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Posted: Mon May 18, 2009 5:27 pm
by Brian the brain
That would be a perfect design to fire 12 grams out of.

Put them in...pierce the back, wait....and release!!!!!!

Posted: Tue May 19, 2009 1:21 am
by littlebro05
Hmm you could probably make a magazine feed for that by using two O-rings instead of one.... where magazine is between the two o-rings and the ball in dent was infront of it... Come to think of it.. this would make a really good compact automatic pistol XD...

Posted: Tue May 19, 2009 4:51 pm
by jackssmirkingrevenge
As was pointed out, this is very much similar to my valveless prototype. One thing of interest is that the skirt of an airgun pellet is just as good a seal in a tight barrel as a rubber seal.

I've been looking at this concept more closely lately as it promises to be more simple and efficient than my pop-off auto experiments, and in a sense it is a pop-off design in its own right.

I'm currently playing with a micro calibre BBMG, not really practical along the lines of a controlled rate of fire because of the vortex mechanism and tiny chamber volume but the principle has a lot of promise in my opinion.

Posted: Tue May 19, 2009 6:24 pm
by LeMaudit
As was pointed out, this is very much similar to my valveless prototype.
You though about that first, no doubt :D

This concept is both simple to make, and as powerful as it can be. For a first airgun I think I will adopt it, and move to more complicated designs later.

Now I am hesitating between a big bore 1-shot rifle with something like a 2 inch3 - 400psi chamber to experience power, or stick to my first wish to make a pistol, and make a two or three barrel with less power (1 inch3 and short barrel) but maybe more fun!

BTW my shock pump arrived at the shop. Am I the first nuts that have no bike and no PCP airgun, but a brand new shock pump? :lol:

Posted: Tue May 19, 2009 6:46 pm
by JDP12
Hmm I like it...

This may be what I'm looking for for a pistol!

Posted: Tue May 19, 2009 7:36 pm
by LeMaudit
I just had an idea and tried to put a 3/8 steel ball inside a standard tool air quick coupling from Home depot... it seems to fit perfectly!!!!!! :shock:

With a little piece of thin rubber to improve the seal against the ball (maybe not even necessary) we may have here a perfect high power trigger for 3/8" steel balls. 8)

Please Jack, don't tell me you already experimented and documented that idea! Please, please, someone else, at least :-D

Posted: Tue May 19, 2009 7:45 pm
by JDP12
wow...

That's beautiful!

Really nice work here man. I suppose an air coupler makes perfect sense.... I'm definitely being inspired.

And I think you are the first to think of this..

Did you try shooting one out? All you'd have to do is slide back the coupler...

and it should shoot out!

Try it!

Posted: Tue May 19, 2009 7:59 pm
by mark.f
Well, see, iltbsu, there's a reason those couplings don't spew all the air out of your compressor whenever you unhook an air line. :lol:

But it would be simple to remove the check mechanism in the coupling. After that, your only obstacle would be attaching a barrel.

Posted: Tue May 19, 2009 8:00 pm
by JDP12
:P

lol duh...what was I thinking...

sorry i'm kind of out of it...focusing on my math final tomorrow.

*facepalmheaddeskcombo*

Posted: Tue May 19, 2009 8:16 pm
by Mitchza89
:shock: Don't you love it when things just "work"!

This is something I must try. Attaching a simple trigger to the coupler to pull the sleeve back could work very well.

Move over QEV guns, time for a new fad :D

Posted: Tue May 19, 2009 8:53 pm
by LeMaudit
Nah, can't shoot ! :-D

As mark.f said it needs some additional work to remove the closing mechanism. I have no idea how this can be done, I need to examine more closely the inside of the coupling or find a link that shows that.

I'll try to check if the air pressure is well sealed with a ball inside using my small workshop compressor.

Posted: Tue May 19, 2009 9:14 pm
by JDP12
I thought about this- I was thinking- if I understand the workings of it correctly- the spring inside it controls the check valve- when the coupling is inserted it pushes that back and releases air.

What if you make a projectile with a smaller rod coming out the back that would open the valve?

This would solve one of the problems I was thinking about- controlling the flow of air when reloading..otherwise it would just stream air unless you used something to control the reservoir, which is an unnecessary complication.

Also, how would you reload this? Right now I'm seeing a manual reload, Welrod type reload..

you could move the coupler back from the barrel... But then you'd have to move the reservoir as well..

Posted: Tue May 19, 2009 9:23 pm
by mark.f
Well, you can get the couplers without the check mechanism in them, or you can take it out. I forgot how to do it, so I'll see if I can find a coupler to go toy with.

Posted: Tue May 19, 2009 11:16 pm
by LeMaudit
Don't you love it when things just "work"!
Not really... now I am considering a small bore 3/8" instead of a 9/16" for big game... just because the trigger if almost done! :(
Damn laziness... Drag me off my dreams :lol:

Posted: Wed May 20, 2009 1:49 am
by jackssmirkingrevenge
LeMaudit wrote:Please Jack, don't tell me you already experimented and documented that idea! Please, please, someone else, at least :-D
The idea came to mind but I never actually made a prototype :P

This could easily be turned into a semi-auto with burst disk performance, I've been thinking about the concept and will make a few drawings/animations when I'm home.