37 replies to this topic

[sniper25]

I was thinking last night, is there a valve that can allow a full auto fireing mode, on a single barrel gun (not like the C.S.H.G). or is there a way to make one.

[ompa]

Not that has really been made yet. Of course, you could be one of the first to take an idea to completion, so get designing!

~ompa

[CaptainSlug]

Well, it depends on which propulsion system you're using. Also all of the full-auto systems will require motorization of some form if you want it to be any faster or more efficient than the pneumatic advancing systems in the wildfire, powerclip, or RF20.

Making an automatic spring plunger powered gun is insanely difficult because it's hard to find a motor configuration that has enough power to prime a powerful enough spring to get any range.

For an air tank system the problem is that firing darts will use up alot of pressure that you will need to replenish with a motorized pump. And in order to prevent the motorized pump from making the gun explode it would have to be regulated to keep the pressure at a specified safe level for the system in the gun.
And then the firing would have to be controlled with a solenoid (or similar style) valve.

It's possible, but requires some complicated engineering and a good understanding of what parts would be required to make it happen. There's no non-motorized mechanical system that will give you a fully automatic nerf gun that requires no priming of any kind because that would require perpetual motion. Something that only the dillusional think is possible.

Edited by CaptainSlug, 15 April 2006 - 10:52 AM.

[m15399]

http://www.nt3.idv.t...ch/ur1/ur1.htm#

The first barrel design on the first page is the one used in the gun.
The second is the valve, and how to connect it to PVC.
The third is the video.

A longer barrel and bigger PC should work as full auto.

[CaptainSlug]

That's not automatic though. It's just a salvo/shotgun shot because you can't control how many come out without having to load the amount you want beforehand.

Edited by CaptainSlug, 15 April 2006 - 12:29 PM.

[m15399]

Shot gun effect would shoot them all out at the same time. When you watch the video, the darts are spread out and it would look like auto to me if more darts came out.

[CaptainSlug]

They're only staggering because they have different friction and they're not all hitting the inside lip of the barrel the same way. If a group of darts are all propelled by a single pressure chamber release then it's a shotgun shot regardless of whether or not they all come out in a perfect line. In order for something to be considered automatic each dart would have to receive it's own propulsion, not share it with a group of darts.
Otherwise I could just stick darts end-to-end in a barrel and call it "auto".

Edited by CaptainSlug, 15 April 2006 - 01:48 PM.

[sniper25]

thanks for the help

[m15399]

That just depends on what you consider auto. That gun would work for my full auto purposes:
1. Mowing down large amounts of enemies
2. ...You mean there are more uses for auto?! No number two.

The difference between shoving darts in a barrel and calling it auto and the 3DBBQ design is the way the barrel is made. There is a reducer in BBQ's which makes the darts more spread out and less shotgunned.

[The Inventor Guy]

Yes, it can be done, and has been done. Only in prototyping though.
I wouldn't like to say too much so my design doesn't get stolen again, but fully automatic homemade nerf is out there.
There's a spring automatic system which does not require recocking by electronic or gas aid. There are a few gas automatic systems which include a hyrbid of spring and air or only compressed air for the operation. All systems can use cartridges, most work better without cartridges at the cost of extra length to the blaster.
If I end up completing some decent drawings on the computer of some designs, or feel like taking pictures of prototypes, I will post them. Fo' sho'.

I'm just saying it is out there, some people have done (myself included) but do not wish to show their creations or designs just yet. You too can create an automatic system, just dream, imagine and create. It's a simple process, but takes alot of thinking.

-Tidge.

[murakumo32]

Rip a plunger assembly off a WF or RF20 and invent a way to slap a clip onto it and get ranges in the high 1000's (over-exagerated).

[boltsniper]

It's all about energy.

With an autoloading system, whether it be semiatuo or full auto, there has to be energy available to cycle the action. With a pneumatic system you can use the pressurized gas to cycle the action and fire the round. With a plunger system it becomes a little trickier. The energy in the plunger spring is just used to fire te round so a supplemental source of energy must be used to cycle the action. In CaptainSlug's gatling he is using a electric motor to accomplish this. In airsoft guns they use electric systems as well. The RF20 uses compessed air for this task, while the dart is propelled by a spring/plunger system. Designing a full auto system is not that hard. Finding the proper energy source for both propulsion and cyclign is the hard part.

