Early in the lifespan of Modern Warfare 2, the M93 Raffica had extremely high penetration, and could punch through almost any surfaces.
Due to the fact the Raffica fires three round bursts, and has a 20 round magazine, the final burst is only two rounds. This can be rectified with Extended Mags, which increase the magazine size to 30.
The Raffica has been nicknamed the "Pocket-FAMAS" and "Mini-M16", due to the fact it is as dangerous as both weapons, even at long range, and fires a three round burst.
The Raffica is extremely popular with the Akimbo attachment due to the fact that it has tight hip-fire, especially when coupled with Steady Aim.
Campaign Special Ops Multiplayer
Screenshots
Video
The above video shows a modified Beretta M93R firing fully automatic.
The above video shows the M93R firing three round bursts, with the stock attached to decrease the recoil.
Weapons 
Campaign
Special Ops