1) Beagle lead-in 2) Beagle letters 3) Beagle or Bounty preceder 4) Boat letters 5) Bounty initials 6) Bounty letters 7) Bounty title 8) Britannia letters 9) British destroyer designation 10) British naval initials 11) British seagoing initials 12) British ship initials 13) Designation for UK vessels Found on https://www.crosswordclues.com/clue/hms