I just watched the NatGeo special, Bear Island, on netflix and spotted a ranger using what looked to be an oddly gauged H&R single-shot to shoot darts into brown bears. A little googling and, sure enough, they made a traquilizer setup with a 32 gauge shotgun and a tranq. dart adapter (powered by .22 blanks). Anyway, it was a pretty good documentary and rare enough to see such a firearm, so I thought I'd share it here.