Rifle strap (5)
I believe the answer is:
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">rifle strap</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for sling that I've seen before include "Keeping afloat" , "Arm bandage; hurl" , "Chuck; support for damaged arm" , "Move off!" , "Simple weapon; throw" .)