My cheap crossbow broke, so I decided to make a wooden one using the left over parts (limb, trigger mechanism and foot stirrup) that could fire marbles or ball bearings by having a top barrel so the bearing doesn't jump out.this is my first instructable and im also writing this in hindsight; meaning i've already made it. this is more of a guide to the layout not strict instructionWARNINGIf you plan on making one of these you should treat it as a normal crossbow. NEVER POINT IT AT ANOTHER PERSON OR LIVING THING!I made this for target practice and for fun but a ball bearing could be potentially lethal! obviously bear in mind that power tool and hand tools can cause harm so work safe! I take no responsability for any damage or injury sustained by making and using one of these!