Full auto bb gun

[PYRO500]

I have had the idea for a home made super rapid firing bb gun that has a vertical feed tube leading into the barrel some how with a compressed air sorce from a co2 tank led through a regulator and switched with a blowgun. any ideas on how to keep bb's from flowing all through the barrel in a device like this?

[mongo blongo]

I tried something like this when i was a kid!
I used a solenoid with a spring behind it (hooked up to the trigger). When the solenoid is activated it release the bbs and when you take your finger off the trigger the spring pushed it back into position stopping the flow of bbs. It worked quite well until my brother broke it! Bastard!
I would also suggest (if you haven't already thought of it) having some kind of container on top of the tube so you can fire a decent amount.
It may be worth finding out how this is achieved in paint ball guns.

[PYRO500]

A paintball gun does this by having a recocking bolt that blocks the barrel witch is nit feasible to improvise with bb's at a reasonable cost

[BoB-]

Magnetize a small pipe that will fit in the barell but a BB cant drop through. Glue/Weld this into place right behind the magazine, so as a BB falls into the barell, it does not roll backwards and the magnet keeps it from rolling forwards, acting as a plug until a burst of air releases it, and the next BB takes its place.

[This message has been edited by BoB- (edited September 11, 2001).]

[berg]

How do the small Mini-electric BB guns work? cold these be scaled up to be more powerfull? - Berg?

[twinkle]

maybe this can be of some help there is another homepage to but I could not find it
http://www.kutz.com/combat/bbgun.htm

[twinkle]

here is that other homepage I had to search for it .Although I know it is RC stuff it works and maybe it can be made stronger to.
http://www.mwci.org/members/rthibault/R_C_Warship_Construction.htm

[Anthony]

The problem with just releasing a stream of gas fed with a hopper of BBs is that when a BB is fired, another will drop down behind it while it is still in the barrel, blocking the force to the BB in front so that it no longer accelerates. So effectively you have short barrel (the lenght of which is decided by how long it takes for another BB to drop from the mag/hopper).

I think a bolt is the only way to gohttp://theforum.virtualave.net/ubb/smilies/frown.gif

Worth a note is that the Daisy 2003 CO2 pistol can easily be converted to fire full auto. It has a 35 round magazine (unusually high, especially for a pistol) and the slide blows back with each shot.

[PYRO500]

I think an interupter disk might work easily, just have a feed tube larger than thew bb's but not enough to let them get side by side then have a disk with a hole twice the size of a bb run through it at a variable speed. if I have time I may draw a pic.

[Anthony]

That's a good idea! Simple and effective - my favourite kind of solution.

I guess if you didn't want to waste gas you could also use the interupter disk to open and close a solenoid valve to release a pulse of gas for each shot.

[PYRO500]

That would be possible to do that However there would be a certain amount of precision required to time something like that effectively, also you would need a fast high pressure solenoid that could run off of low voltages witch I have yet to find even a solenoid valve that would work here, That's why I suggested the blow gun nozzle. If anyone knows where to get a valve to switch these kinds of high pressures and is portable please come forward. it would be nice not to have to use a regulator.
also does anyone know how much pressure a standard shop blowgun would hold back and be able to switch?

[PYRO500]

I just drew a pic of it (forgive the misspellings) as alway's you'll have to cut and paste it into a browser.

http://www.geocities.com/pyro2000us/bbgun.jpg

[BoB-]

If the motor in your pic were pnumatically driven it would mean less electronics.

[Anthony]

The only issue I can see is gas escaping into the hopper which would reduce power, but if the hopper isn't very big and you release a big burst of gas it shouldn't be a problem.

High pressure solenoid valves tend to be very pricey, cheaper hydraulic valves will work but they tend to be leaky when used with gas. The closest solution I can htink of would be to use a solenoid coil to activate a valve/blow gun.

Personally I'd just go with the blowgun (or high pressure equivilent) for the simplicity. Who cares if the CO2 bottle doesn't last so long?

With CO2 you might have trouble with expansion, i.e you drop the pressure in the bottle faster than the liquid CO2 can boil to replenish it. Resulting in a drop in bottle pressure and power the longer the gun is fired for.

This might be curable with an expansion tank between the CO2 bottle and the gun.

If this is a problem you could try gases like nitrogen or argon (latter easily available in dispossable bottles for MIG welders). The upside is that the bottle pressure is several times that of CO2, but due to it not being liquified you get less gas per bottle.

I'd really try not to use a regulator as the area of a BB isn't much and to get a decent level of power you really need some nice high pressure behind it.

Dunno about the max operating pressure of blowguns, but I's guess 150-200psi, that typically being the max pressure of garage compressors.

[BoB-]

On the side of the blowgun in my garage:

WARNING: This blowgun is meant to be used at a pressure no higher than 90psi!

It also says something similar on all my airtools, but I run 120 through all of them, I oil them daily and havent had any problems.

[skunkdude]

Anthony, how would one go about converting a daisy 2003 to full auto?

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"Fighting for peace is like fucking for virginity"

[Anthony]

http://armory.freeservers.com/html/daisy2003.html

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"Shit happens. Get a fucking helmet"

[PYRO500]

I beleve that model has been pulled from the market hasn't it?

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visit my web page at:
[URL=http://www.geocities.com/pyro2000us/]

[Anthony]

First I've heard about it if it has...

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"Shit happens. Get a fucking helmet"

[skunkdude]

i've searched the net, and i can't find any where which is selling these pistols, let alone in the uk. all the US companies i have asked say that "this model is unavailable" and i can't find a single uk site selling them.
are there any other air pistols which work on the same basis as the daisy 2003?

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"Fighting for peace is like fucking for virginity"