A 10-32 QEV for a 40mm projectile?

Show us your pneumatic spud gun! Discuss pneumatic (compressed gas) powered potato guns and related accessories. Valve types, actuation, pipe, materials, fittings, compressors, safety, gas choices, and more.
dtitr
Private
Private
Posts: 4
Joined: Sat Feb 16, 2019 12:11 pm

Sat Feb 16, 2019 1:43 pm

Ok so, I'm new to this. I'm making a project that shoots a 40mm projectile out of a 9" barrel. I'm thinking of using this 10-32 QEV: https://palmerspursuit.com/products/qev ... 2132702855
I'm using a 16g co2 reg'ed down to ~300psi into a 3" 1/4 nipple. I'm wondering if this would provide enough airflow and pressure to shoot a 40mm projectile at a decent speed? Any tips or input?
User avatar
farcticox1
Sergeant
Sergeant
Posts: 1077
Joined: Sun Mar 31, 2013 12:37 pm
Has thanked: 68 times
Been thanked: 93 times

Sun Feb 17, 2019 9:18 am

10/32 is like 5mm, no where near enough flow :shock: your'e gonna need a BIG QEV,
A 1/2" at least https://www.ebay.ca/itm/QE-04-Pneumatic ... 0010.m2109
Or 3/4" https://www.ebay.ca/itm/QE-04-3-4-Pneum ... :rk:3:pf:0

Probably wont need 300psi at that diameter, my Nerf Rival will go 200ft at 150psi, that's 20mm projectiles with little mass to it, it uses a 3/8" solenoid valve, probably the same flow as a 1/4" QEV.
MKIII fin.jpg
This looks like a 3/4"
[youtube][/youtube]
dtitr
Private
Private
Posts: 4
Joined: Sat Feb 16, 2019 12:11 pm

Sun Feb 17, 2019 1:08 pm

farcticox1 wrote:10/32 is like 5mm, no where near enough flow :shock: your'e gonna need a BIG QEV,
A 1/2" at least https://www.ebay.ca/itm/QE-04-Pneumatic ... 0010.m2109
Or 3/4" https://www.ebay.ca/itm/QE-04-3-4-Pneum ... :rk:3:pf:0

Probably wont need 300psi at that diameter, my Nerf Rival will go 200ft at 150psi, that's 20mm projectiles with little mass to it, it uses a 3/8" solenoid valve, probably the same flow as a 1/4" QEV.
MKIII fin.jpg
This looks like a 3/4"
[youtube][/youtube]
This guy seems to have done a similar thing with some 10-32 pieces and this valve:
https://www.evike.com/products/72398/
https://www.instructables.com/id/Airsof ... ncher-Mod/
I own the taginn shell and can tell you it doesnt hold much air volume, and holds about 300psi
I'm trying to make my own though so I'm not gonna use the taginn, but I'm curious why that works with small threadings and a homemade one wouldnt, thanks.
User avatar
jackssmirkingrevenge
Five Star General
Five Star General
Posts: 26179
Joined: Thu Mar 15, 2007 11:28 pm
Has thanked: 543 times
Been thanked: 321 times

Donating Members

Sun Feb 17, 2019 8:22 pm

farcticox1 wrote:10/32 is like 5mm, no where near enough flow
Yes, this sort of QEV is more of a control valve for paintball markers, not really useful as a main valve.
a 40mm projectile at a decent speed? Any tips or input?
What's the projectile (weight, shape) and what speed would you consider decent?
hectmarr wrote:You have to make many weapons, because this field is long and short life
User avatar
farcticox1
Sergeant
Sergeant
Posts: 1077
Joined: Sun Mar 31, 2013 12:37 pm
Has thanked: 68 times
Been thanked: 93 times

Mon Feb 18, 2019 4:57 am

Airsoft ?
Grenade_4balls_lg.jpg
Grenade_4balls_lg.jpg (11.89 KiB) Viewed 4615 times
dtitr
Private
Private
Posts: 4
Joined: Sat Feb 16, 2019 12:11 pm

