Just How Powerful IS 5.7x28mm?

Photo by: Bobbfwed at the English language Wikipedia

Just How Powerful IS 5.7x28mm?

A lot of people are interested in 5.7x28mm for home protection and/or for concealed carry. The argument goes that it goes through body armor (which, in fairness, it does; select loadings are known for penetrating up to Level IIIa) and that you get greater capacity, which means you’re MOAR ARMD!!! or something to that effect.

Just how true is the hype?

None of this is to say it’s a bad round, or that the guns it’s chambered in are bad guns. It isn’t. They’re not. This is to explore hype vs. reality.

5.7x28mm Ballistics

Be aware that not all published 5.7x28mm ballistics are necessarily equal. In fact, you need to take ANY advertised figures with a big ‘ole grain of salt.

Here’s why:

Ammunition manufacturers don’t always advertise what their test weapon was. As it happens, 5.7mm is also made for use in the FNH P90, which has either a 10.6-inch barrel or a 16.4-inch barrel. The 4.82-inch barrel of the FN FiveseveN and the 4.94-inch barrel of the Ruger-57 are going to produce less velocity and less energy than the P90.

From the P90, a 5.7mm projectile will achieve velocities in excess of 2,000 fps and muzzle energy in excess of 340 ft-lbs, and top out close to 3,000 fps and 400 ft-lbs. From a FiveseveN pistol or a Ruger 57, velocity in a 40-gr load drops to closer to a velocity of 1600 fps and muzzle energy closer to 220 ft-lbs.

Bear in mind that’s more like ballpark than gospel; there are a few different loads on the market, so you might find a bump in either figure. Regardless, the gist is this: faster than, but less powerful (in terms of ft-lbs of force) than 9mm.

But also, and this should be mentioned, with half the recoil. The 5.7x28mm also takes far longer to drop, not falling below point of aim until close to 150 meters.

Granted, you aren’t buying it for power alone, it’s for increased magazine capacity and penetrative ability, if practical purposes are why you bought one or are considering one.

Terminal Performance

The 5.7x28mm isn’t a magic bullet.

Ammunition testing by Dr. Martin Fackler that appeared in the Spring 2000 (Vol.4, No.3) of Wound Ballistics Review journal of the International Wound Ballistics Association (a professional society for people who study wound ballistics) found that even when fired from a P90 (the FiveseveN was not in production yet) a 31-gr loading – with an average velocity of 2329 fps – was capable of penetrating soft body armor, but average penetration didn’t exceed 10.6 inches even in bare gelatin, less than 9mm. Permanent wound cavities were roughly one-third the size of 9mm.

You can read it yourself here. It’s on page 21.

Among the YouTubers, arguably THE standard for ammunition testing is Paul Harrell, who subjects ammunition to the test of what he calls “The Meat Target,” which consists of pork chops (for pectoral muscles) over pork ribs (simulating a rib cage) which surround either a watermelon (if in season) or a bag of oranges to simulate lung tissue and organs, and backed up by a “high-tech fleece bullet stop” which is literally just a bunch of fleece blankets.

Watch for yourself. Skip to about 6:50 in to see the meat target.

The point here is that outside of certain attributes – a definite ability to penetrate body armor, flatter trajectory and greater magazine capacity – it’s not some sort of ballistic wunderkind. It performs pretty well for the size of the projectile, but it’s just not the great leap forward, some say.

But what about in the real world? After all, testing isn’t everything; what proves efficacy in the field is efficacy in the field.

5.7x28mm In Actual Use

Is there any information about 5.7x28mm in actual use?

Not much, but there’s some.

It’s in use with plenty of military and police units, albeit with the P90. Apparently, it works well enough for them to keep buying it.

It isn’t pleasant to contemplate, but the Ft. Hood shooter in 2009 used an FNH FiveseveN in the commission of his crimes. Thirty-two people were wounded, and 13 were killed. Lethality…is therefore established, including with center-of-mass hits. It’s alleged – if someone finds the autopsy reports or something else official that confirms it, let us know in the comments – that 5.7mm rounds tumble in tissue, leading to greater blood loss.

I haven’t found anything official about the round’s use in police service or used in defensive shootings. Some people on a number of message boards and forums ’round the interwebs have intimated or repeated second- or third-hand knowledge of agency use of P90s, and the results are said to be a mixed bag. Some found them effective, some not at all.

In short, it appears that the 5.7x28mm round IS effective in the real world, despite the deficiencies compared to traditional cartridges used for personal defense. 5.7mm has a flatter trajectory, meaning you can hit targets more easily at longer range. It is definitely effective against soft body armor, though it doesn’t overpenetrate when used on fleshy targets. You can definitely carry a lot more rounds. That said, 9mm is the default for a bevy of good reasons, and that isn’t likely to change.

But you pay for the privilege. The guns cost more. They aren’t the easiest pistols to conceal. The ammunition costs more and isn’t nearly as widely available. And do those costs totally justify the benefits? Well, that’s up to you.

Look, there’s no perfect cartridge. The question is what deficiencies you are comfortable living with.