Sure, you have a stock of canned food, shelf-stable this and that, seeds, generators, solar panels and livestock, as well as the firearms and ammo to protect it, but what are you going to do if your gun goes down? Do you have what it takes to make sure that firearm can last you if the stores never reopen?
Step 1: Get a supportable platform
It is so cool to have that exotic, next level, brand-new gun that no one else has, right? Well what happens when that gee-whiz too-cool-for-school brand new gun breaks and there is no factory to send it back to, no gunsmith to visit, and no on-line forum to seek advice from. This means choosing something that has been around for a minute and was made in decent enough quantity to prove fairly common. Commonality means that you will easily be able to acquire parts and gunsmithing knowledge pre-SHTF.
In rifles, think of Ruger Mini-14s, Remington Model 700s, AR-15 style platforms, SKS\'s, AK-style platforms, Short Magazine Lee Enfields, Mosin-Nagants, Mauser K98s, M1 Garands, FN FAL designs, and so forth. In pistols, you want something like a Glock 17, Colt 1911, Walther P-38, and Beretta 92F. Shotguns think Remington 870, Mossberg 500, and Ithaca 37. All of these guns were made in the millions and even tens of millions.
This is not an all-inclusive list, just something to give examples. They have common calibers that can be obtained in quantity, often of military surplus already sealed in spam cans. If you look on CDNN\'s website for example, they literally sell every spare part for the Walther P-38 for peanuts except the frame itself. The total cost of all these spares? Less than $100, which is about a 1/4th the cost of a good used P-38/P-1. That\'s what I mean by supportable.
Step 2: Learn how to fix it.
Buy an armorers guide that takes the gun down to the bottom bare frame and back up again. It\'s best that this is not digital. If you have a paper copy, it will work much better when the lights go out. Take an armorer\'s course if possible. The CMP gives an excellent class on the M1 Garand at their center in Anniston every year. Remington often offers classes on the 870 and Model 700. Glock holds hundreds of armorer\'s classes every year. In these, they will take you from stripped frame to assembled working gun at a pace that you will be able to handle. Once you get this knowledge, practice it because it is perishable. Every year or so, so a complete disassembly, inspection and reassembly/function check.
Step 3: Have a stock of tools and parts
If you have that supportable gun and the skill to keep it working, stock up on a supply of spare parts. Get one of every spring, screw, latch, pin, and subassembly that you can. Put it in a sealed container co-located with the armorer\'s manual. Invest in a set of armorers tools for your gun. This can be as simple as a set of brass punches, a hockey puck (to rest the weapon on while being punched), a small hammer, and a few decent screwdrivers. Many manufacturers like Glock and SIG sell special armorer\'s multi-tools for a token fee. GET ONE.
Step 4: Share the knowledge
If you walk down this path, take someone with you. A friend, relative, or neighbor with similar interests that you may be sharing space with in a TEOTWAWKI situation would make the perfect set of spare hands and eyes when going through an armorer\'s school, or building an AR15, or rebuilding a 1911 from scratch.
You may not be around forever, but the information you can pass along can.