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 61 users online :: 5 registered, 0 hidden and 56 guests


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

Registered users: Bing [Bot], Google [Bot], Google Adsense [Bot], MSNbot Media, Yahoo [Bot] based on users active over the past 5 minutes

The Team
Administrators
Global Moderators
global_moderators.png CS

Anyone use a 2" valve before??

Post questions and info about pneumatic (compressed gas) powered cannons here. This includes discussion about valves, pipe types, compressors, alternate gas setups, and anything else relevant.
Sponsored 
  • Author
    Message

Anyone use a 2" valve before??

Unread postAuthor: Atattack » Tue Sep 13, 2011 3:44 pm

I am looking at a 2" valve and am worried about the recoil. Would like to hear from someone who has personally fired or has known someone who has a gun with a 2" valve with a CV of atleast 80+. It is a Goyen 2" dust collector valve. Link to valve is below.

http://www.piiny.com/goyen/pdfs/CA_RCA_50T.pdf

The muzzle energy is @ 276 ft/lbs if that helps with 150 psi

Thanks for the help.
  • 0


Atattack
Staff Sergeant
Staff Sergeant
 
Posts: 123
Joined: Fri Aug 19, 2011 8:33 am
Reputation: 0

Unread postAuthor: jazzman56 » Tue Sep 13, 2011 4:41 pm

Where can i buy that????



:D
  • 0


jazzman56
Specialist
Specialist
 
Posts: 53
Joined: Wed May 11, 2011 4:52 am
Reputation: 0

Unread postAuthor: Atattack » Tue Sep 13, 2011 4:43 pm

  • 0


Atattack
Staff Sergeant
Staff Sergeant
 
Posts: 123
Joined: Fri Aug 19, 2011 8:33 am
Reputation: 0

Unread postAuthor: Gun Freak » Tue Sep 13, 2011 4:43 pm

I'm not sure of the cv of a 2" qdv but I know they have serious recoil especially with heavy projectiles.
  • 0

OG Anti-Hybrid
One man's trash is a true Spudder's treasure!
Golf Ball Cannon "Superna"M16 BBMGPengunHammer Valve Airsoft SniperHigh Pressure .22 Coax
Holy Shat!
User avatar
Gun Freak
Lieutenant General
Lieutenant General
 
Posts: 4969
Joined: Mon Jan 25, 2010 4:38 pm
Location: Florida
Country: United States (us)
Reputation: 11

Unread postAuthor: Atattack » Tue Sep 13, 2011 4:47 pm

Reason I am asking is it would be almost half the cost to use a 1.5" valve. Talked to an engineer at Goyen and he said I should stay away from 2" due to recoil and stay with a 1.5". Guy was very intelligent but was not a spudder so figured I would ask on here.

I am wanting to make a really nice gun so it is worth it to spend extra $ to get a nicer valve but if I can only use 2" at 100 psi and I would be able to fire 1.5" at 150 psi then I will be better off with smaller valve.

Both valves can be used at 150 psi just worried about recoil.
  • 0


Atattack
Staff Sergeant
Staff Sergeant
 
Posts: 123
Joined: Fri Aug 19, 2011 8:33 am
Reputation: 0

Unread postAuthor: jackssmirkingrevenge » Tue Sep 13, 2011 6:16 pm

Atattack wrote:Both valves can be used at 150 psi just worried about recoil.


[youtube]http://www.youtube.com/watch?v=u0KPS-PjcWo[/youtube]

A muzzle brake and recoil absorbtion system would make interesting design features.

Ronnie Barrett didn't see the 50 BMG round and think "This round is fuçking awesome, I will take out some powder to make it comfortable to shoot in a rifle."

Ronnie Barrett saw the 50 BMG round and thought "This round is fuçking awesome, even though I know nothing about firearms or engineering I will make a rifle that can fire it comfortably"

Image

;)

Footnote: J.D. Jones did take out some powder and made an awesome silent sniper round, but that's beside the point.
  • 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: Technician1002 » Tue Sep 13, 2011 6:49 pm

My 2 inch port QDV videos are in this youtube channel. Check the uploads. The worst recoil is when oversize barrels are used. A three inch barrel with Gatoraid is the highest recoil item shot. My shots are all 100 PSI or less.

http://www.youtube.com/user/Technician1002

With lower pressure and lighter projectiles, the recoil is quite manageable. The tshirt shot below is about 35 PSI.

Trust me on this one, You do not want to shoulder fire a Gaitoraid in a 3 inch barrel at 100 PSI on a 2 inch high CV valve. This one left a bruise.
[youtube]http://www.youtube.com/watch?v=9Klxqav_6NM[/youtube]
[youtube]http://www.youtube.com/watch?v=XsSTxCP8rvY[/youtube]
  • 0

Last edited by Technician1002 on Tue Sep 13, 2011 7:21 pm, edited 7 times in total.
User avatar
Technician1002
Chief of Staff
Chief of Staff
 
Posts: 5190
Joined: Sat Apr 04, 2009 11:10 am
Reputation: 14

Sponsored

Sponsor
 


Unread postAuthor: Atattack » Tue Sep 13, 2011 6:50 pm

HMmmmm, you bring up some good points as usual JSR, :D . I am using a 3" aluminum schedule 40 for the pipe that is 48" long. When making a muzzle brake do I just drill holes in last 6" of pipe?

