Granades make me lagg

I have a problem,
All the special kinds of granades and normal kind of granades make me lagg.
What happens: when i start shooting when a granade pops up it actually start firing single shots at a low rate. What happens i get killed....
I always play on a wireless network but i sit right next to the router with one of the best onces available and my network speed is always the highest possible. My ping is around 25-50. So why do these granades make me lagg and how can i solve this?