I have a solar hammer with increased reload speed when mag is empty and the surplus perk. I'm not rerolling it for anything. It's the same perk the corrective measure has and gives you an extra mag of heavy ammo when you pick up heavy in crucible. Plus, the reload speed is ridiculously slow so the second perk is quite useful as well. I think I got extra lucky. I didn't reroll once, it dropped with those perks.