On 5.7x28mm Ammo For The PS90 and FN Five-seveN

FN Herstal PS90 rifle chambered in 5.7x28mm.

The firearms-buying frenzy continues unabated. Spurred by the Chinese Flu and civil unrest in many major metropolises around the United States, gun owners old and new are buying up whatever inventory they can get their hands on. The stalwart 9mm pistols and 5.56mm AR-15s are picked up as soon as the dealer stocks them. Even favored “B Caliber“ weapons are looking a little sparse. Ironically, it’s the normally-rare firearms that seem to pop up in the inventory and stick around for a few days, such as FN PS90, FN Five-seveN, and Ruger 57, all chambered in the rather exotic 5.7x28mm caliber…

“OK”, you might be asking - “Is this yet another caliber?”

Yes, yes it is. There’s untold hundreds of ammunition calibers out there, and this is one of them. Designed to be a caliber both for pistols and personal defense weapons (a vaguely-defined class of guns that fit somewhere between a submachine gun and a rifle), the 5.7x28mm was a response to an audacious request by NATO - to replace the 9x19mm cartridge.

Wait, what? Yes - NATO sought to replace something that essentially “worked” for many decades in worldwide military service. To learn why, we’ll have to take a look back.

A History Of 5.7x28mm

For decades, the most popular pistol cartridge in government service around the world was, and still is, the 9x19mm Luger/NATO cartridge. Reliable, easy-to-shoot, and easy-to-acquire, 9mm in all it’s flavors worked wonderfully for many decades since it’s inception in the early 20th. However, governments and companies alike were developing more effective armoring technologies, which were rapidly diminishing the effectiveness of 9mm. This was in the late 1980s, so computer-designed hollow-points had yet to really make a splash on the market. Also, the Hague Suggestion err Convention prohibited the use of hollow-point ammunition in warfare. So, as the old saying goes, if someone invents a bulletproof vest, someone else will just invent a better bullet.

With that in mind, NATO put forth a request for a better bullet. The responses varied, with eventually FN’s 5.7x28mm round coming out on top, along with it’s companion weapons, the P90, and the Five-seveN (that’s how they trademarked it) pistol coming out in 1990.

After a few years in development hell, and of course the cessation of the Cold War, NATO finally got around to evaluating the FN offering for real in 2002. By then, Heckler & Koch had gotten off their collective rear ends and developed a competing cartridge, the HK 4.6x30mm - another little sizzler of a round that took the ethos of “fast and light”, and ran with it.

FN had the advantage, with two developed weapons, as well as it’s design being somewhat related to 5.56x45mm, allowing for the cartridge to be produced on existing lines with a few modifications. The cartridge had also readily beaten the NATO tests, easily penetrating Level IIIA body armor. Yes, many rifle cartridges developed since the Civil War could penetrate IIIA, but 5.7x28mm was the first to do so “in it’s class” of size. Remember, the requirement was to be fired out of a handgun and a PDW-style weapon.

However, the Germans had major political oomph in NATO, and rejected 5.7x28mm for purely political reasons, bringing the standardization process to a halt. Along the same lines, more effective 9mm and 5.56mm cartridges had been developed, allowing for existing inventories of firearms to be able to meet the NATO requirement. Why buy a whole slew of new guns when all you have to do is load up your current ones with fancier variants of your usual ammo?

Despite this, and the lack of adoption by regular police and military forces, the 5.7x28mm, and usually it’s companion PDW, the P90, found acceptance with specialist units around the world, such as commando units in Belgium (where it replaced the UZI), Chilean Special Forces (even the ones that fly helicopters), Luxembourg’s police force (only the best to keep those holding companies safe!), and our very own United States Secret Service, where the firearm is utilized by both the Uniformed Division and the “Detail” itself in keeping the President and First Family nice and secure.

In other words, when it’s on someone else’s dime, it’s easy to splurge on this rather amazing little round.

FN Herstal PS90 rifle chambered in 5.7x28mm with SS195 LF ammo.

Pros And Cons Of 5.7x28mm

Like any cartridge, the design represents a specific answer to a specific question, so 5.7x28mm has some marked advantages and disadvantages. It’s not for everyone - but one should be informed to make a decision on whether to “bite the bullet”. Sorry, I had to.

Advantages to 5.7x28mm

  • Weight. The cartrige itself is very light, clocking in at two-thirds the weight of 9mm.

  • Velocity. The lighter projectile hustles along at nearly and sometimes more than twice the speed of the 9mm. Again, the school of “light and fast”

  • Capacity in a given weapon. With a standard duty pistol in 9mm, such as a GLOCK 17, you top out at 17+1 rounds in a standard magazine. In a Five-seveN, you have 20+1 rounds on tap. Those extra rounds can make a difference in a life-threatening situation. In the P90/PS90, you have 50+1 ready to go out of a standard magazine!

  • Negligible recoil. Guns chambered in this round typically shoot very flat and are highly controllable, even in full-auto. A more satisfactory learning curve.

  • With the proper projectile, the terminal ballistics are more akin to an intermediate rifle cartridge than a pistol round. Terminal ballistics is an ammo-nerd term which basically outlines how a bullet behaves when it strikes a target, be it ballistics gel or a threat.

  • Cool factor. Thanks to video games and movies, the PS90/P90 and 5.7x28mm round have a mystique about it. I just watched “Bad Boys For Life” and the P90 (depicted as the “P90 Herstal”) was portrayed as this super-exotic and ultra-rare weapon. Despite it not being so in real life. You can get the gun and ammo if you look. Don’t tell Will Smith that. He might get into an entanglement over it.