Any ever make a recoil absorption system? I was planning on having a curved piece of metal come down chamber to rest against shoulder. The gun is going to be a shoulder based launcher, so hopefully that will make it easier to incorporate a absorption system.
  • 0


Atattack
Staff Sergeant
Staff Sergeant
 
Posts: 123
Joined: Fri Aug 19, 2011 8:33 am
Reputation: 0

Unread postAuthor: Atattack » Tue Sep 13, 2011 6:54 pm

I plan on using a 3" barrel to launch water balloons so will be heavy and oversized, so that is why I will either need to go to 1.5" or compensate for recoil, JSR has me wanting to compensate now, that sounded bad, :).
  • 0


Atattack
Staff Sergeant
Staff Sergeant
 
Posts: 123
Joined: Fri Aug 19, 2011 8:33 am
Reputation: 0

Unread postAuthor: Technician1002 » Tue Sep 13, 2011 6:58 pm

Start with low pressure. I have launched raw eggs without breaking them.
  • 0

User avatar
Technician1002
Chief of Staff
Chief of Staff
 
Posts: 5190
Joined: Sat Apr 04, 2009 11:10 am
Reputation: 14

Unread postAuthor: jackssmirkingrevenge » Tue Sep 13, 2011 7:07 pm

  • 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: Atattack » Tue Sep 13, 2011 7:28 pm

After reading muzzle brake thread I think I am leaning towards a suppressor because will have numerous people around when using this and am a little concerned about people saying muzzle brakes can be very loud. Anyone know how suppressor compare to muzzle brakes as far as recoil efficiency?

That recoil system looked pretty complicated to make. I am trying to figure out how I can do it with the butt coming down from the chamber rather than traditional way of having it built into back of stock.
  • 0


Atattack
Staff Sergeant
Staff Sergeant
 
Posts: 123
Joined: Fri Aug 19, 2011 8:33 am
Reputation: 0

Unread postAuthor: Fnord » Tue Sep 13, 2011 7:38 pm

I don't think ~300 foot-pounds M.E. is much to worry about.
If, for example, your projectile weighs 1/3 of your gun weight, you'll be absorbing somewhere around 100 ft-lbs of recoil. That's a lot, but I'm sure your proj/gun weigh ratio will be nowhere near this high.

Consider that 400+ foot-pounds of recoil energy is entirely survivable, but dangerous and often comical for those around you.

After a quick calculation I believe I've personally taken somewhere between 100-150 ft-lbs with an unpadded wooden stock. It was quite unpleasant, but still managable (this was with an old combustion gun shooting a barrel full of water).

Edit; If you're using a large chamber at high pressure you'll want to take into account them recoil from the gas itself. Add its recoil energy to your total. Air weighs ~1.2 grams/liter and will be traveling around 300 m/s (1100 fps) worst-case scenario.
  • 0

Last edited by Fnord on Tue Sep 13, 2011 7:46 pm, edited 1 time in total.
User avatar
Fnord
Major General
Major General
 
Posts: 2244
Joined: Tue Feb 13, 2007 9:20 pm
Location: Pripyat
Reputation: 7

Unread postAuthor: Atattack » Tue Sep 13, 2011 7:42 pm

I could be doing the GGDT calculation incorrectly then, not positive about that M.E. #. I am using 150 psi, projectile will weight 6 oz. Valve is 2" with 88 C.V. Barrel is 3"x48" and Chamber is 3" x 48". Open time is 70ms. I figured with a projectile that heavy is would kick pretty bad.
  • 0


Atattack
Staff Sergeant
Staff Sergeant
 
Posts: 123
Joined: Fri Aug 19, 2011 8:33 am
Reputation: 0

Unread postAuthor: Fnord » Tue Sep 13, 2011 7:50 pm

Your opening time is way to slow. Play with this number and you'll see you could be getting ME's of over a thousand ft-lbs, which sounds reasonable.

Still with a 6 oz projectile I wouldn't worry about it too much. That video JSR posted had way more recoil than this will. It all depend on how much your gun weighs.
  • 0

User avatar
Fnord
Major General
Major General
 
Posts: 2244
Joined: Tue Feb 13, 2007 9:20 pm
Location: Pripyat
Reputation: 7

Next

Return to Pneumatic Cannon Discussion

Who is online

Registered users: Bing [Bot], Google [Bot], Google Adsense [Bot], MSNbot Media, Yahoo [Bot]

Reputation System ©'