One of the most common misconceptions I've heard both on the range and in classes is: "isn't hollow point ammunition illegal?". The answer is no. Hollow Point ammunition is not illegal. However, lets talk about what exactly is hollow point ammunition and what makes it different from "every day range ammo"?
Hollow Point ammunition means that the bullet has a hollowed-out space or divot in the nose of the bullet which causes it to exponentially expand upon impact. The most significant benefits of this expansion (as pertaining to self defense) are: 1. Less Penetration, and 2. More internal damage. The reason you might want decreased penetration is because if you're shooting a "bad guy" in a self defense situation, either in public or in your home, the chance that the bullet could go through the target (a body or maybe even a wall) and cause collateral damage is notably lessened with hollow point bullets. You might have heard the term "stopping power" when referencing ammunition at a range or pro-shop, this typically means that the round that has the most velocity or size or expansion supposedly is the best for stopping a threat the quickest. Not always. To stop a threat the fastest means you need to cause the most internal damage. A carefully placed round-nosed FMJ can do a lot more damage than a JHP that hits, lets say, a less vital area of the body. The benefit of a JHP is that upon expansion internally it is tearing at tissue, possibly organs, and hopefully bones as it travels through (and not always stops in) the body.
There was a recent case here locally where an unwanted intruder forced his way into a home and the homeowner, trying to protect his family, shot him twice. The injured intruder was arrested and the homeowner is not currently facing any charges. Whether the family-man intended to simply injure the intruder or not is unknown, but lets use this case as an example. A lot of self-defense cases here in CA end in a lawsuit, whether civil or criminal it is almost expected. It is more common than you might think, and scarily so, that shooting a bad guy once or even multiple times doesn't always mean that the threat stops. It doesn't always mean they fall down and stop coming at you like they do in the movies. If this was true then this particular homeowner might not have needed to fire a second round. The mindset needed when choosing self defense is survival. When the situation is "it's them or me" or "I need to protect my children" then the thought that it might result in some court case is not the first thing I would think about, personally. My first thought would be to keep myself and my family alive and well. So when choosing ammunition to keep in my home-defense firearm I would logically choose the ammo that, together with training, would be the most likely to guarantee that I can stop a threat if I ever have to.
A good rule I like to set is this: Practice with FMJ at the range and keep JHP at home for self-defense or carry. There are many different brands and hybrids of hollow points so when you purchase JHP make sure to cycle a few through your semi-auto to make sure that your firearm works well with that specific kind. If it does then buy another box or two and keep them on hand.
I know this is a topic that can be discussed for hours; the pros and cons, the rights and wrongs, the what-if's, the studies and ballistic tests - but I hope this answers the most common questions about hollow point ammunition.