Disadvantages to 5.7x28mm

  • Cost. Even the cheap stuff is over $0.70 per round. The current joke is that if one carries a Five-seveN as their defensive weapon and has to use it, it’s probably cheaper to just give the assailant your wallet rather than shoot him.

  • Longevity. Right now, only FN, Fiocchi, and Federal make 5.7x28mm ammo. Compared to hundreds of shops, big and small, that make 9mm. FN could throw in the towel one day, stop making the guns and ammo, and the rest will follow suit. You could be stuck with a gun you can’t feed.

  • The really good ammo is ostensibly restricted nationwide. Known as SS190, it’s classed by the ATF to fit their definition of armor-piercing, and thus it’s technically not for sale to individuals in the US. It’s a legal grey area (in other words, you do so at your own risk), but one can purchase the projectiles themselves via many common channels. Small batches of complete ammo have been seen for sale for collectors and ammo nerds. Again, I’m not a lawyer and the “AP” classification is a huge talking point.

  • Availability. Even in good times, it’s hard to find. Now, during a panic, forget about it. Everyone I know with a PS90/P90, Five-seveN or Ruger 57 grabs all they can find in one fell swoop. One enterprising fellow I know of depleted a store’s inventory of 5.7x28mm recently. They had 50-60 boxes of it.

Cheap 9mm Ammo at Lucky Gunner

Firearms in 5.7x28mm

Love it or hate it, 5.7x28mm is a bespoke round. As of this writing, there’s only 4 somewhat commonly-produced guns for this caliber. Two of which came out over 20 years ago, and two others that came out within the last year.

FN PS90/P90 PDW

The definitive 5.7x28mm weapon, the FN P90/PS90 is what some describe as the ultimate “space gun”, with it’s insanely-ergonomic shape and compact arrangement. Fully-ambidextrous, the P90/PS90 can be used by righties and lefties with no modifications. In full-auto, the P90 is like a comfortable little buzzsaw. Unfortunately the P90 is on the restricted list here in the US, and is only available to government users, manufacturers, and dealers. If you see one in citizen hands, it’s probably an item in the possession of duly-licensed firearms dealer or manufacturer.

However, for the Regular Folk, the PS90 is available. Semi-auto only, with a 16-inch barrel for NFA compliance, it’s still a fun gun to shoot and is surprisingly compact, even with that dorky barrel. Unfortunately due to it’s highly-unorthodox design, the only way to legally possess this firearm with it’s proper short barrel is to make it into a short-barreled rifle, which requires the $200 tax, and filing the Form 1 registration paper with the ATF. More on that in another article.

Regardless, it’s a fun gun to have and shoot. Even the 16-inch barrel configuration has a specific use case for medium-range target shooting. Plus it’s kind of nice having something that compact with 50+1 rounds on tap.

FN Five-seveN Pistol

The companion to the P90/PS90 is the FN Five-seveN pistol. Designed around the same time, the idea was to equip users with both the P90, and the Five-seveN as a secondary weapon. The current version, the “Mk2”, sports more ergonomic additions as well as some engineering refinements. The pistol itself is a pleasure to shoot, with it’s lower recoil and higher velocity delivering more accurate shots for the user. Also one can’t argue with 20+1 rounds on tap. Since this is a pistol, outside of restricted jurisdictions, you can pretty much buy the same model that’s issued to government users. If you can find one.

Ruger 57 Pistol

Surprisingly, after 20+ years of seeming neglect, the 5.7x28mm cartridge showed some signs of life again in late 2019 and early 2020 with the debut of the Ruger 57. Ruger has been known to play around with unorthodox designs in the past, but them releasing a pistol for such a niche caliber took everyone by surprise. Plus, the price point of being well under $1000 can’t be beat. Typically, stepping into the world of 5.7x28mm required investing in the FN offerings, both of which clock in above $1000 easily. I have yet to run this pistol, but reports suggest it’s a winner, if you can find one and feed it.

CMMG Banshee 300 MK57 Pistol/SBR

CMMG isn’t one to stick to the norm. They have an insane variety of firearms. Some stick around, some don’t. But it’s good to see them try. And they too, as of 2020, have stuck their toe into the 5.7x28mm world with the Banshee 300 MK57 pistol/SBR. Available either in an arm-brace configuration or short-barreled rifle, you can jump into the caliber with a familiar AR-style weapon. I haven’t run this one either, but reviews suggest it’s a winner. It’s a bit pricey at over $1400 usually, but CMMG also offers a 5.7x28mm upper which will work with any standard AR lower. Cost is usually below $800, and you can use your existing AR accessories for the most part. Might be worth a look.

Should You Get A Firearm In 5.7x28mm?

Of course, the million dollar question is whether one should get a weapon in this uncommon caliber?

If it’s your first outing into the world of firearms? Definitely not. Aside from the cost of the gun, getting trained up on it will cost you a fortune. Assume a few hundred rounds or more just to get comfortable. Even if you go the cheap route with a Ruger 57 or one of the CMMG options, you’re still blowing through an insane amount of money for your first gun. Stick with a well-regarded 9mm pistol or AR-15, and just run cheap range ammo to get competent.

If you’ve got a few guns in the vault, and some extra cash or Trump Bucks burning a hole in your pocket and no real urgent financial committments? Then yes, get a gun in 5.7x28mm. My prime choice would be the PS90 - if you’re going to dive in, go all the way and buy the gun the caliber was made for.

Though the CMMG offerings look nice and present a viable option for the cost-conscious collector.

FN Herstal PS90 rifle chambered in 5.7x28mm.

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