Out of the an entire month of doing strikes and PoE maybe over a hundred total I've only seen it once. Until the other day when it dropped for me out of PoE 28. Re-rolled outlaw/smallbore/reactive reload. I was never hunting for it, it just so happened to drop and I've heard of it so I knew what I had. I say that because the more you hunt for specific things the more disappointment you will feel. Just gotta let it go and have fun with what rng gives you.