Here is one idea, more will follow.
The best outdoor bags of all purposes:
I have the Field Bag, an over-the-shoulder grab-all that will house a take-down rifle (as long as the components don't exceed 16" each), comfortably carry ammo, has water-bottle pockets, and the shoulder-strap is long enough to carry the bag as an on-the-back haversack if you are small of stature.
The strange pattern is not part of the bag. It is due to a low Western sun coming through my glazed front door and refracting onto the bag.
The interior pockets under the main flap will take a 4" Heavy revolver, such as a S&W "N" or Colt Anaconda or maybe one of the shorter-barrel Judges. It will, of course, carry a full-size auto pistol. The canvas is VERY heavy and nothing prints through.