Wed Feb 20, 2019 9:16 pm

jackssmirkingrevenge wrote:
farcticox1 wrote:10/32 is like 5mm, no where near enough flow
Yes, this sort of QEV is more of a control valve for paintball markers, not really useful as a main valve.
a 40mm projectile at a decent speed? Any tips or input?
What's the projectile (weight, shape) and what speed would you consider decent?
Im planning on shooting something like these: http://airsoftpyrotechnics.com/airsoft- ... G4InuhKiUk
I've already picked out my valve though, I went with this one:
I also picked up a slide valve and most of my fittings are 1/4 npt. For the per-shot-tank (idk what its called) im using a 1/2 npt 3" nipple. I'm hoping that'll be enough... will it?
dtitr
Private
Private
Posts: 4
Joined: Sat Feb 16, 2019 12:11 pm

Wed Feb 20, 2019 9:18 pm

a 40mm projectile at a decent speed? Any tips or input?
What's the projectile (weight, shape) and what speed would you consider decent?
For speeds I was hoping about 150 fps over 50m.
Last edited by jrrdw on Thu Feb 21, 2019 6:23 am, edited 1 time in total.
Reason: Fixed quote tag.
User avatar
jackssmirkingrevenge
Five Star General
Five Star General
Posts: 26179
Joined: Thu Mar 15, 2007 11:28 pm
Has thanked: 543 times
Been thanked: 321 times

Donating Members

Thu Feb 21, 2019 8:48 am

I guess you're trying to make a cheaper version of this expensive toy.

Projectile weight should be about 20 grams, here is a rough simulation in GGDT:

Image

Using the parameters given 600 psi gives you about 110 feet per second. I cut down the barrel to 5 inches because due to the limited chamber volume, anything longer would actually decelerate the projectile.

By using a 1/2" valve we can drop the pressure to 500 psi and get the performance you would like:

Image



I highly suggest using GGDT to model your launcher before purchasing parts and planning dimensions.
hectmarr wrote:You have to make many weapons, because this field is long and short life
User avatar
farcticox1
Sergeant
Sergeant
Posts: 1077
Joined: Sun Mar 31, 2013 12:37 pm
Has thanked: 68 times
Been thanked: 93 times

Thu Feb 21, 2019 5:17 pm

That guy did do a good job with his though, damn it, I want to build one now.
download.jpg
download.jpg (2.98 KiB) Viewed 4353 times
hectmarr
Sergeant
Sergeant
Argentina
Posts: 1053
Joined: Sat May 07, 2016 3:49 pm
Location: Argentina
Has thanked: 262 times
Been thanked: 261 times
Contact:

Thu Feb 21, 2019 8:38 pm

farcticox1 wrote:That guy did do a good job with his though, damn it, I want to build one now.
download.jpg
We are two who want to do one of these! :bounce:
User avatar
jackssmirkingrevenge
Five Star General
Five Star General
Posts: 26179
Joined: Thu Mar 15, 2007 11:28 pm
Has thanked: 543 times
Been thanked: 321 times

Donating Members

Thu Feb 21, 2019 10:36 pm

hectmarr wrote:We are two who want to do one of these! :bounce:
Three!

It's been done in airsoft:

[youtube][/youtube]

Now imagine that with some "proper" pneumatic cartridges at a couple of thousands of psi...
hectmarr wrote:You have to make many weapons, because this field is long and short life
hectmarr
Sergeant
Sergeant
Argentina
Posts: 1053
Joined: Sat May 07, 2016 3:49 pm
Location: Argentina
Has thanked: 262 times
Been thanked: 261 times
Contact:

Thu Feb 21, 2019 11:14 pm

As the ammunition is large, you could put the compressed air on themselves. Beautiful weapon to hit annoying sellers :bom: jajajaja !!
User avatar
jackssmirkingrevenge
Five Star General
Five Star General
Posts: 26179
Joined: Thu Mar 15, 2007 11:28 pm
Has thanked: 543 times
Been thanked: 321 times

Donating Members

Fri Feb 22, 2019 3:31 pm

hectmarr wrote:As the ammunition is large, you could put the compressed air on themselves.
This is how the launcher in video works, it uses airsoft 40mm grenades that use the same ball-lock system that I have been experimenting with:

Image
hectmarr wrote:You have to make many weapons, because this field is long and short life
hectmarr
Sergeant
Sergeant
Argentina
Posts: 1053
Joined: Sat May 07, 2016 3:49 pm
Location: Argentina
Has thanked: 262 times
Been thanked: 261 times
Contact:

Fri Feb 22, 2019 4:41 pm

Its operation is very clear. It's quite simple, in general.
Post Reply