Ouch.

code/modules/projectiles/projectile/beams.dm

@@ -107,8 +107,8 @@
 /obj/item/projectile/beam/pulse/heavy/on_hit(atom/target, blocked = FALSE)
 	life -= 10
 	if(life > 0)
-		. = -1
-	..()
+		. = BULLET_ACT_FORCE_PIERCE
+	return ..()
 
 /obj/item/projectile/beam/emitter
 	name = "emitter beam"
@@ -207,4 +207,4 @@
 	. = ..()
 	if(isopenturf(target) || istype(target, /turf/closed/indestructible))//shrunk floors wouldnt do anything except look weird, i-walls shouldnt be bypassable
 		return
-	target.AddComponent(/datum/component/shrink, shrink_time)
+	target.AddComponent(/datum/component/shrink, shrink_time)