So I'm not some noob who just got one before you ask, I've had one maxed for months and got a second that I'm close to maxing but the more I use it the more I'm like "why am I using this again?" There's 3 places it really shines devil walker, sepiks, Goliath tank. Otherwise you gotta be a great sniper to use against mobs and get the 3 Crits and sometimes even that doesn't work cuz someone takes your kill or enemies have shields so the crit doesn't register. Honestly I realized after all this time that the LDR on my Hunter is far superior. High fire rate, good stability, super fast reload with outlaw, big mag size, a lot of ammo. Etc. black hammer honestly pales in comparison to most snipers with a good perk roll even if you're a headshot master.
Ps if you're not using all ghorns on Atheon I guess black hammer. But I personally just melt him in a second with a team of 4-5 ghorns
Personally, the way I saw it is if your accurate with your shots Black Hammer excels at PvE. Archon Priest and Phogoth are just a stagger-fest with it. BTW nice LDR