Here's an odd but helpful bug that I've noticed about pelting strikes (seraphim):
im using pelting strikes with the chance for multi-hit mod, after using pelting strikes with BFG, then swithcing back to a melee weapon,
the multi-hit effect works 100% of the time afterwards, at least until log out.
I'm playing on the PS3, so don't know if this will work on a 360.
steps I took:
1. having succession mod for pelting strikes
2. use BFG buff
3. use pelting strikes with BFG equipped
4. switch to melee weapon and use pelting strikes