From what I have seen and heard (and read), the jointed screw together cleaning rods are the worst thing to use to clean your rifle with. I would recommend using electrical tape over the muzzle and having a "pull through"
(Otis,etc), to clean if necessary. The tape will keep most everything out even if you drop it. What you do have to worry about is if the gun is submerged, somehow, and water gets into the barrel and cannot get out because of the tape, you could have a catastrophic failure if you fired the rifle. Of course, if you happened to have a jointed (3 piece) rod, and the hunt was on the line, I would use it if there was no other alternative to removing a bore obstruction.
Certainly not to be used for routine maintenance, but last ditch effort to save a hunt would cause me to use one in the field (or wherever).
You can purchase a 5 piece steel rod for the M-16, that is in a short package, but should be long enough to clear the obstruction, if necessary. I used to carry one in my backpack, and had it taped with electrical tape to prevent it from rattling in the pack. Never had to use it, thankfully.