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Co-axial automatic loader?

Posted: Tue Oct 10, 2006 2:46 pm
by BT1969
Has anyone here built a co-axial auto loader yet? I just thought of it this morning, and will build it if it has not been done yet. Of course it will be on a small scale for the first model.

Posted: Tue Oct 10, 2006 3:40 pm
by boilingleadbath
We would like to see your design, if you don't mind.

Posted: Tue Oct 10, 2006 7:20 pm
by Atlantis
I can think of a few ways to get a magazine to the barrel. A tee in the chamber matching up with a tee in the barrel. Make a gap in the chamber so part of the barrel sticks out, then reroute the chamber around the barrel tee.

Posted: Tue Oct 10, 2006 8:47 pm
by BT1969
Atlantis has got the idea. I will get a drawing made up with the general idea. How do I post pictures? (I'm sure this has been covered elsewhere, so feel free to post a link to another thread on it if need be. In the mean time I will search for such info.) If it is easier, I can just email it to someone to post on here.

Posted: Tue Oct 10, 2006 9:53 pm
by MrCrowley
go to photobucket set up an account and host it there and grab the [IMG] url and paste it in a message here.

Posted: Tue Oct 10, 2006 10:04 pm
by CS
Believe it or not I have actually built such a gun. Using both a tee in the chamber and the barrel. I never got the piston to work, so that is at which stage I stopped. Ill snap some pics tomorrow or the day after that.

Posted: Wed Oct 11, 2006 1:03 am
by BT1969
Ok, the parts are as follows:

red = chamber and upward T to allow magazine to stick out
green = barrel and upward T for magazine
blue = piston
black = exhaust valve
violet/pink = schrader valve
yellow stripe in piston = equalization hole through piston

Image


Pimpmann22 - why did the piston not work? Did it not seal against the breech of the barrel? If so, did you try bracing the breech with atleast 3 bolts coming in through the wall of the chamber?

A primary schrader valve may be needed on the camber side of the piston also. I was thinking that filling it from the exhaust valve side of the piston would help seal it quicker than from the chamber side. The rubber membrane on the face of the piston would have a loose flap over the equalization hole which would act as a one way valve.

For sustained fire, an air chuck would be used for the air chamber on both sides of the piston (insead of schrader valves), and the exhaust valve would be cycled for semi auto, and the air chuck on exhaust side of the piston (in chamber wall) would have a valve to shut off air flow to this area, in order to keep piston open for full auto fire.

Selective fire could be easily controlled by using 2 electric valves. 1 for the air line going to the back side of the piston (in order to close it). The other vlave for exhausting the air in the rear of the chamber, which unseats the piston from the barrel.

Yes it would be connected to an air compressor for auto fire.

Mr Crowley thanks for the photo hosting info[/img]

Posted: Wed Oct 11, 2006 9:56 am
by )DEMON(
Here is a similar design I came up with a while back: http://spudshot.com/Forum/viewtopic.php?t=82

It has similar loading of a single shot bb gun but is designed to be fully auto.

Posted: Wed Oct 11, 2006 10:57 am
by Brian the brain
I was thinking more around the lines of....

Posted: Wed Oct 11, 2006 11:33 am
by )DEMON(
I was thinking more of something like this............
Quite simple, it is an adaptation of my previous design.

Posted: Wed Oct 11, 2006 12:05 pm
by CpTn_lAw
that is a very interesting design..... :!:

Posted: Wed Oct 11, 2006 1:12 pm
by BT1969
Some nice pictures above, I will have to wait for photos, before I can post anything that looks good. Eventaully, I would like to post video also. Any ideas on how to get it from 8mm to a computer?

Now, has anyone actually built and tested one of these designs yet?

Also, for auto loaders - has anyone tried using the vented exhaust air to feed ammo?

Posted: Fri Oct 13, 2006 1:06 am
by Yonderknight
Hey Demon, I think a problem in your designs is that during the firing stage, the piston is pushed back and it allows ammo to fall back into the barrel. Also air can escape through the ammo clip. Unless you want the gun to be fully auto.

I think BT1969's idea is the simplest for single shots.

Posted: Mon Oct 16, 2006 7:40 pm
by THEMOST
Why would you need a ram rod or anything??? :?: Since there is no explosion in the barrel like real guns, there is no reason to seal off the breach.

I know from experience and it works flawlessly. The best way to do an auto reload system is to find a T joint that is flush to the inside of the barrel. Connect the crap together and drill two holes at the base of the T joint that is just the right size for one unit of ammo to fall into the barrel. Stuff an ear plug half way up the hole and tape it in with duct tape...I love duct tape...Put a screw on cap to the stock so that it is sealed for firing.

With an electric solenoid valve you can get like 10 shots without reloading the air chamber.

It doesnt make any sence to seal off the breach every time!

Posted: Thu Nov 16, 2006 12:55 am
by pyromanic13
)DEMON( wrote:I was thinking more of something like this............
Quite simple, it is an adaptation of my previous design.
cool idea demon almost reminds me of the method with a hammer in paintball guns but not quite very interesting...