I have mini dice that I bought in packs of 32, and roll groups of weapons with like-colored pairs of dice.
For example, the Nova Prime....If I fire 6 ER Meds, I roll six pairs of dice( one blue pair, one red pair, etc...) I just state which colored dice are for which weapons and roll away. To minimize confusion with my opponent, I usually roll several groups separately so week can keep track of which weapons hit and miss. Sounds complicated I know, but it really works with repetition.