With what's coming, it's more critical than ever to be prepared. u/ObamasPinkSock wrote a great post on Cheap and easy ways to prepare for long periods of martial law or civil war without power or water.
So here's a firearm buying guide to help interested patriots better protect themselves and their loved ones. This is to save you time, money, and the risk of buying the wrong gun.
Affordable, concealable, transportable, and quick to deploy. Downsides are poor accuracy and range compared to rifles. Practical range is under 25 yards and it may take 3-6 shots to put down an aggressor. You also need more training to use a handgun effectively. Works well enough for home defense, concealed carry, inside a backpack, and cramped spaces like vehicles.
The best handguns are 9mm semi-automatics with removable magazines because they are easier to shoot and let you get more rounds on target than bigger caliber handguns. 9mm is the bullet diameter, semi-automatic means one shot per trigger pull where each shot automatically loads the next round, and removable magazines let you swap out a new mag in under three seconds for another 15+ rounds at the ready.
$200-$300 - Walther Creed (formerly the PPX)
$300-$400 - Canik TP9
$400-$500 - Smith & Wesson M&P9 M2.0 Compact w/o thumb safety.
$500-$600 - Glock 19 gen 5 (or gen 3). Popularity means ease of finding aftermarket accessories like holsters and ugprades. Recommended upgrades: Magpul Magwell and Tango Down enhanced slide stop.
Ammo: Bonded jacket hollow point bullets are best. Example is the 124gr Federal HST round.
Pistol Caliber Carbines
These look like rifles but shoot pistol (handgun) ammo. They're softer shooting than rifles, not as loud or concussive, and are easier to aim than handguns. The longer barrel also adds extra velocity for better terminal performance. Pistol caliber carbines are Ideal for smaller framed people who don't have the time to do the kind of training a handgun requires. Rails let you easily mount red dot sights and white lights.
$200-$300 - Hi-Point 995TS. Cheap but reliable. Magazines are limited to 10 rounds though.
$400-$500 - Ruger PC9. Can be "broken" in half for easy transport. Fits inside a backpack. Takes 33-round Glock mags too.
$600-$700 - Beretta cx4 Storm. High quality and reliable.
Ammo: Likewise, bonded jacket hollow point bullets are best. Due to the longer barrel, higher pressure +P rounds like the 124gr +P Federal HST are more suitable here to get extra punch.
AR15 Rifles/Carbines in 5.56
Best all-around firearm if you don't need concealed carry. You get 30-round detachable magazines standard (except in commie states), accurate fire out to 600-700 yards, great ergonomics, rails for attaching optics / lights / grips / backup sights, adjustable stock length, versatility and modularity, and light weight compared to most rifles.
Suitable for home defense, hunting (check laws though), neighborhood defense, marksmanship training, tactical carbine classes, and fighting wars. The modern equivalent to the muskets used by the minutemen. Keep 'em lubed with Slip 2000 EWL and they'll run reliably.
$400-$500 - Smith & Wesson M&P15 Sport II. Damn good for the price. Not combat-grade but good enough for most people.
$750-$850 - Colt LE6920. The cheapest combat-grade AR. Very popular. The LE6720 is a lighter alternative but harder to find.
$1000-$1500 - Any AR from BCM, Daniel Defense, or Sionics. To get the best gun for the lowest cost, personally I recommend buying a complete lower from Aero Precision or Palmetto State Armory and mating it to a complete upper from BCM, particularly the 16" MCMR ELW BFH with Mod 4B charging handle and either a BCM or ToolCraft bolt carrier group.
Ammo: For bulk storage and training, Wolf Gold .223 is awesome. Clean and reliable. Magtech 556B is similarly priced but more accurate at distances greater than 500 yards, so it's a better option if you don't mind the slight increase in cost. For home defense, Hornady TAP 55gr or 75gr is expensive but a top choice, followed by Speer Gold Dot 62/64gr which is more reasonably priced and also very effective.
You can use Gun Deals to compare prices on guns and accessories and Ammo Seek to do likewise with ammo. Check your state laws as some put restrictions on who/what can be bought.
When buying a firearm online, during checkout you select a local FFL dealer (federally license firearms dealer, aka a gun store) to ship to, and out of courtesy you should call or email them with your contact info and what you ordered. They then notify you when it arrives, and you go in and do the background check. There's usually an FFL transfer fee you'll have to pay, ranging $15-$75. Fair price is $35. So you pay for the gun online, and pay for the FFL fee + background check fee at the FFL dealer.
