What do you think of these small-bore, high velocity PDWs?

[Nightcrawler]

They seem to be all the rage in TV in film now, at least the P90 is.

There are two out there, that I know of. One is the FN P90 submachine gun, and the other is the H&K PDW. The HK model is not yet in full scale production. FN has also produced the Five-Seven pistol, a companion sidearm for their submachine gun.

Both are an attempt to garner soft armor penetration out of pistol rounds, and both succeed by using small bore, high velocity bullets. Their penetration is impressive, but their other ballistics are...well, not so much.

The FN 5.7x28mm SS190 round features a 31 grain bullet that leaves the barrel at 2,346 feet per second, and produces roughly 378 foot-pounds of muzzle energy.

The H&K 4.6x30mm round utilizes a 24.7 grain bullet at roughly 2,378 feet per second, for about 310 foot-pounds of energy.

Both rounds will easily slide through soft armor, to their credit, and that is something that even .44 Magnum won't do. However, it IS something that nearly any rifle round would do.

Both rounds also have a very low recoil impulse for making fast follow-up shots. On the other hand, at least from my point of view they are both rather lacking in the energy department, and have very small bore diameters to boot. Making matters worse would be the use of subsonic ammunition in either piece, for suppressed work. You can only make a bullet that small so heavy. The 5.7mm Sb193 subsonic round fires a 55 grain bullet at 984 feet per second. I'd much rather have a 230 grain or 255 grain bullet (from .45ACP or .45 Colt) going at that speed. But then, neither .45 will defeat soft armor.

The question is, can 9mm, .40, 10mm, and .45 be loaded to defeat soft armor, flak jackets, and kevlar helmets?

Don't get me wrong. I think both are very cool, and am glad to see such innovation. But I'm wondering what the real-world unility of either piece is. I know they were INTENDED for rear-echelon troops, but in all honesty there's no reason that support troops can't carry rifles like they do now, especially lightweight and handy rifles and carbines like the M16 and M4.

I also don't know what kind of permanent wound profile either of these rounds makes, but I imagine it's not that impressive. Sure, you give the badguy two holes to bleed out of, but I'd rather give him two BIG holes.

So, without actually being able to test one, what do you think? Do either of these weapons have a place on the battlefield? What about for law enforcement? Should police be carrying P90s and Five-Seven pistols instead of MP5s/M4s and 9mm or .40 pistols?

Let's pretend that the country was as it SHOULD be and all three weapons were available on the market. Would you buy the P90? The Five-Seven pistol? The HK PDW? Would you CCW the Five-Seven pistol, or use it for home defense? What about either of the subguns?

Finally, one last question. The P90 magazines originally had a problem in that they were fragile, and dropping a partially loaded mag would cause the rounds to scatter in it, making for a pretty nasty jam. Have they fixed this?

 

[duck hunt]

No, these little bottle-necked smallbore rounds do not cause the massive tissue disruption that one might expect from a +P .45 JHP, but, as you say they were not intended to. They defeat body armor, have low recoil, less bulk than a rifle. I agree for rear area troops, the M-4 makes more sense, but for police and certain types of entry teams, the little HK would be handier.
With proper shot placement and perhaps a two-round burst option, the HK would smite kevlar-skinned hooligans just fine.

To get a 9mm slug to disregard body armor like these little rounds do, I think you would have to get them moving at 2,000fps, and that would be quite a chore.

 

[Tamara]

The question is, can ...10mm... be loaded to defeat soft armor, flak jackets, and kevlar helmets?

Only by necking it down to make .224 BOZ.

 

[Nightcrawler]

I don't know. I've heard of armor piercing pistol ammunition used in places like South Africa and Europe. Invovled making a very hard bullet with a pointy nose, sitting on top of a hot charge. FWIW, typical flak jackets as seen in most militaries aren't designed to stop bullets and are very poor at it. More modern armors are being seen more often, but those involve the use of steel or ceramic plates, which 4.6 adn 5.7mm rounds won't defeat anyway. In lots of places, armor isn't even commonly issued, especially in the third world, or amongst terrorist groups.

Still, no one's answered about the Five-Seven pistol. Given the option, would YOU pack one for self defense? Why or why not?

While they 5.7mm round doesn't have much energy left over after penetrating armor, it's better than not penetrating the armor at all.

...On the other hand, it's fairly anemic for use on NON-armored targets, and it's impractical for people to carry two submachine guns around, one for armored and one for unarmored targets.

One thing these weapons do have to their benefit is penetration. I DO like penetration. I wonder how well they penetrate hard cover, like dumpsters, cars, walls, etc.

 

[Tom C.]

New FN .22

Let's see. Less velocity than a .22 Hornet. Penetrates body armor. Makes a .223 look like a canon. Do I want one? What for? Are burglers expected to be wearing body armor? If not, I will stick with conventional rounds.

 

[Nightcrawler]

Here's FN Herstal USA's info on 5.7x28mm ammunition.

