Found out about this I was like DAAAMN, I'm bringing that gun BACK! – Fires projectiles with Explosive properties.
Usage & Description
The explosive projectiles fired by this weapon deal 1.8x the listed damage, for a total of 6.0x critical damage (paired with the inherent 4.2x damage for Jakobs snipers). The explosion which occurs when a projectile hits a surface with an added hit-box or a normal surface can be used as means to dispose of multiple hostiles, due to the explosion's splash damage.
In the first weeks of Mr. Torgue's Campaign of Carnage, there was some unrest in the community due to the fact that the Cobra, prominently featured in the trailers for the DLC, was seemingly absent. In a forum post, Gearbox employee Hellface clarified that the Cobra is in fact in game, as well as revealing the drop rate.
Every time one of Pete's burners drops a sniper rifle, if that weapon spawns with purple rarity then it has a .88% chance (not 88%, but 0.88%: that's 88 in 10,000) to be the Cobra. This makes Cobra one of the rarest drops in the game.
For purposes of calculating damage modifiers the rounds fired by Cobra count as explosive but do not count as grenade damage as Torgue gyrojet weapons do. Therefore damage can be boosted by Axton's Duty Calls but not by Steady for example.
The Cobra was a legendary sniper rifle featured in Borderlands. The flavor text quote is presumably stated by Tiny Tina, and references its return to Pandora in Mr. Torgue's Campaign of Carnage.
The explosive icon on a weapon's item card is a standard texture sprite which is featured on all Torgue and explosive rocket launcher item cards. Since the Cobra is manufactured by Jakobs it has no sub-line to display the sprite and its item cards will not feature the explosive icon.
The Cobra is one of only a select few elemental Jakobs weapons. The others include the Greed, the Stinkpot and the Twister.
The Cobra is the third weapon from Borderlands to be featured in Borderlands 2 with a different rarity and manufacturer, the first and second being Sledge's Shotgun and the Bone Shredder.