First Combustion Rifle/Cannon

[wolfgang22]

Hi all,
this is my first post on this site, so I apologise if I have done something wrong or put this in the wrong place. I have built a couple of extremely simple pneumatic cannons (for bait launching) before but never a combustion cannon before, so I have a few questions. The first of which - would a long, thin chamber under the barrel work? I had planned on building a rifle rather than a cannon, and wanted it be bullpup with the chamber much like a pcp air rifle, under the barrel for shorter overall length. If this is not feasible I'll try to model it after the AirForce Candor,. And my second question - how do I build a simple bolt/breech? I have seen some quite neat ways of building them on the forum but they are far too difficult for me to build . I will be shooting heavy nail darts, and wax slugs from a 1/2'' barrel if that helps...

[farcticox1]

first one I ever made just has a sleeve over the barrel


You might need more of a slot for nails though

[jackssmirkingrevenge]

Welcome!

I'll make the point that a smaller caliber combustion is likely to be a disappointment in terms of power, the smaller the caliber the more pressure you want and a combustion cannon is limited in this area.

[wolfgang22]

first one I ever made just has a sleeve over the barrel


You might need more of a slot for nails though

thats a pretty sweet looking rifle/cannon there Facticox1! I'll definitely just use a sleeve over the barrel. Thanks for the advice Jacksmirkingrevenge, I'm just trying to build a low powered rifle for putting little holes in things out the back . High powered launchers coming soon...

[farcticox1]

This is what the whole thing looks like


Have progressed a bit since then, still using a sleeve over the barrel though