Blood Pack Punisher SMG: Submachine gun with a secondary barrel that fires armor-piercing rounds.
The Punisher features a secondary barrel that fires one armor-piercing round per main-barrel burst. It was developed by Blood Pack gunsmiths who found that their vorcha recruits frequently forgot to optimize ammo loads in the heat of combat. This configuration makes the process automatic and highly effective at penetrating armor.
Adas Anti-Synthetic Assault Rifle: Electrical weapon that's effective against shields and synthetic targets.
Named in memory of the quarians killed in the Morning War on the planet Adas, this weapon's electrical attack has been optimized for medium- to long-range firefights. Alliance marines take issue with calling it a "rifle" since, technically, it has no rifling in its barrel. The quarians shrug this off, as quarian weapon terminology rarely translates flawlessly into human languages.
Those are the two new ones, and the Indra is the "limited" promotional weapon that was previously only open to PC users who went to Alienwares page to claim a code around the time the game launched.