Don't forget about a real combat shotgun like the Saiga 12
Watch up to the two or three minute mark at least. Some good shooting right at the end too.. you can get twenty round drums, or magwells that allow very quick magazine changes.
Choose the right shotgun for your needs. The Saiga 12 is an amazing shotgun.
G19 G26 G30 Sig 2340 357 Beretta U22 (kid's) Two Saiga 12 Two Draco 7.62x39 "pistols" Colt 6920 Saiga SGL21-94, M92 Krinkov "pistol," PSA Patrol Carbine Saiga 223