Hello everybody. I'm 17 from Kosovo. I'm far away from any chance of having firearm, but I really wish to have one. I've made a home made single shot pistol. I found a fine steel pipe-inner diameter 8mm, wall thickness-4mm. It kinda reminds me of 357 sig barrel. The gun uses pyrotechnic ignitor and 3 ni-cd batteries. It looks like HK usp compact. Currently I fill it with 1/3 home made black powder(perchlorate instead of nitrate) It penetrates more then 5cm of wood and the recoil is much stranger then glock19. It hurts after the shot. I plan making desert eagle also and a bayonet rifle. My question is how do I find out how much powder is safe. I cant get any data on internal ballistics. Sons of guns on discovery doesn't show any real gunsmithing at all, its a worthless show. Here I may go to jail if I create a device with uses combat ammunition to produce wounding effect(cant remember the exact definition) but if it doesn't use ammunition its not considered a weapon. You guys have the experience so Ill be grateful for any advice.