Ignis constructs [Ulduar-10]Follow

So my guild has recently gotten into Ulduar 10, successfully downing FL, Razorscale, and XT-002 (9-manned) in the two weeks (one day per week) we've been there. Towards the end of our most recent raid, we took a crack at Ignis (mostly as a learning attempt - we only had 8 on at that point and no ranged as our SPriest DCed).

We had a great DK tanking and breaking constructs, but it was readily apparent that we need someone ranged to blow them up ...

Two of our ranged DPS are hunters (neither was on during our attempt), but I was having a conversation with one the other night and he said that hunter would have trouble pulling off a 5k crit necessary to break the constructs. This leaves us with the options of (1) SPriest and (2) Resto Shaman.

The question for the hunter boards: is there some way for hunters to shatter the constructs that we're not seeing? Or are we just going to be limited on fighting Ignis based on who's on during a given night?

Tried as sv and failed :(
When we are in that situation we have the tank stand in the water to tank, the healers and ranged all stand on the wall on one side of the pool with the off-tank stood at the top of the ramp leading on to the wall. The constructs are then forced to run thru the OT to get to the raid making it an easy job for the OT to grab and keep aggro on them.
Then all just nuke Ignis as hard as you can.

It is very hard on the healers but it is possible to do him without shattering any constructs

Destro locks, Fire/Frostfire Mages, Laser Turkeys, and MM hunters all have at least one attack that can shatter constructs. We're far from the most geared, and our firemage has about a 95% chance to do it with fireball. Our GL is specced MM, and he has a lot of success with Chimera Shot.

Or you can tank him in the water. But that takes a fair amount of DPS to burn him down before enough constructs spawn that the MT becomes basically unhealable.