How much velocity do you need to comfortably reach 300 meters range with a cannon?

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An0nim
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Fri May 12, 2023 5:23 am

I want to build a pneumatic cannon and I have some cool ideas but I don't have much experience with them.

I want to know how much pressure/air volume you need to achieve a 300 meters range comfortably (so no shooting at a 30-45 degree angle).

I would also appreciate some tips on making the cannon accurate and on achieving consistent velocities.

My goal is hitting 1x1 meter target at 100 meters with the first shot since it seems a reasonable range yet it's not so easy to achieve as to be boring.

Thanks in advance!
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mrfoo
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Sat May 13, 2023 12:56 pm

At an average walking speed, it'll probably take you between 3 and five minutes, longer if it's uphill. The limiting factor is going to be how heavy the cannon is, but you can probably mitigate that by fitting it with wheels, at that point it's all down to terrain.

Sensible answer, it depends, amongst other things, on what objects you're trying to propel. A marble is different to a golf ball is different to a chunk of potato is different to a melon or a bowling ball.
jimmy101
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Mon May 15, 2023 11:44 pm

300 meters is a long way.

Remember that a pneumatic is probably going to be operating at less than 150 PSI, which is the max pressure of a typical shop compressor. Compare that to a typical 0.22 rifle that has an effective range of about 150 yards. That low power rifle operates at twenty thousand PSI. So you are going to be pressure limited.

As to hitting anything at 100 yards, that will be difficult without a rifled barrel or a aerodynamically stable round (bulletss are not aerodynamically stable).
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jackssmirkingrevenge
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Sat Jun 10, 2023 8:25 am

jimmy101 wrote:
Mon May 15, 2023 11:44 pm
300 meters is a long way.
There are people driving projectiles by with air that are hitting targets at that range and beyond:



As you've pointed out however, what they are using are closer to firearms in terms of projectiles and manufacturing than your average spud gun.

The higher the velocity, then the flatter the trajectory and the more likely it is one will hit the target, but the most important factor for accuracy is consistency. Consistent velocity, consistent projectile shape and weight and a consistent interaction with the barrel.
hectmarr wrote:You have to make many weapons, because this field is long and short life
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Wed Mar 06, 2024 11:58 am

nice work I will use that to take notes and make improvements to my spudgun
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