Login    Register
User Information
Username:
Password:
We are a free and open
community, all are welcome.
Click here to Register
Sponsored
Who is online

In total there are 49 users online :: 5 registered, 0 hidden and 44 guests


Most users ever online was 155 on Mon Aug 15, 2016 1:40 am

Registered users: Bing [Bot], Google [Bot], Google Adsense [Bot], Majestic-12 [Bot], Yahoo [Bot] based on users active over the past 5 minutes

The Team
Administrators
Global Moderators
global_moderators.png CS

Sonic boom>?

Post questions and info about hybrid (compressed gas with fuel) powered cannons here. This includes discussion about fuels, ratios, ignition systems, build types, safety, and anything else relevant.
Sponsored 
  • Author
    Message

Unread postAuthor: frankrede » Fri Jul 27, 2007 1:31 pm

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)
  • 0

Current project: Afghanistan deployment
User avatar
frankrede
Lieutenant General
Lieutenant General
 
Posts: 3220
Joined: Thu Jul 20, 2006 9:47 pm
Reputation: 0

Unread postAuthor: CannonBall » Fri Jul 27, 2007 1:32 pm

@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.
  • 0

User avatar
CannonBall
Staff Sergeant
Staff Sergeant
 
Posts: 102
Joined: Tue Mar 20, 2007 5:16 pm
Reputation: 0

Unread postAuthor: SpudBlaster15 » Fri Jul 27, 2007 2:32 pm

If you extend the barrel, you will not likely see a huge increase in performance.

If you extend the barrel A LOT, you will see a larger gain. Given your current C:B ratio, doubling the barrel length will give you a ~40% increase in muzzle energy.

What do you want to destroy that you cannot already?
  • 0

People should not be afraid of their governments. Governments should be afraid of their people.
User avatar
SpudBlaster15
Major General
Major General
 
Posts: 2385
Joined: Wed Oct 18, 2006 11:12 pm
Location: Canada
Country: Poland (pl)
Reputation: 3

Unread postAuthor: frankrede » Fri Jul 27, 2007 3:02 pm

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.
  • 0

Current project: Afghanistan deployment
User avatar
frankrede
Lieutenant General
Lieutenant General
 
Posts: 3220
Joined: Thu Jul 20, 2006 9:47 pm
Reputation: 0

Unread postAuthor: paaiyan » Fri Jul 27, 2007 3:15 pm

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.
  • 0

"Who ever said the pen was mightier than the sword, obviously, never encountered automatic weapons."
-General Douglass MacArthur

Read my dog's blog - Life of Kilo
User avatar
paaiyan
Major General
Major General
 
Posts: 2140
Joined: Wed Dec 27, 2006 10:03 pm
Location: Central Oklahoma
Country: United States (us)
Reputation: 1

Unread postAuthor: CannonBall » Fri Jul 27, 2007 6:17 pm

@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 crap 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?
  • 0

User avatar
CannonBall
Staff Sergeant
Staff Sergeant
 
Posts: 102
Joined: Tue Mar 20, 2007 5:16 pm
Reputation: 0

Unread postAuthor: SpudBlaster15 » Fri Jul 27, 2007 7:09 pm

  • 0

People should not be afraid of their governments. Governments should be afraid of their people.
User avatar
SpudBlaster15
Major General
Major General
 
Posts: 2385
Joined: Wed Oct 18, 2006 11:12 pm
Location: Canada
Country: Poland (pl)
Reputation: 3

Sponsored

Sponsor
 


Unread postAuthor: boilingleadbath » Sat Jul 28, 2007 3:31 pm

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.
  • 0

User avatar
boilingleadbath
Moderator
Moderator
 
Posts: 1642
Joined: Sat Mar 12, 2005 10:35 pm
Location: Pennsylvania, USA
Reputation: 0

Unread postAuthor: CannonBall » Sun Jul 29, 2007 6:20 am

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 ..
  • 0

User avatar
CannonBall
Staff Sergeant
Staff Sergeant
 
Posts: 102
Joined: Tue Mar 20, 2007 5:16 pm
Reputation: 0

Unread postAuthor: jackssmirkingrevenge » Sun Jul 29, 2007 6:23 am

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 :)
  • 0

User avatar
jackssmirkingrevenge
Donating Member
Donating Member
 
Posts: 24225
Joined: Thu Mar 15, 2007 11:28 pm
Country: Holy See (Vatican City State) (va)
Reputation: 66

Unread postAuthor: CannonBall » Sun Jul 29, 2007 10:37 am

did a new calculation here it is

Image


Image
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
  • 0

User avatar
CannonBall
Staff Sergeant
Staff Sergeant
 
Posts: 102
Joined: Tue Mar 20, 2007 5:16 pm
Reputation: 0

Unread postAuthor: CannonBall » Tue Sep 04, 2007 4:18 pm

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 !
  • 0

Modifying my hybrid.
Status
Cameraflash/carcoil ignition
2" Cam lock (idiot flow!)
3 meter barrel 25 mm

Damage..
Shot threw a house door!!
pierced 8 centimeters in a tree
User avatar
CannonBall
Staff Sergeant
Staff Sergeant
 
Posts: 102
Joined: Tue Mar 20, 2007 5:16 pm
Reputation: 0

Previous

Return to Hybrid Cannon Discussion

Who is online

Registered users: Bing [Bot], Google [Bot], Google Adsense [Bot], Majestic-12 [Bot], Yahoo [Bot]

Reputation System ©'