Auto-BB v 5.0 or is it 6.0?

[SPG]

Thinking about the "blow up" breach (not certain about the name, it occured to me, is THIS the solution for fully-auto?

The point of it would be, that the gas port stays closed till after the BB port has also closed, which should mean no hanging half open making a gentle farting noise.

OK, so people will mention issues of jamming with the pressure on the sliding portion of the valve, but McMaster is full of valves which work just the same way and don't have those issues.

Now, the question is, can Jack make it out of epoxy?

[Sticky_Tape]

well is the olny question even a question sure JSR can make it out of epoxy! that is a great idea I didn't like the hybrid design this is pretty cool.

[pizlo]

Some many great theorys out there... will this be the one to achieve full auto??! tune in next week to this topic.

[jackssmirkingrevenge]

Try as I might, I still see it hanging

[VH_man]

It makes sense. I might do this...... MABEY...... lol.

[SPG]

Jack, where do you think it's going to hang? I'm fairly certain because only one port can ever be open at any one time it shouldn't, but maybe you've seen something I haven't?

[judgment_arms]

I’m with jack; it’ll just equalize and come to a stop, or fluctuate with the valve opening just enough to let air in and then back out.



The idea of having a pop-off valve powered cannon is just not going to work because every pop-off valve I’ve seen is designed to keep the pressure as high as possible but below a certain PSI, often fluctuating between open and closed to do so. (i.e. farting…)

With out some uber PSI it’s just not going to work.

[POLAND_SPUD]

soo many posts and there is not even one working prototype

I think that semis are easier to build... it would be better to start with them... then building fully automatic guns would become easier....

here is my idea for a semi gun... it will work I only have to find time to build it (maybe this summer... coz my college sucks)...
anyway it is very similar to something that was proposed by some guy long long time ago

(I know this post is not relevant to the discussion - but I feel that there are to many JSR influenced schematics on spudfiles... so have a look )

[SPG]

I can't see where it'll stop, as you can see from the revised animation there's no sngle point when both ports can be open at once for it to hang. I guess the only way to know will be to make it, Jack, can your epoxy pistons seal in this kind of situation, for the sliding bolt?

A couple of revisions, firstly I flipped it upside-down, that's really only because any trigger should be underneath and that'll be what controls gas flow so it's logical to have the gas port closer. The second major part is the change of spring from a coil spring to a leaf spring which you can see flexing under the chamber. Why? A couple of reasons, spring steel is easier to buy for a start and also it's easier to change the spring rate with a simple sliding collar moving along the outside of the chamber.

In the animation you can see this operating in two positions, the first gives a soft spring, the scond a firmer spring.

[judgment_arms]

Look, I’ll explain again:
As the pressure in the chamber rises, the bolt slides down closing off the fill. Once the valve starts to open it’ll dump out a bit of air and move back, as it moves back it will either:
(a. open the fill valve just enough to let air back in and then it will slide back and open the main valve again, and it will repeat and continue to due so until the air supply is cut off.
(b. stop just short of open for either the fill or main valve.

[Brian the brain]

Won't work.
As mentioned, I too have experienced the fart problem. ( go see a doctor dude!)
I have given up on these designs.
THey tend to find a point of balancing between open and closed and not do much.THe closest I came with the snapvalve.It opened like hell, but it kept on hissing unless I released the trigger.
Also friction will play a much MUCH bigger role than you might think.

Without he friction it most likely leaks at the pressure required to make it work-in theory that is.

[Sticky_Tape]

I think this is a better idea just a little more complex

[judgment_arms]

I think this is a better idea just a little more complex

Spudchucker, we get the picture, you like you design.
No offence but I’m beginning to get tired of it popping up all over the place: in your topics, in other peoples topics, the local news, swimming in my Coke, at this rate it’ll start popping up in my dreams, or nightmares as the case may be…:D

[Sticky_Tape]

I think this is a better idea just a little more complex

Spudchucker, we get the picture, you like you design.
No offence but I’m beginning to get tired of it popping up all over the place: in your topics, in other peoples topics, the local news, swimming in my Coke, at this rate it’ll start popping up in my dreams, or nightmares as the case may be…:D

You don't have to get all ralled up about it I don't even think it was in too many posts was it? maybe 5.

[Brian the brain]

It will fire one shot and than the pop-off will remain open..pfffffff

And the cycle stops.

I tried this thing over and over again and failed every time.


Marks MMG broke shortly after that thread..