Metallic IPA off flavor

So I've searched the forums, and everyone seems to complain about having a drinkable metallic taste in what is generally a porter or stout. Plus I didn't want to bump a thread from 2008 so I just decided to ask.

I went to bottle an Imperial IPA last night (going to be my last time bottling thank god), and it didn't smell right. I tasted it an it had that "metallic" flavor to it, but it was not subtle, it was very prevalent. I know stuff can happen, but this is the 2nd time in a row, making that style, using my conical fermenter, that I have made an IPA with those flavors. I have made batches in my glass carboys, including IPAs, without issue. The first batch, I dry hopped, and thought maybe something got in there, so I specifically avoided that this time around with no luck.

My conical is a 7.3 stainless stout tank with the tri-clamps, both beers had over a pound of hops, the last one being 8 different ones, and my yeast was pushing the use by date. I am very much on top of keeping everything sanitary. I don't think my conical has any scratches, I figured older yeast would just take more time in the starter, and I cant see any hop combination causing such a bad taste.

I was hoping someone smarter than me could shed some light on what might be the issue, I've been at this brewing thing for a while now and am completely stumped