I notice this happens most often when you have duel ppc on arms with lower arm actuators. Many times I am right on target to to see my ppc volleys go right past my opponent and intersect harmlessly behind him, not resistering a hit. Very frustrating.
Yeah, I noticed this for 5-6 games straight. I had to scrap my PPC Quickdraw because I couldn't hit anything, and even when I did hit the damage only registered a third of the time.
I fired at a Blackjack 800 meters away, he was powered down and my reticle was dead on target. Each PPC bolt went wide, with my left PPC passing his left side and my right PPC passing his right side. The spread is so bad that I hit a stalker and one bolt hit his upper left arm and the other hit his right leg.