How far does it go!

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I just wanted to see if anyone can suggest anything for more power. I have 4 2” valves coming into a 16 foot long exhaust pipe for a barrel. All are quick exhaust modified valves. A 2” ball valve is then opened to fire. A 1 pound project I made of spackle and a 4 inch Christmas globe had a hang time of 16 second at a 61° angle, 120 psi. Can someone help me with the math for velocity or flight travel? Thanks

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Holy moly, looks like you're trying to blow up the moon friend, lol
Let me dust off my old that math part of my brain, I can't factor for wind resistance but I got 89.64m/s or 294.1fps as your estimated velocity work math attached
That's only based on the flight time and the initial angle and assuming a vacuum And a 9.8m/s^2 acceleration of gravity. To calculate based on the cannons specs like using the GGDT program I'd need the dimensions of your air chamber and maybe a better picture of the chamber and valves
Let me dust off my old that math part of my brain, I can't factor for wind resistance but I got 89.64m/s or 294.1fps as your estimated velocity work math attached
That's only based on the flight time and the initial angle and assuming a vacuum And a 9.8m/s^2 acceleration of gravity. To calculate based on the cannons specs like using the GGDT program I'd need the dimensions of your air chamber and maybe a better picture of the chamber and valves

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My mistake I forgot your initial question of how far does it go,
Expanding the math a little bit ideally it flew 695meters or 2281feet
It's probably short of that distance a good bit because that doesn't factor drag resistance, is anyone here familiar with drag coefficients?
Expanding the math a little bit ideally it flew 695meters or 2281feet
It's probably short of that distance a good bit because that doesn't factor drag resistance, is anyone here familiar with drag coefficients?
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