Thingiverse and I are not responsible for damage or injury caused by the use or misuse of this TOY!! This is a model desktop cannon that really fires. You can drill the barrel or leave it the way it is. My Prints of this have been extremely strong but that could vary from yours depending on what Gcode generator you use and what your settings are. I recommend using your best judgement as to weather your print strength is adequate to actually fire this. I recommend using this as a conversation piece.Uses a SMALL amount of black Power behind a piece of cotton ball behind a BB behind another piece of cotton. Add powder to rear powder tray, ignite and amaze your friends. Please don't misuse this model it can be dangerous if pointed at people. If its misused I will not post my other MUCH cool designs of this nature. I'll put this one out there and see how the response it. I have designs for miniature cannons that use fuel/air combustion like a potato cannon, both single shot and revolver designs. Not sure if those are suitable for this site. Let me know if I should share them.