In my opinion black hammer was only ever good on certain bosses. The problem with it was you could shoot forever at those bosses without ever having to reload. Look at it this way for those bosses black hammer will still be the highest dps sniper with 18 continuous shots. Add increased special ammo armor perk to that. I don't understand the icebreaker nerf though the sniper isn't even that good anymore compared to other snipers.