Are the player and gun models seperate? Or is it like a first person POV with only the gun visible out in front?

Also, are the bullets sticking to eachother in the air, or are they "stacking up" as they impact the wall? If they stack up on the wall, simply code the bullet to stop when it hits a wall and become passable. Stop the bullet BEFORE it becomes passable or it will just continue to move through the wall.