Handguns--An WW2 vintage canvas bag holds staple gun, tape, muffs (I come with my own eye protection) pasters, notebook & pencil, coffee can for policing brass, Necco wafers, targets, magazines/speed loaders, Bore snake and ammo (factory boxes if factory loads, MTM plastic boxes if hand loads.) A padlocked MTM pistol box also fits in the bag, fulfilling the CA State law regarding transporting in a locked container.
Shotguns--in 25 shell boxes, to be dumped in the pockets of a shooting vest or shell bag, depending on the weather.
CF Rifle--most everything fits into a Fat 50 ammo can which I also use as a rest, with a surplus Bergen pack for protective padding.
RF Rifle--a box of 50 fits in the pockets of my blue jeans and, with a roll of Necco wafers, call it good.