I have problem similar described here Projectile collision not working until Root removed from Components - World Creation - Unreal Engine Forums
and here Projectile collisions not working with arrow component as root - World Creation - Unreal Engine Forums
and here How to rotate collision capsule for any actor? - Blueprint - Unreal Engine Forums
When collision is not root - its don
t work correct. Projectiles flying through walls. If i set collision as root with the same settings then it`s works correct.