The type of inflatable that can sail 100 miles into blue water is not the sort that can be sunk by an airgun.
Indeed, but I had been under the impression (perhaps incorrectly) that the inflatables came off a larger ship and did not sail out 100 miles from shore.
Nope, but a .302 could sink it.
I'd think they had some trawler that they launched the rubber dinghies from.