Beacon Laser

I am trying to make a gun that shoots a laser. My plan is to have a beacon shoot at the target with a small explosive projectile unseen in the center, so it looks like the laser exploded in said targets face. but i have two problems; how to make a beacon sideways, and how to make an explosive projectile without it exploding in your face? if i do explode when hit a block, it counts air block as a block, so it blows up in your face. If i do explode when hit player, the missile is coming from you, so either it explodes in your face, or it hits a block and does nothing, because a block isn't a player. In a nutshell, how to make a Ghast fireball, and mainly, how to make a sideways beacon?