Tried backpack with 2-gun plastic case in it and a 4-5 guns plastic case with accessories in a separate bag; decided that the way to go is small range bag with two guns in rugs in lockable side pockets, and if more is needed - in lockable pouches in the main compartment. Headphones, glasses, cartridges, loader etc. should fit there too.

Name Price Length Width Height Notes
Gunmate 1919687 Black $32 16” 8” 7” great; buy another?
Osaged River Tactical Light Duty $43 13.5” 10.5” 7.5” too small? try! zippers snap off? bougth ;)
Osaged River Tactical Standard Duty $50 18” 13” 10” too big
Maxpedition Compact $142 13” 10” 8.5” expensive; no lock loops?
Vertx COF $198 18.5” 10” 10.75 expensive; too big