When I attended the Infantry Officer Basic Course (IOBC) at Fort Benning (1971), we were not assigned our own M16 but drew one any time the instruction required. They would bring rifle racks on the back of a 2 1/2 ton truck. You filed by and were given a rifle. We did not clean them after the instruction. The took the rifles in their racks and dipped them into a tank of lubricant.
You learned to bring a roll of paper towels when drawing weapons. First step, very carefully take the rifle. While pointing the rifle down in a safe direction, pull back the bolt while pouring a quart or so of lubricant out of the bore. Safe direction meant be careful not to get the lubricant on your buddies. Use at least half a roll of paper towels to clean the rest of the rifle.
About 125 officers each firing about a thousand rounds, do not remember a malfunction in the entire company. I would not treat a personal weapon this way.
You should remember that much of the Army’s method of lubricating and storing small arms has to do with inspections. Lubricant attracts dirt. Dirt attracts failing inspections.
When my dad was a state trooper sergeant they had an inspection of the troops. After cleaning and detailing the cruiser, polishing all his brass and leather he was all set. As a finishing touch he scotch taped a sticker on the rear bumper of the patrol car that said "How's my driving? Dial 1-800-EAT-$HI+". The lieutenant laughed his butt off.