SpudFiles

Hi
Ok, so a few weeks ago I had a go with a carbine black powder musket at a game fair. I found it great fun so thought it would be good if I could make my own pneumatic version so I drew a design as you can see below. My design is built around a coaxial concept with two valves both schrader, one for filling and the other for firing. The firing valve will be triggered by a hammer made from wood, aluminium or cast pewter with a pin on the end to trigger the schrader valve. The stock will be made out of natural timber, possibly oak and the barrel will be aluminium with a body made out of ever PVC, brass or aluminium of similar diameter. The piston will be made from turned wood or possibly aluminium with a rubber piston seal. The body of the gun will be attached to the stock by soldering two nuts on to it and then threading bolts through the stock. The piston is non serviceable like on most pen guns.
So I have just a few question about my design first do you think this design will work and how could I improve it? possibly by adding a face seal over the barrel where the piston meets it? Do you think the schrader valve adapter will thread in to a metal body and with the help of the miracle that is epoxy and be able to withstand 200psi air pressure? Is there any way I could make the piston serviceable without compromising on the sleekness of the design or if not how could I make the piston last for longer?
Any help would be very much appreciated, and I have a pen gun project that I have CAD models for that I will be posting soon.
Regards Gabriel S

I like it.

You will need some sort of bumper system for sure! Otherwise the back of your piston will get destroyed, and possibly the fill schrader valve will get knocked so hard itself will be destroyed or the hole it is inserted(threaded) into will get ovalized and cause a leak. The plus side of a bumper is, if you use the right material it will also reduce the pilot chamber volume, which will be essential if you plan to fire it by simply slamming a hammer into the pilot schrader valve.

Otherwise - cool design, and very nice minimalistic approach - it will look very nice when done!