Long-barrelled gun (5)
I believe the answer is:
rifle
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">long-barrelled gun</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for rifle that I've seen before include "shoot?" , "Gun - steal" , "Ransack; a weapon" , "Plunder - ransack" , "Long-barrelled weapon, normal army equipment" .)