Hi there!
In the rule book pg 359 "Damaging a Horde" it is said that weapons that inflict explosive damage (like bolters) gain one additional hit against hordes...
so it means you take a single shoot and roll 2 damage rolls...that`s clear, but what about full auto? 8 hits ( 4 hits + 4 times from explosion)?
and what if you load your standart bolter with metal storm rounds and fire on full auto? Blast (2) said it hit a horde two times...
so does it count as 1 hit from standart damage + 1 hit from explosion + 2 hits from blast multiplied with full auto (x4) meaning you hit the horde for a damage of 16(!) to the magnitude ?