After shooting and when it's time to go home, I take off the barrel or barrels and run my Tico Tool through, which removes all the loose burnt carbon. The Tico Tool looks like a giant pipe cleaner, and I keep one in the trunk of my car. Then I spray some Breakfree CLP onto the oiler (like a mop for a cleaning rod) that comes with the Tico Tool and pull the oiler through the barrel from the muzzle to the chamber. The oiler has enough spray on it that some drips onto the ground when it squeezes down to enter the barrel (which is off the gun). Then I lay the gun and barrel(s) flat in the case in the trunk of my car. All this takes about a minute extra.
When I get home, if it's the Rem 1100 barrel, I use a special wire brush on the gas cylinder. I run a patch through the barrel to remove the excess lubricant and loosened crud (don't want it running down the barrel into the action or the wood). Then I wipe the exterior metal parts with a patch or cloth moistened with Breakfree CLP. All that takes is another minute. Then into the safe.
When I take the gun out of the safe, I run a clean patch through the barrels to make sure that there is no wet lubricant in there (or spiders or whatever) that could build up excess pressure.
On the Rem 1100 I will clean the magazine tube and action bar assembly regularly.
Just an ounce of prevention regularly applied