SpudFiles

I have come up with this design for a simple mini combustion that is condensed into one long tube, perfect for rifle designs.

Pipe B is the larger of two pipes needed and acts as the chamber and barrel housing. Pipe A has the same External diameter as Pipe B's internal diameter (or as close as possible), so that A is free to rotate within B. A notch is cut into B for the bolt which is attached to A to rotate. While the bolt is facing up, two holes in A and B line up to load ammo into.

A screw cap is placed on the other end of B and spark screws are drilled into where it is shown on the diagram.

Firing sequence: Load ammo by rotating breech, spray in some deoderant, screw on cap. Press sparker.

I'm probably not going to make this, as its not really a hobby of mine anymore (money, car etc...) but I thought I'd post the idea in case anyone wants to adapt it for their own use.

does the barrel rotate or slide back and forth. i don't think you'll get too high of pressure build up in the gun because the bolt assembly will might leak but it is a mini so it doesn't really matter

Remember this is a combustion so leakage isn't as much of a problem but I know how snugly some pipes fit so with a bit of grease and maybe a bit of felt on the end barrel that slides in the chamber the seal can be quite tight. It isn't meant to fire any big heavy ammo.

My design has a rotating barrel but I suppose it can easily be modified to some sort of back and forth bolt with notches to lock it into position.

i think rotating would be better. my minis have proven to get pretty hot when i shot them and burn stuff in the chamber, so i don't think felt is a good idea