Abstract: A projectile launcher having a barrel for holding projectiles traveling through an aligning opening in or connected to a rigid support. Two bow arms extend from the rigid support. A bow string travels between the ends of the two bow arms and behind the aligning opening. The rigid support may include a brace which extends from the rigid support to the forearm of the user. A piston within the barrel or the barrel itself is propelled by the string. The piston moves relative to the rigid support which remains substantially motionless when used. This bow may have an arm brace characteristic of a wrist slingshot or other bow designs. Pulleys or cams of novel design having curved lips are attached to either bow arm to decrease wear on the bow strings. A novel pulley arrangement is disclosed which limits the number of strings passing behind the rigid support.