SpudFiles

Hey guys, I have always wanted to build a small but strong portable hybrid, so My idea was to make it like Fnord's Hybrid and use a vertical piston so make it faster and easier to use. So I will be making it with Sch 80 steel, and probably a 2" main chamber, and a marble barrel. because I wanted it to be portable I was thinking if there is a way to create the same effect somewhat but just use oxy-propane and just have an oxygen cannister as well as a propane. Im quite confident this is safe in small proportions I am just not sure exactly what small is.

Thanks, Andrew

Unless you have a lathe or milling machine, the type of piston I used on the first version will be a pain to construct in a way which won't be damaged. A barrel sealing piston will be much more reliable. In fact, I haven't really had any trouble with the second version after over a hundred shots, other than what resulted from not knowing what I was doing (no bumper=cracks).

If you're only going to be firing marbles you can use a much smaller chamber.

Apparently oxygen is too expensive for the benefits it gives. I think SB15 has used it, so you'll want to talk to him.

Edit: I just had a good idea;
If you want to try a spring-based piston, you should probably try using a plunger from a bicycle pump (preferably a non-floating oring one). I bet that would work and also not be a pain to machine.

I don't full understand the concept of your second gun, Sorry.

It works the same as any barrel sealing pneumatic works, only instead of lowering the pressure behind the piston by venting a pilot volume, you raise the pressure in front of the piston by igniting the mix.
Both methods will open the valve.

You can theoretically use any barrel sealing pneumatic as a hybrid by adding a spark gap, but only guns made from strong, non-brittle metals will survive hybrid mixes safely.

_Fnord! don't forget the copper and aluminium..

Oops. brainfart.

Not many people make hybrids from copper/aluminum so it probably wouldn't apply to him anyway. I'll edit it though.

Okay, well the way I understand the piston is off the chamber instead? Im sorry but that is all I get, I have no idea as to how a regular piston would move back from more pressure in the chamber.