How to make custom projectile dispersion

in the entity management tab, there's a block called "Shoot ranged item as {Event/target entity} with power: [1] damage: [5] knockback: [5] type: [Arrow]" which fires the chosen projectile from the chosen entity. If your shotgun is a ranged item element, make a When ranged item used procedure and put a "shoot ranged item" block inside a "repeat [5] times" block. For a more accurate spread, first store the player's pitch and yaw in local variables, then every time a projectile is fired, alter the player's pitch and yaw by a random value. After all projectiles have been fired, set the player's pitch and yaw to the values that were stored earlier.

Hope you understand the jargon that I have typed.