Mossberg 500

Depends on your size, health (are you an old lady with no grip strength?) and purpose.

Go simple. 3 main paths: pistol, rifle, shotgun.

Assuming you want a self-defense weapon and have 0 training or practical experience (because you're asking on Voat for advice, you stupid), I would recommend either a pump shotgun or a rifle. Pistols are too easy to accidentally shoot yourself, and we've already established you're a stupid.

12 guage shotgun ammo is everywhere and good options exist for self defense. You also don't need "as much" training to hit something if you get defensive shells with some spread. Lots of pump options for less than 400. Stay away from semi automatic for that price.

If you can afford it, a rifle is a good option. Assuming you figure out how to run it, rifles are more accurate in use (longer sight radius etc etc) and you'll be less likely to accidentally point it at something you don't want to shoot. Also, kids are less likely to be able to pick it up and shoot themselves if your dumb ass ever procreates.

My advice whatever you do is not to go to pawn shops. Aside from a tendency toward horribly beat up and misrepresented firearms that fact is I have never seen a deal at a pawn shop. They make their money on interest and have very little incentive for the competitive selling of product. I've used hipoints for $250, I've seen dewalt impact drivers for $100, I've seen ten year old laptops for $300. Those are extreme cases, but the take away is that I have been to hundreds over the past 15 years and not once did I find a bargain. Even more so if you are too inexperienced to judge the value or condition of the product. You have numerous options. A big box store, anything from academy to walmart, will often have new guns at a similar price point. A local gun store will usually have a rack of used guns. In terms of value for money your best bet is to find a sale online and have it shipped to a local dealer. Gunbroker, linked in many comments, will walk you through the process but rarely has the best prices. Just a matter of whether the effort is worth it to you. I wouldn't recommend a gun show either as the prices are jacked up but even there you have better odds than a pawn shop.

Shotgun: Tons of options here under $400. Here is what I got in 10 seconds of searching $180 https://www.academy.com/shop/pdp/rock-island-armory-meriva-12-gauge-pump-action-shotgun?sku=12-gauge $219 https://www.academy.com/shop/pdp/mossberg%C2%AE-maverick%C2%AE-88-security-12-gauge-pump-action-shotgun?sku=right-12-gauge-18-5

Revolver: $263 https://www.guns.com/firearms/handguns/revolver/armscor-200-38-special-revolver-6-rounds-4-barrel-3-lbs-new?p=205799& $330 https://www.sportsmansoutdoorsuperstore.com/products2.cfm/ID/13044

Expect a small fee of around $20-40 for the ffl if you go that route. Also good for you for having your own preferences rather than starting off with a striker fired 9mm pistol or 9mm carbine like everyone else, because it is cheap to learn on without the bad habits of learning on a .22

Ruger GP100

Ruger SR9

Skip the gun and get cocaine instead

Get a Ruger GP100 in .357 with a 4" barrel for your first revolver. Mossberg 500 or Maverick 88 for first pump shotgun.

Find a cheap, local FFL and checkout GunBroker.com. It’s like an eBay for guns and ammo, but most of the ammo is overpriced.

They have plenty of new and used guns, but I highly recommend buying new if going for a pistol (unless you opt for the revolver). And don’t jump at the first thing you see.

To get and idea of what feels most natural in your hand, go to a local range that rents guns, gun shows, or anywhere local that sells guns and actually hold what you think you want.

It took me about 2 months, but I managed to grab a brand new Springfield XD9 for $380 shipped and transferred (with a promo for 4 free mags), and a used Ruger Security Six, or .357mag, for $400 shipped and transferred that was literally like new after a routine cleaning.

Helped a few friends find what they were looking for on there too.

Best of luck.

Get something that fits your hand well and has decent capacity. Do not buy a snub nose revolver ( 1”-7/8 to 2” - 1/2) .. If you buy a revolver, get a 4 inch barreled gun. Easier to shoot , far more accurate, and you could still carry it. No smaller than three inch.Whatever you do , don’t buy something to small for your first pistol. You could pick up a new Canik TP 9 in that price range although I don’t trust my life to Canik. Save another 100 bucks and buy a new Glock 19 or a Sig 320 , or a Beretta Apex , Smith and Wesson M&P ,there are a ton of 9mm handguns in the 3-1/2 inch to 4 inch range new for 500 bucks.

My first gun was a glock 23 due to ammo type, servicing, reliability reputation. It's small enough to conceal and light enough to not be a problem if I have to carry around. I didn't want the 9mm as it's weaker and will need to land more shots to take someone down so I went up to a stronger cartridge.

I suggest start small that is portable. A resolver is great for SHTF as they likely won't fail and usually a revolver can fire two types of ammo. I looked at a revolver as my first gun but I decided to go against that mainly because it's bulky and heavy so I got the glock. I'm happy with it. Shotguns are heavy and big, so it's not really portable.

Really depends what your goal is with this first purchase. Self-defense in the open? Hunting? Home defense? Answering that will tell you what you should get first.

First pistol or first gun in general? If it's your first gun in general get a 10/22 or a simple 12ga pump shotgun because those are good for everyday use and will be extremely useful in a shtf situation. They are also FUN TO SHOOT.

As far as revolvers for that price, a used Ruger would be my choice. I like my revolvers to be in .357 because .357 can handle .38 as well. It's nice to have the option. $400 may be stretching it for a revolver, however.