How to build an auto system

[SNDM]

NOTE: THIS IS NOT MY DESIGN, I DID NOT COME UP WITH IT. I WILL NOT BE TAKING CREDIT FOR IT. WHOEVER MADE IT CAN COME FORWARD AND CLAIM THE DESIGN IF THEY WISH.
II THIS DESIGN HAS BEEN POSTED REGULARLY FOR AROUND 6 YEARS, I AM VERY SORRY, BUT IT IS A NICE PICTURE I MADE.
But you can love me for making this guide.

---THE DESIGN---

I have built a gun out of this design, I will try and get pictures ASAP.
Anyway, the design is at the bottom, cos I dunno how to move it.

It is pretty self explanatory, but I will give a run-through:

1.) Air is supplied into back of bolt.
2.) Bolt is pushed forward into open space, pushing forward ammo and sealing off magazine.
3.) Air floods round into holes in bolt, driving ammo out into the world.
4.) Spring pushes bolt back, as pressure has been lost.
5.) Rinse, Lather and Repeat.

Building this isnt too hard, in fact, its easy if you have a spare afternoon kicking around.

Im not going to tell you how to build this, as it is easy, and personally, I think everyone deserves a challenge and the chance to think for themselves.

Through Babelfish: I cant be bothered. Go figure.

Enjoy.

Does anyone know the name of this design or theory of operation?

[Tom]

Does anyone know the name of this design or theory of operation?

This is the famous Blow forward unit as Jack called it. If you aren't telling us how to build it why did you posted it in the how to section .
G's from the Dutch,Tom

[THUNDERLORD]

This is the famous Blow forward unit as Jack called it. If you aren't telling us how to build it why did you posted it in the how to section

Good question Tom. BTW what is "G from the Dutch"? Just wondering.

This bolt design to pnuematics is like the browning link to handguns IMO.
It's actually more than that but it's a way to time everything and there are other uses for it like in hybrid design.

There are other concepts I am tinkering with like useing it as a piston itself like a spring air design.(different than this diagram version though)

I have still another design for it but it's a secret until I can perfect it.

I call it a blow forward bolt also JSR mentioned that it was long ago patented but his version is my personal favorite design.
Besides I don't think you can patent an idea or principal but only a particular working design. 8)

BTW sorry but If I can build one good enough I might use it to take over the world instead of posting it here also. 8)

[SNDM]

Whoopsies, shall I move this?

[Brian the brain]

G from the Dutch most likely means Greatings from the Dutch.

Tom is, like me, Dutch


We are growing in numbers...
about to take over this site completely..

mu...muhah...muhahahaha.....

Anyway..Thanks for the effort to inform us, although your attempt was futile.You had no way of knowing..
Sharing ideas is what it's all about...

[psycix]

Hi there my fellow dutchmans, nice wheather in holland this week isnt it?

This mechanism is called a Blow Forward Bolt, quite applicapable.

[jimmy101]

The design is used on RC warships. Sometimes called a BB selector gun. Below is a similar design constructed in a 1/4" compression T.

[kablooie]

Yeah, the design is pretty basic, I have made the BB selector model, and it is a lot of fun, but has really bad flow. All it took for me was to get a tee and then drilll out one of the ports, add a spring and the compression tube that came with it and I have semi auto (albiet low power). Got to go, good luck!

[Antonio]

let me raise the dutchness on this post:) Too bad we lost against russia yesterday...

@SNDM, you are talking about an auto system> this is only a small part of it. Why not ellaborate on it and show us how you plan to trigger this system"".

[jackssmirkingrevenge]

hmmm, I had missed this. Unfortunately with a constant supply of air the device is hard to build as an auto. It will either hang open, or cycle so fast that it's impossible to use as an auto mechanism.

You can see my attempts at making it function here.



If you find a way to pulse the air going to it, then it will make a good semi/full auto launcher.

[jimmy101]

If you find a way to pulse the air going to it, then it will make a good semi/full auto launcher.

In RC warships they use a CO2 source and a hammer valve operated by an RC solenoid to get semi auto. (Full auto isn't permitted in RC warship battles.)

Is the problem with full auto the back pressure caused by the ammo in the barrel? The back pressure is added to the spring force causing the breech to retract before the current shell has left the barrel?

[Hailfire753]

JSR, when it cycled too fast to feed, was it gravity-fed or spring?

[jackssmirkingrevenge]

I doubt it, I couldn't get it function whether there was ammunition in the breech or not.

[Antonio]

@jsr, you prob could. I think if we think of some antichop system it might work bc then the system keeps cycling eventhough a ball is only halfway in the breech. Dont ask me what it should look like(the antichop system like on a tippmann) but we could do some more brainstormin:)

[Antonio]

sorry for double post
Something like this (automag), check when it misfires. I know its not like our system...but yeah: