Some round/weapon combinations are really prone to set back and resulting high pressure catastrophic failures - Glocks in 40 are a prime example. I almost never run a round back into the chamber if it has been chambered once and removed. As a rule, this should NEVER be done with an AR platform, as there have been problems with the light strikes of chambering desensitizing the primer. A serious pistol should never be unloaded except for maintenance; if you have concerns because of kids in your home, wear it on your person. If you have to remove a round from the chamber for some odd reason, it goes in the training pile.
I almost never clean a firearm unless I have been shooting or will be storing for a long period. Gun cleaning is not something that should be treated as a sacrament; most folks do it too much and it serves no good purpose. Again, this is especially true of the AR platform. If you have learned the white glove approach, pay someone to head slap you until you recover. An AR might need parts inspection every 5K rounds, but it surely does not need cleaning that often. Run it wet. I've seen ARs with 20K+ rounds that have never been cleaned, and have never malfed. (A failure in the cycle of operation is a malfunction - jam goes on toast.) 10 minutes with some SLIP 2000, a couple of paper towels, a couple patches for wiping small places, a bore snake if you are too anal like me, and some SLIP EWL in the right places, and your AR should be good to go for another several thousand rounds with just added lube.
When I got my issued G21, I ran a few rounds of ball and a bunch of duty ammo through it. Over 700 rounds in a few days, and I never cleaned it until I was done. If it had malfed from being dirty (as opposed to to dry) in so few rounds, I would consider it defective. I've done similar with a 1911 (A Yam 10-8 package on a Springfield) and a Wilson KZ-9. Same analysis.
