SpudFiles

I am in the process of building a somewhat compact tennis ball launcher and would like to hide the mechaincal parts of the launcher inside the stock I have constructed. I cant seem to find the smaller propane cylnders some members have found, so instead of using a full size propane cylnder I want to make a resivor of some sort or a magazine if you will that I can refill myself. I havent seen anything like this yet as most folks seem to use a whole 1LB tank. I was thinking of cutting down a cylnder and welding it in the middle or something to that effect. Even a pipe nipple would work as long as I could get about 50 shots out of it. Some research has told me that I need a cylnder that is capable of delivering liquid propane like a camping cylnder or a non-OPD cylnder but thats about all I have found. The stock is 3" PVC about 20" long and has to hold a fuel source, power source, regulator, meter, and ignition. I have constructed a few launchers and this is more of a challenge as this is the first one where size is a concern.

Fitting all that in a 3" cylinder would be a feat. Does it have to go in that pipe, or could you build a casing around the components?

You might consider using butane instead of propane. The lighter refill cartridges are pretty small. Here's one being used to fill a syringe. It should be possible to plumb it into an actual meter system.

Butane cartridges are at much lower pressure than are propane but you'll get about the same number of shots per volume of liquid fuel and the energy is the same.

Similar to a Paslode nail gun. Excellent idea.