Pill bottle and pen combustion with onboard fueling

[lewist123]

Hi all

First post on this forum, but not new to the world of spud guns.

I built a big combustion cannon about a year or so ago. it consisted of a fairly standard 4x18 inch combustion chamber, and a 2 inch by 5 foot barrel. unfortunatly after weeks of fun, the gun started to show signs of slight failure and as such it was decommitioned.

I tried to make a few piston air powered guns, none worked.

So a year on and back to the combustion guns again, here is my first mini type gun.

It consists of a pill bottle, probably 50 ml and a ball point pen tube. I have included an onboard fueling system that consists of a lighter and a length of hose going into the body of the gun.

about a 4 second press, or seven short presses gives just the right amount of gas, and currently i am using a remote BBQ sparker for the ignition.

It seams to work really well actually and can shoot the lengh of my garden (about 50 - 60 feet) although that is MAX range.

at shorter range it makes a nice mess of a spud pellet!

here are a few pictures









I have a short vid, but its not very good, so i may do a better one if people want!

Thanks

Lewis

[SpudFarm]

pretty cool mini.

haven't been much of those around lately.

[lewist123]

thanks!

i was quite surpised at how far it can fire!

as mentioned, i could probably get reasonable accurcy at say 20 feet.

i found that the type of spud makes a huge difference. the harder the spud the lesser the distance it fires! the little spud pellets seem to get stuck.

I am already thinking about my next one... i am thinking a hybrid of about the same size!

[TwitchTheAussie]

Ah the mini's. The high tech class room weapon. Sweet as mate :thumbright:

[lewist123]

well i made another today.

using another pill bottle the same.

Unfortunately it broke before i got pictures, but this time i made a mini hybrid.

it consisted of the same pill bottle, but i glued the pen tube further into the cap so i could screw the trimmed down top cap back onto the pen on the inside of the lid. I used 3 thicknesses of cling film.

I tried it as a stand alone combustion and worked well, so i then took it to 5 psi and got a big increase in performance and power. Then i went to 10 psi and the whole thing exploded. woops! luckily i was prepared for it and had a little screen in the way so i didn't get bits of plastic in my face!

i will have another go tomorrow with a more suitable combustion chamber!