If you think about is separately like that, it may help you design a system to accompish it

[sniper25]

could you add a spring to a checkvalve to give it more of a holding force

chamber>ballvalve>checkvalve

[m15399]

Why do you need a check valve? That would only reduce the velocity of the air.

[sniper25]

so when you release the ball valve the check valve will open then quickly close.
then again im new and have never tryed this. so that problably would not work

[m15399]

I have no idea what you're talking about. How would a check valve close the valve? Are you sure you're talking about check valves? You might be refering to an over pressure release valve, which is sometimes called a check valve in modding.

[KnightValor]

Adding to what boltsniper said, its easy to design an electric full auto gun.

However, its hard to BUILD one. If you have any electric airsoft guns, take them apart some time. Its very simple on the inside. The problem is, you have to have the perfect mold for everything, high quality parts that won't tear, and some way to hold a massive battery (airsoft bbs are around .2 grams, nerf darts are about .5 grams), at least twice as strong as the one you used to run.

Another problem is shell ejection. If you are to use a clip, you will need a big clip for a full auto gun... At least 20 rounds, right? Well, you're going to need to use shells or your darts will be crushed and you will end up with more than one dart in the chamber... more like one and a half. But with shells, you're going to have to get them out of the barrel when the next round is chambered. That makes thing kind of complex there.

Yet another problem is safety... My last idea for a semi-auto gun (or... only one, actually... lol) was to use solenoids (electromagnets) to propel a plunger when one charge, and retract the plunger with another charge. It was an okay idea, but if I'd done more research I would've found that most solenoids require 12-36 volts and only move thing half an inch... Not the most safe system for a gun... and why would you risk your life just to shoot a nerf dart??


Yeah, if you have a plastic factory and can make any molds you want, go right ahead, make a full auto system based off airsoft guns, or something. But otherwise, you better have a damn big wallet and not mind constantly custom ordering plastic made from molds you will likely have to cut by hand in wax or something, unless you are very, very good with blueprints.

[m15399]

You do not need plastic molds and such. Doom has made one with the normal homemade parts. Don't be lazy! There are easier ways around everything.

[KnightValor]

Meh...


If you don't, you will instead probably get something
- more easily breakable (unless you would have used low quality plastic...)
- Heavier
- Likely larger
- more wear & tear
- more expensive once you start making alot of them (if its finished and good, you would be retarded not to sell them...)

[sniper25]

m15399, sorry i was talking about a regulated high pressure release valve

Edited by sniper25, 16 April 2006 - 05:29 PM.

[m15399]

Have you seen Doom's? It's not in the least bit fragile or heavy. Here's a pic:

Sorry, it's a bit big...

[KnightValor]

Whoa...


That's an awesome idea with the whole lever thing... Whoa. You could make a full auto one by just pumping a handle up and down on the opposite end. You could give yourself great mechanical advantage with a long lever, and...



Doom is officially my hero.



So, whats its rof, clip size, accuracy, range, and yadda yadda ya?

[sniper25]

what of you used a crank, like the old days. you could use a crank with gears to pull back the plunger and at the end the plunger would be relaese.

[Doom]

Just noticed this thread.

That's a really old picture from 2004. More recent images are available. Since then the system has been improved to the point where it is effectively semi-auto, that is, a system where a single action controls the clip and the valve. The system can be made into a full-auto system rather easily as well with a modification - the lever needs to be moving constantly. That can be easily done with a more powerful electric motor.

Also, please do not get the wrong impression from the design. There are so many ways to do this design better. My original intention was to use all of my leftover parts. I had noticed that 1" ID PVC fits and moves freely inside of 1 1/4" PVC and I got the idea to make a moving barrel that closes on the dart. What you see only is a demonstration of the technology.

Recently I had been modifying the design to use a Dr. Nerf-style pressure chamber, a large air backpack, an improved brass barrel, and several other changes. All changes should be easy once I get the time to do them. The system should be radically improved once those changes are made.

To answer a few specific questions: ROF only depends on how fast you can move the lever and eject the shell (ejection was done by gravity, which is somewhat unreliable). I have been working on a way to eject the shell automatically. The small clip I made could hold more than 15 darts if I remember correctly. The clip was a little unreliable because it was gravity fed, but that can be fixed with springs. Distance wasn't too great due to the old rubber tube I used and the ball valve, but that can easily be improved.

Before this thread I intended to keep this a secret during my improved version's development, but I suppose that won't happen.

[m15399]

Oops, sorry! There was already a thread about it (broken pics) so I figured you didn't care.