Note that for ARs, you can buy the upper half online and get it delivered straight to your door. It's only the lower, specifically the serialized lower receiver, that needs to be sent to an FFL and get the background check done.
Lights -- Every gun should have a white light on it. Surefire, Streamlight, and InForce in order of quality/reliability. You need to positively identify a threat before even thinking of pulling the trigger. Last thing you want is to kill a child or spouse by accident because you couldn't see them too well in dim lighting.
Holsters -- Guns like Glocks don't have manual safeties. That's good because under stress you may forget or fail to flip the safety off and die because you couldn't get off a shot in time. As such, the holster is the safety as it covers the trigger area. Holsters are needed for concealed and open carry, but for home defense you can get away without having one.
If you keep a loaded handgun bouncing around loose in a bag or purse, it better be in a holster or trigger cover like the RCS Vanguard 2.0. Look to Bravo Concealment, Raven Concealment, and Safariland for your holster needs. This is where it pays to have a popular gun like the M&P or Glock and a popular light like the Streamlight TLR or Surefire X300 series. Holsters for other combos are harder to find.
Slings -- For long guns like pistol caliber carbines and AR15s, slings are generally a good idea. Takes the load off your arms if patrolling, standing around all day during a carbine class, pulling sentry duty, hunting, and so on. The Vickers Sling and Proctor Sling are my favorites. For home defense, slings are a tangle hazard and take a few seconds to put around you, but they do keep a bad guy from yanking the gun away from you.
Handgun sights -- On a handgun, regular iron sights do the job. Think more in terms of quick combat sights than precision target shooting sights. Handguns are used at close ranges and speed is more important than fine precision. Laser sights can be helpful for the lesser trained since it's more point and click. Red dots on handguns increase accuracy but reduce speed and require considerable training to use effectively, so they're not a high priority here.
Red dot sights -- On rifles/carbines these are highly recommended. It's literally a red dot superimposed on what you see through the optic. Where the dot is, the bullet goes (notwithstanding holdovers and bullet drop of course). The problem with regular iron sights is that you can focus sharply on the front sight or on the target, but not both, so one or the other will be blurry and it takes longer to get everything lined up. With a red dot, it's point and click and everything is in focus. Unlike a laser, a red dot has battery life in years and is more reliably visible in all conditions. Options in order of budget: Primary Arms Advanced Red Dot with rotary knob, Aimpoint Pro, Aimpoint T2. Note that if you have uncorrected astigmatism in your eye, a red dot will look distorted and reduce your accuracy, so if that's the case for you then look into a 1x prism scope like the Primary Arms Cyclops.
Magnified optics -- If you need to shoot past 100 yards, then magnification helps considerably. It also helps if someone is shooting at you from behind cover, even at 50 yards, where only half their face and maybe a knee might be poking out. Magnification helps you identify whether it's a hostile or the neighbor kid cowering behind a bush.
AR15s are precise enough that you do need magnification to make full use of its potential. For fixed magnification optics, cheapest good option is the Primary Arms 3x with the ACSS reticle, and best high end choice is probably the Trijicon ACOG TA31 with green ACSS reticle. They also make scopes with variable magnification, also known as LPVOs (low power variable optics) that go from 1x to 4x, 6x, or 8x. Anything under 300 yards: Trijicon TR24G, otherwise the Primary Arms 1-6x ACSS does the job.
Ear protection -- Foam or rubber earplugs worn beneath an electronic earmuff like the 3M Peltor Sport or Peltor Comtac III.
Eye protection -- 3M/Peltor SecureFit 400 or better.
The four rules of firearms safety: 1) Treat every firearm as if it's loaded, even if you "know" it's not. 2) Never point the gun at anything you are not willing to destroy. 3) Keep your finger off the trigger until your sights are on target and you've made the decision to shoot. 4) Be sure of your target and what is beyond it.
If you have kids, roommates, bad neighborhood, etc. you'll need to lock up your gun to prevent accidental firearm deaths and theft.
Take classes, watch videos, dry fire, practice!
If you're prepping for serious SHTF defense against armed groups, then read Contact! by Max Velocity.