Unfortunately not, i was in the process of making one, but it would be rather stupid to basically say
if weapon is m4 warn
if weapon is g3 warn
if weapon is m4 reddot warn
if weapon is m16 acog warn
I was thinking of restarting development by doing something more like
if weapon is not m16 acog warn.
which would make it unigame.
Marty, there's already a plugin, i think. I'm fairly sure it's called antinoob.
3x grenades, that would be difficult, if not impossible, since the game doesn't distinguish between (in the logfile) 1 grenade 3 kills and 3 grenade 3 kills. So you could have someone warned, or spammed because of this.