Pneumatic air cannon without proyectile

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Technician1002
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Wed Sep 09, 2009 7:08 pm

I did some more testing today. I dug out the larger cannon and did some tests at only 50 PSI.

The first test was done with the 4 inch barrel because the 4:1 expansion worked well on the little cannon. At 50 PSI the results were terrible. I knocked over only 3 bottles and no cans. For this to work high pressure is required to get the expansion to the larger barrel.

The second test was done with the short tennis ball barrel. Results were not bad for 50 PSI.

I then moved up to the long 2 inch barrel and managed to clear a path to 23 feet.

Knocking over stuff at a distance with the muzzle blast of an air cannon isn't easy.
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The 2 inch long spud barrel did the best with a high speed blast that tossed the near bottles, blasted over the near can and then rolled out to 25 feet dropping over bottles as it went.
The 2 inch long spud barrel did the best with a high speed blast that tossed the near bottles, blasted over the near can and then rolled out to 25 feet dropping over bottles as it went.
This tennis ball barrel did much better with an obvious slow moving blast that slowly tumbled bottles as it rolled down the line.  It barely knocked over the can at 15 feet.
This tennis ball barrel did much better with an obvious slow moving blast that slowly tumbled bottles as it rolled down the line. It barely knocked over the can at 15 feet.
I knocked down just 3 bottles.  A breeze came up and kept knocking the rest down, so I have just a photo of the launcher prior to the shot.
I knocked down just 3 bottles. A breeze came up and kept knocking the rest down, so I have just a photo of the launcher prior to the shot.
THUNDERLORD
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Wed Sep 09, 2009 9:19 pm

jarm0591 wrote:
JSR wrote:Does it have to be air that transfers the energy? Can you use the air to power a piston that physically smacks into the can, without shooting off itself?
I can use a piston, but I have to smack the can with the air....
Yeah!yeah!,
A 20+ foot telescoping captive bolt,
with some type of fan at the front! :P 8)
I Wonder how temperature of the air fired will effect performance?
edit:seems like colder would work better(?)
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tomthebomb137
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Sun Sep 13, 2009 4:22 pm

I may text my pulse valve cannon for this as that is actually what a pulse valve is designed to do, knock things with blasts of air (they are used in dust collectors).

Also what are the actual rules for the testing envoirnment, i.e. does it need to be outside or can it be in a confined area?
i love finding loopholes :D
"Once the pin is pulled, Mr. grenade is no longer our friend"

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