I hate that show doomsday preppers. All they are fat creepy people who brainwash their kids and run around in military surplus gear with guns. Plus they failed survival already because know everyone know they will have supplies.
Besides its pointless to have a gun because eventually you will run out of ammo either from hunting or over time. You can't make bullet from thin air. You need to make the powder from stuff like sulfur and pepperflakes, you need to make the primer, you need metal to fill the primer, you need lead to make the slug, you need to keep your shell casings. Also you going to need tons of fresh water to keep you hydrated and for crops unless you want to use dirty water, people are going to hunt anything that moves for food which could result in overhunting and depletion of local wildlife. Your supply of twinkies, hotpockets, soda, junk food will spoil eventually.