightening. How many times do you have to encounter problems before you regret it? This is a similar argument to many k3wls - like that kid that blew himself to pink mist in his parents' living room with 400g of AP. I'm pretty sure the Air fuel mix burnt is hot enough, only one way to find out though, I'm pretty sure the PVC I'm using is the 'buried pipe type', from memory it can withstand constant pressure at 160-180 psi.. from memory..? Anyway it blowing up doesn't bother me as I won't be anywhere near it when I set it off. Link to comment Share on other sites More sharing options...
tentacles Posted November 19, 2008 Share Posted November 19, 2008 Not all buried pipe is high impact - if it isnt' marked, then it's not. As always, use at your own risk, etc. Try smashing a piece of your pvc with a hammer, just give it a few hard whacks and see how it handles it. Hit it near the end, and I bet you'll chip off chunks. Link to comment Share on other sites More sharing options...
FrankRizzo Posted November 19, 2008 Share Posted November 19, 2008 The pipe we had x-rayed was serving duty as the pressure vessel for a pneumatic gun (75-120PSI), so it was exposed to many expansion/contraction cycles. Normal combustion guns rarely see pressures greater than 15-22PSI with propane propellants. With proper priming, I can't imagine that it couldn't work. We used to attach pieces of 000 steel wool to potatoes, and it had no trouble getting lit by the combustion gases. Link to comment Share on other sites More sharing options...
Rob Allen Posted November 19, 2008 Author Share Posted November 19, 2008 Not all buried pipe is high impact - if it isnt' marked, then it's not. As always, use at your own risk, etc. Try smashing a piece of your pvc with a hammer, just give it a few hard whacks and see how it handles it. Hit it near the end, and I bet you'll chip off chunks. It is marked as pressure pipe and has pressure rating on it and is quite thick but I don't recall weather or not it's is marked as hpde. I'm not a plumber, so I can't quote these things off my top of my head but I'll check it out when at home. Either way won't be close enough to it to be worried about it, once I've done it I'll post results. I was hoping someone already had... Link to comment Share on other sites More sharing options...
Mumbles Posted November 19, 2008 Share Posted November 19, 2008 I'd be far more comfortable with a pneumatic type of launcher. It's much more easily controlled with electronic ignition and ensuring that the shell exits the cannon. I've had several times that the combustion chamber of my potato cannon just became so oxygen poor the potatoe would just plop out or not go off at all. I'd hate to think what would happen should it happen with a lit shell. Link to comment Share on other sites More sharing options...
Rob Allen Posted November 19, 2008 Author Share Posted November 19, 2008 The pipe we had x-rayed was serving duty as the pressure vessel for a pneumatic gun (75-120PSI), so it was exposed to many expansion/contraction cycles. Normal combustion guns rarely see pressures greater than 15-22PSI with propane propellants. With proper priming, I can't imagine that it couldn't work. We used to attach pieces of 000 steel wool to potatoes, and it had no trouble getting lit by the combustion gases. Thats pretty cool, would have looked like a tracer whizzing through the sky, could have been fun to freak out your neighbours.. ha ha Link to comment Share on other sites More sharing options...
FrankRizzo Posted November 19, 2008 Share Posted November 19, 2008 Yeah, it was a "breaking glass" comet type of effect. As the wad of steel wool would burn, pieces of burning material would drop off as it flew through the air. It was a very cool effect. Link to comment Share on other sites More sharing options...
tentacles Posted November 19, 2008 Share Posted November 19, 2008 Frank: We've gotta try that on a shell some time, lol. "What kind of comet was that?" "Steel wool" "Huh?" Link to comment Share on other sites More sharing options...
Richtee Posted November 20, 2008 Share Posted November 20, 2008 (edited) Frank: We've gotta try that on a shell some time, lol. "What kind of comet was that?" "Steel wool" "Huh?" Have one now...:{) Made a "ring" of the wool after rolling it out to about .375" diameter, and dipped it in NC. Bound to the bottom of an experimental BP cannister salute. Should be interesting! I'll try for a decent vid of it... Oh, makes for a pretty cool packing for a mine as well! Edited November 20, 2008 by Richtee Link to comment Share on other sites More sharing options...
LGM Posted November 21, 2008 Share Posted November 21, 2008 With a propane meter and a chamber fan you can get near identical shots every time. IIRC metered propane hits 80-100 psi when fired. Link to comment Share on other sites More sharing options...
JS92 Posted November 22, 2008 Share Posted November 22, 2008 like that kid that blew himself to pink mist in his parents' living room with 400g of AP.Whats AP? Link to comment Share on other sites More sharing options...
tentacles Posted November 22, 2008 Share Posted November 22, 2008 JP: An abbreviation for a notoriously sensitive yet easy to make primary high explosive. That's all I'm going to say on the subject.. Link to comment Share on other sites More sharing options...
Richtee Posted November 22, 2008 Share Posted November 22, 2008 (edited) Have one now...:{) Made a "ring" of the wool after rolling it out to about .375" diameter, and dipped it in NC. Bound to the bottom of an experimental BP cannister salute. Should be interesting! I'll try for a decent vid of it... Well...so much for the decent vid. You can get a glimpse of a rather nice shower of sparks out of the "gate", but it either burned out half way up, or the lift charge blew the 'ell out of it...not sure. Also, I wanted to do this with some ambient light, due to my cams limitations number one and number two, I wanted to see the BP smoke puff from the salute :{) Exp. BP salute with steel wool rising effect On Edit: I guess I'm a bit of a dumbass...this SHOULD be in the aerial shell section... mods, if desired, would you would be so kind? Edited November 22, 2008 by Richtee Link to comment Share on other sites More sharing options...
Richtee Posted November 22, 2008 Share Posted November 22, 2008 What grade of steel wool did you use, the same 000 that FrankRizzo specified? Nice BP salute, BTW. Hmm I guess I dont know...just had a ball of it in my shop area. From experience, I'd have to say it 00 tho. Triple would be alot more "flammable" I would think. But like I said..I'm not sure it wasn't just blown to smithereens by the lift... and thanks for the back pat :{) Link to comment Share on other sites More sharing options...
FrankRizzo Posted November 23, 2008 Share Posted November 23, 2008 Very neat, Richtee! I think you're right though, the lift seemed to decimate the steel wool ~ 12' above the muzzle. It would definitely still be a cool effect if it was a bit darker outside. The spud gun tended to have a bit more of gentle push, though if the air resistance was high enough, it would tear right off the potato. I used a paperclip spiraled into a corkscrew shape to anchor it. If you used something like a straightened piece of wire pasted into the shell, similar to pasting rope on bigger shells, I imagine you could get it to hold on 'till apogee. The air resistance might also make a cool alternative to rope for keeping pattern shells in the correct orientation too. Link to comment Share on other sites More sharing options...
Recommended Posts