Lighting Rod bug?

[texanincanada]

Not sure if this is a bug or not but when I use Lighting Rod about 2 out of five times it misses everyone in a group and it will do this usually two times in a row and then be ok for the next three or so. I know it will miss some of the group and I'm ok with that but when you have a group of ten or more and everyone is missed something seems off. Anyone else having this issue? My accuracy is 1.8. 

It also make zero difference what level the mobs are it misses Level 8 mobs as well as level 54 mobs.