making the blow-forward breech work

[jackssmirkingrevenge]

Am I completly wrong about the last post, is it a hammer valve because it uses momentum like a hammer

It is a hammer valve technically, and so it needs to be cocked.

I love that movie btw

[iknowmy3tables]

hehe I have an arsenal of fail pics

anyways I still haven't been able to get this to work, but with ant's sucsess this can be a fail idea

some things I'm going to try: increase stroke length to increase momentum, decrease dead space, posibly a larger hammer valve, make a tighter fit on the larger part of the bolt,
and to make it less clumsy with he back of the bolt having to pop in and out of the pipe with the hammer valve I'm going to have the bolt held in one continuous pipe with large groove were the pipe originally wasn't

[jackssmirkingrevenge]

It's a tricky, tricky act to balance, good luck. And lol at the DVD rewinder

[JDP12]

time to get in on this discussion, I have an idea about this, but I'm finishing up my drawing right now. When i get the chance later today, i will post it for your scrutinizing JSR....

muhahahahahah... lol

[jackssmirkingrevenge]

Curious to see what you'll come up with

[JDP12]

sounds good, can't wait to get it analyzed... I'll give you a hint, it could potentially involve a detachable spring that could potentially be helped out by pneumatics... lol... i still have to draw it up to see if it will work, but in my head right now at least the first part seems achievable, don't know so much about the pneumatic part...

I'll post it ASAP

[iknowmy3tables]

a pneumatic return eh, that ould be awesome if the presure seal doesn't slow it to much

[jackssmirkingrevenge]

A pneumatic return eh, that would be awesome if the presure seal doesn't slow it too much

I had made something of the sort on one of my combustion cartridge prototypes:



The idea was that I could alter the compression by changing the pressure of the reservoir, and also the delay caused by the piston drag would give the next cartridge more time to fall into place after the previous one would be ejected.

[JDP12]

k, i've scratched my current design and now have what i believe will be a very successful cross between a blowback and blowforward. I can't post the drawing yet, i need to get access to a scanner. I'm currently at school, and there are a couple scanners but i'm not at one right now, give me a bit of time and i should have it, or i'll have to wait till i get home... I'll give some hints away though.... there are no springs whatsoever.... I'll repeat that, there are NO SPRINGS WHATSOEVER. it's entirely pneumatic... take guesses if you want, but you'll just have to wait for the drawing lol. As soon as i can get to the hardware store i'll build a prototype for you all and see how it works. There will be some tuning required, but it should work dandy once that is done...

just think... no springs.... no resistance for the bolt... keep guessing lol.. I will use this design for my marble machine gun..

feel free to guess away please.

my only request is to please let me do the testing/prototyping on this valve. As far as i know, this idea has never been done before and i would like to try it out on my own first. After i get it working and everything feel free to use it, but I would just like to get the credit for creating it. Not because I'm an egostical prick, but because i want a valve design i can call my own. I'm tired of copying off of other people's, and i think this one will really work, so i want to be able to say i created my own valve, instead of, oh i used JSR's design or whoever's design.

Thanks,

ILTBTU

[Antonio]

I am curious to c the drawings:). But keep in mind that everything.. most things we come up with already existed before. I mean paintball is so much ahead of us. >Those markers must have to best valves. But yeah plz post ur ideas, bc ur teasin lol.

[JDP12]

but what fun is using existing stuff when you can build and curse at and spend sleepless nights working on your own??

Pictures coming when i get home.

[JDP12]

woooooooot!!!!!! picture!!!!!!!!!... JSR'S thing i was talking about can be found here.
http://www.spudfiles.com/forums/6mm-sem ... 10075.html

its not so much a blowforward bolt as it is a blowforward and blowback bolt combined into good old .......borwrack goodness...lol..... :)

the only problem i might see is figuring out how to get it to fire so the bolt gets pushed back before the valve triggers again.. I figured out though that i can adjust that by increasing and decreasing chamber volume and pressure.
Good old high school gas laws come into effect here! (wait, i'm still in high school...lolz..)

oh yea, the back part is BTB's marble machine gun bolt. Take a look at his thread for details about that, that's not what i'm focusing on.
sorry for the double post, just wanted people to notice this..
I'm soooo pumped up about it!! can't wait to test it!!!!

please don't start ripping on it right away about how bad I will fail. I'll just try even harder to prove you wrong... give it a chance.

<img src="http://i157.photobucket.com/albums/t79/ ... 1207187837">

[Antonio]

I saw a similar pic like this on brians posts. I dont really get why you dont need a spring for the system to recycle or not to stick''. Would be great to c it working:)

[JDP12]

k you don't need a spring, because it operates similar to an AK47- the air behind the projectile goes up that black tube and pushes the bolt back again in place. Then it fires, the projectile goes down the barrel, air goes up the black tube, pushes the bolt back, and the whole process begins again.

I should learn how to make animations... anyone know any good tutorials??

An animation for this should clear it up for a fair amount of people.

I'll get it working as soon as i can, all i have to do is make a run for the hardware store. The prototype will be small scale first, probably inside a large syringe so i can see what is happening and tune it. I'll post pictures and a video when i get it operational.

[Antonio]

So what kinda valve are you using here? A slide over valve>> or a poppet one? I dont c the benefit of this one over the blowforward poppet breech. You will always experience problems with recocking when the pressure of the airsource drops. The best I idea I have seen so far is the one of jack> a piston with a poppet at the back. The problem is that it needs lots of parts. But yeah go for it; it will prob look pretty cool. But keep in mind> a gun like an ak always has the same pressure as each round contains roughly the same amount of energy.


Btw why dont you post this under your own name and not jacks? Give urself some credit/respect:) Its also hard to find things back when these posts become so long (8 pages).