What's old remains old: the old ".45 versus 9mm" again rears its ugly head.

A friend raised an interesting point as to defensive handgun calibers. He noted that an argument against the .45 ACP is that it's "no longer effective due to advances in bullet technology in 9mm (and like) calibers." He wondered if that same technology upgrade didn't produce "better" .45 ammo. I have friends in the bullet business and in the ammunition business. I imagine when they realize that I'm hitting the keyboard in a discussion of defense handgun ammunition, the stores of intoxicants dwindle because I don't believe in 'handgun stopping power' – and I say so. It's not like religion. Faith involves believing in something you can't see, touch, smell, measure, test . . . in terms of people getting shot there is quite a bit of scattered information accumulated over a century.

Keeping empties in the air with a 9mm is a little easier than with a .45 -- especially as we age. That's not necessarily the best metric for fight-stopping potential.

But, let's go back to the technologically challenged .45 ACP. You can measure and collect data about the new-issue .45 Auto. Various bonded HPs, all-copper rounds and improved bullet designs make for some impressive performance in the artificial environment of the FBI tests – just like in smaller calibers. There are things they seek, among them penetration, and the new ammo is built to pass a test. How the test relates to the world varies: for many of us, no longer on the job, much of the test lacks relevance. For many police shootings, the test doesn't really say anything – but it is a test and it gives one a basis for comparison. One argument against the .45 is "less barrier penetration" including vehicle engagements. I've not seen compelling data to indicate that non-law enforcement has a compelling need for 'barrier penetration.' As to cars, those who shoot lots of them tell us that handgun calibers really don't "kill cars:" there are too many intervening variables (braces, supports, steering wheel cores, etc.). There is a difference on auto glass which, again, is largely irrelevant for most of us. Another thing is "less recoil, higher capacity" for the 9x19. Sure. That's a thing for a good many (see the FBI), but the capacity argument is not a big deal overall according to the few who examine shooting reports in some detail. Does this mean a two-shot 'derringer' type pistol is a good idea? You might ask why I nearly always carry a compact-service auto with a spare magazine – and it's a fair question. It's unlikely I'll need a gun at all: if I knew I was going to need any gun, I'd avoid the situation completely. The battle never fought counts as a victory.

A shotgun or rifle-caliber carbine is a better choice if fighting is actually necessary.

It's said that bigger handgun projectiles have a bigger impact and "transfer more energy." – No, they don't. Look at the size and speed of the projectiles: 147 grains weight versus 230 grains weight: that's nearly no difference, at 83 grains (.19 ounce). Compare both to a one-ounce (437.5 grains) lead Foster slug at around 1400 fps – well, there isn't a comparison. The difference in diameter is likewise irrelevant: 0.097" is nothing about which to write home. Remember, if it "knocks" the attacker down it has to knock you down too. Staying away from crossed platforms, by comparing Glock 21 to Glock 17, S&W M&P45 to M&P9, Ruger American .45 to Ruger American 9mm is helpful. If you throw the whole 1911 versus "fill-in-the-blank" thing in there, it's a whole different kettle of fish. Likewise, measuring the difference in split times is of little help. The difference between .15 and .30 is one-half the blink of a human eye. And no fight stops on a fraction of a second – it takes more time for the human attacker to close up shop. Is the .45 Auto a good cartridge? Sure. It's not for everyone, no more than the 9mm is – and we should be glad we can make the choice (in Free states). It's one of the most accurate handgun rounds in existence due to its extensive development as a match round as much as anything. It's as good as anything else for defense use, but my standards are pretty basic and have been often repeated here.

The load selected should fire, function the gun, penetrate enough and hit to the sights -- the last being critical as bullet placement is king.

Suffice to say, the round has to fire every single time (the best single reason for premium defensive ammo), it has to function the gun, it has to go deeply enough in the attacker to wreck important stuff and it needs to hit to the sights. Expansion, barrier penetration and other stuff is okay I guess but it's hardly critical. If there's just got to be a fight – and I really don't recommend it – I'd prefer a slug-loaded 12 gauge or a centerfire rifle-caliber carbine and some people with good attitudes who are likewise equipped. I greatly respect many of those who stake out one position or another as to handgun ammo, but it's just handgun ammo: it sucks in a fight. The pistol is handier than a rifle/shotgun and there's where we hit the wall. There's no significant difference in results downrange regardless of the service handgun calibers. And there's no need to give up if you have to use a 9mm for defense – or a .380 or a .22. If you ask why I carry 9mm, it's because it's cheaper, it's plentiful, and it'll do if you will. If carry of the .45 (or .40 or .357 SIG or .38 Special) warms your heart, I won't disparage you anymore than I would if you chose the 9mm. -- Rich Grassi