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Posted: Fri Jul 27, 2007 1:31 pm
by frankrede
A wider barrel would not help you get higher velocities, but you would get more power, as long as the barrel didn't exceed your valves size(bottleneck)
Posted: Fri Jul 27, 2007 1:32 pm
by CannonBall
@spudblaster15 srry i dont understand your english.. im dutch and my english is not so good.
you mean i will see a huge performance increase?
I think the damage aint enough and i built this fucker for supersonic so i want to have this thing At sonic speeds.
Posted: Fri Jul 27, 2007 2:32 pm
by SpudBlaster15
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Posted: Fri Jul 27, 2007 3:02 pm
by frankrede
Higher velocity does not mean more power, a bowling ball going 50 fps will do more damage than a marble at a thousand fps/
simple as that/
Your cannon is only a cannon and you can only expect so much out of it.
Posted: Fri Jul 27, 2007 3:15 pm
by paaiyan
frankrede wrote:Higher velocity does not mean more power, a bowling ball going 50 fps will do more damage than a marble at a thousand fps/
simple as that/
Your cannon is only a cannon and you can only expect so much out of it.
This is true, but for this particular application, an increase in velocity will mean an increase in energy, as he will most likely be using the same projectiles.
On a side note, I really need to build a hybrid and take it to the lake.
Posted: Fri Jul 27, 2007 6:17 pm
by CannonBall
@spudblaster you say about 40% +- well how did you get this awnsers..
Did u do math?
I made a miss calculation... my C:B is 0.94/1 I measured inside diameter this time
So a 3 meter barrel would give me a C:B of 0.62/1
4 meter would give me 0.47/1
but i dont want it to be longer then 3 meters that would really suck , a 4 meter barrel that makes a 90 degree angle from its own weight lol
But wow shit 40% that is over mach1 for sure..
well i want to shoot threw a concrete wall 8) just kidding.. but i want the same muzzle energy/speed that a small fire arm would have.
ive made a video today shooting from 5 meters distance.. the bang from the cannon and projectile impact are very close to each other..
first cannon then projectile impact .. i guess no supersonic yet
Spud15 could you calculate what a 1 meter extension would do for my speed ? or is there a way to predict gun performance?
Posted: Fri Jul 27, 2007 7:09 pm
by SpudBlaster15
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Posted: Sat Jul 28, 2007 3:31 pm
by boilingleadbath
Woah, you guys where able to calculate this using EVBEC?
I didn't think you would be able, as a typo (woops) in one of the error blockers prevented me from modeling the scenario.
(For some dumbass reason, I was calculating the C:B ratio at that step by multiplying the diameter by the length of the respective parts - D*L / D2*L2)
Yeah, I didn't notice that until yesterday.
It won't impair accuracy, but it won't allow you to model some scenarios you should be able to.
Posted: Sun Jul 29, 2007 6:20 am
by CannonBall
well ive did some calculations.. with my 2 meter barrel i wont get past 860 fps but with a 3 meter barrel and 7x mix look... C:B 0.94/1
5x = 1.288 = 1.3 + 4 bar 926.5 fps
6x = 1.545 = 1.55 +5bar 951 fps
7x = 1.80 = 1.80 + 6bar 968.5 fps
This would be a C:B of 0.62 / 1
well if would enlarge my barrel with 1 meter its alot more power
With a C:B of 0.35/1 it will shoot far more then mach 1 like mach 1.3 ..
Posted: Sun Jul 29, 2007 6:23 am
by jackssmirkingrevenge
frankrede wrote:Higher velocity does not mean more power, a bowling ball going 50 fps will do more damage than a marble at a thousand fps/
simple as that/
Your cannon is only a cannon and you can only expect so much out of it.
On the other hand, if we think of power in terms of kinetic energy (for this is the mechanism by which non-explosive projectiles do their damage), we know that keeping the same velocity but doubling the weight gives double the power. On the other hand, doubling the velocity for the same weight gives 4 times the power, hence velocity is a good thing to have

Posted: Sun Jul 29, 2007 10:37 am
by CannonBall
did a new calculation here it is

1149 joules at 6 times mix 20 grams projectile
speedpicture is calculated @ 5x mix 10grams projectile
i dont know what i did wrong last time but i have a 300 fps increment
Posted: Tue Sep 04, 2007 4:18 pm
by CannonBall
I finnaly got a better barrel.. and a 2" Cam lock
My 2" Cam lock gives nice flow! to a 28mm barrel
My C:B is 0.32: 1 chamber = 476 ML barrel 3 meter 28 mm
I shoot my hybrid a 6x or 7x fuel = Propane
Would this give me super sonic speeds
Projectile weighs 10 grams.
Thanks !