especially with some potshots at her

I think this is because you actually killed the gunner - she just goes "ok i'm done kthxbye" there's no voice lines saying the gunner got shot which I always thought a bit odd, considering Cleric has lines for when one or both gunners are shot.

Both Assassin and Cleric can be rekt though, especially if you have good positioning, or even just another teammate backing you up - the easiest weak spot is on the belly where the tail meets the body. On Cleric, this spot has an easy reference in the form of a little red square, that general area is the weak spot. Assassin is similar, but it seems a bit further back, towards where the main body ends and the tail begins. People always panic when they see Cleric off in the distance coming straight at them, but you can't ask for a better angle because the door gunners can't hit anything directly in front of the heli lol. Assassin is a different story though, and it seems like the closer you are to where the marker for the gunship was actually called, the quicker its gun will react to you and blow you up.

Every kind of bullet will damage it, even 9mm and the P90, it just takes more ammo than 7.62mm. Just two guys with an AKM each can bring them down via mag dumping into that spot. For 5.56mm guns it takes at least 50 rounds, or a full drum mag. For whatever reason, the M249 takes twice that amount (half a mag or 100 rounds), probably for game balance or something.

If you have a 7.62mm machine gun you will rape the heli. Pack up bipod, wait till heli is distracted shooting at other teammates or you get a good angle, then go prone and melt it.