Works just like the Nazi V3 cannon, but uses compressed gas (currently nitrogen for safety) instead of pyrotechnic propellants.

Longshot Space: Business is Booming

https://www.youtube.com/watch?v=dvSHpGAtJ9k

https://www.longshotspace.com/technology

Multi-injection guns like Longshot?s current prototype spread the acceleration of the projectile out over time, but have a similar top speed to a traditional cannon. The speed is limited by the top speed of the gas, which is determined by the gas composition and temperature.

For room temperature nitrogen, this is a maximum of just over Mach 4 - about one sixth the speed needed for space launch.

By moving the system to the desert, Longshot can use hydrogen as the accelerant gas. By extending the length of the barrel to 500+ meters and adding more boosters, Longshot will be able to accelerate payloads of up to 100 KG to Mach 5+ at acceleration loads that your cell phone can survive, and at prices significantly lower than current rocket-based accelerator systems.

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I saw this beautiful girl on the bus, but she looked sad. I asked her what was wrong. She said, "Well, my analyst said I'm a nymphomaniac, but I only like Jewish cowboys... by the way, my name is Dianne." I said, "Hello, Dianne. My name is Bucky Goldstein." - Steven Wright

I think potato cannons should be allowed in paintball wars as "artillery".
Potential injuries ? Yepper.

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When in doubt, WHACK the GAS and DITCH the brake !!!

Yes, there is such a thing as NORMAL, if you have to ask what is "NORMAL" , you probably aren't !
Failure may not be an OPTION, but it is ALWAYS a POSSIBILITY.
ALL systems are GO for MAYHEM, AGITATION, CHAOS, TURMOIL, FIASCOS, AGGRAVATION, INSTIGATION, NUISANCE-ACTION, and HAVOC !