FNH USA, Inc.
5.7x28mm WEAPON SYSTEM

The 5.7x28mm weapon system is comprised of three components: the 5.7x28mm ammunition, the P90 Sub-machine gun, and the Five-seveN handguns. The 5.7x28mm SS190 ammunition has been designed to bridge the gap between the 9mm ammunition and the 5.56 x 45mm. The 9mm FMJ round will not penetrate modern body armor and the 5.56mm (.223 Rem.) rifle ammunition creates over-penetration concerns in a close combat situation or urban warfare. The SS190 has unique design, utilizing two metal inserts. The tip of the ogive has a steel penetrator followed by an aluminum core that is heavier than the forward tip. This causes the bullet to tumble in soft body tissue after 2 inches of penetration. This design virtually eliminates the risk of over penetration. This also creates a large wound cavity and quick incapacitation. The SS190 will perforate 48 layers of Kevlar up to 200 meters when fired from the P90 and achieve the same result up to 50 meters with the Five-seveN handgun. The 5.7 ammunition has only 60% of the recoil impulse of a 9mm. The muzzle velocity of the SS190 is 2,346fps when fired from the P90 and 2,133fps with the Five-seveN. Tracer, Sub Sonic, Training and Blank ammunition available. Ammunition is supplied in the U.S. by Olin.

More information can be found at the link at the top of this post.

 

[Tamara]

I'd be interested in a P90, if only for the novelty value. I like the ergos a lot, but the jury's still out on the cartridge. (I'm not a real "early adopter": it took ten years of circling and sniffing warily for me to buy a Glock, for pete's sake. )

 

[Nightcrawler]

Interestingly enough, you see more of these things on TV and in the movies now than you do in the real law enforcement community. I've seen a P90 once, in some footage of a hostage takedown in South America, and that's it.

Anybody know of any law enforcement or military units that use any of the three weapons?

 

[braindead0]

The question is, can 9mm, .40, 10mm, and .45 be loaded to defeat soft armor, flak jackets, and kevlar helmets

Sure, put one of these small diameter bullets into a sabot and load hot. Of course, then you'd have the same disadvantage re: tissue damage.

It sounds to me like they are thinking quantity of hits as opposed to quality.

 

[T.Stahl]

My opinion is that guns like the HK PDW (MP7) were developed to meet some abstract demands.
- it has to penetrate x layers of kevlar at x meters.
- it has to be as small a possible.
- rapid loss of velocity to reduce the risk for bystanders.

Scenario 1, you're a LEO:
- Will you engage targets beyond 100m with such a weapon?
- As a member of an entry-team, do you need an as-small-as-possible weapon, using as-light-as-possible ammo?
- Will you shoot to wound at long distances or shoot to stop at a few meters?

Scenario 2, you're a truck driver in a supply unit, member of a tank crew,... :
- Would you like to engage an assault-rifle armed enemy with your PDW at 200m? What do you think your chances are that you will eliminate such an enemy instead of just attracting his fire?
- When the enemy has closed to 50m, whouldn't you want a weapon that will likely stop him dead with one or two shots instead of half a mag?


I think the question should not have been, "what's the smallest weapon that will fulfill these abstract demands?", but "what's the most effective weapon with regards to the circumstances the possible user will be in?"

 

[El Tejon]

Speciality tool for the DDDs. Feckless waste of space for the Big Army. Carrier of "Iwannacoolgun" virus for rest of us.

 

[hksw]

Hmmm. The link provided for the HK appears to be that of an MP5/10 or -/40 PDW. Do you mean this for the 4.6mm MP7 :

 

[Justin]

It sounds to me like they are thinking quantity of hits as opposed to quality.

I think what Braindead says sounds pretty logical.

These weapons are all designed to have low recoil and high capacity. From that, I'm assuming that the idea is to allow the user to make as many hits on target in as short a time as possible. Sure, the two big holes out of Nightcrawler's .45 are going to do more damage against an unarmored BG than two out of a P90, but I think the idea behind the P90 or FiveseveN is to give the badguy 20+ holes from which to bleed out of.

 

[Tamara]

...and as any cylinder head engineer can tell you, more small ports flow better than one big one.

 

[seeker_two]

I had the opportunity to shoot a P-90 & a Five-Seven at a Class III shoot a few years ago (great way to spend a 4th of July). Very little recoil, & good penetration on an old car we were using as a target.

One of the TV shows that prominently features the P-90 is STARGATE SG-1. The later seasons have them taking them to every alien world--sometimes eschewing alien weapons to take them.

Personally, if I were going to operate on an alien world w/ no backup & possible hostiles around every corner, I'd take an FAL & as many mags of armor-piercing as I could....

(And a Redhawk .454 as my sidearm... )

 

[Nightcrawler]

True enough, but there comes a point (I think) when your need to shoot the badguys mulitple times can negate your capacity advantage.

It's a good thing the P90 has fifty round magazines, and the pistol has 20 rounders.

Me? I'd verymuch prefer a 13" FAL with a folding stock for CQB, but then, I'm a bit of an oddball. Loaded with 150 or 180 grain soft points, I wouldn't have to worry about either penetration or stopping power (though overpenetration might be a minor concern, but I'm not a cop).

Yeah, baby.

 

[seeker_two]

Yeah....

Bet that would make a few aliens run home to their mother---ships...

 

[sixgun_symphony]

This is a specialized class of weapons for fighting indoors against opponents wearing body armor.

Regular infantry may find these weapons useful for urban warfare. The Marines, Navy, and Coast Guard may find them useful for boarding ships.

SWAT teams will want to add these to their arsenals.

 

[Nightcrawler]

Actually, a guy I know in the Coasties told me they stopped issuing M16s to the Coast Guard on the Great Lakes. (Some politician complained it was too military or something). In any case, with some of the dinky little boats the coast guard boards, overpenetration is a serious concern, even moreso than in your house. I mean, if you shoot a hole in the floor of your kitchen, your house doesn't sink.

As for the aliens...buddy of mine is a HUGE Stargate fan. From what I've seen, a regular FAL rifle would do just fine on those kinds of missions. Most of them are in the great outdoors or are in temples that are spacious enough that a 43" battle rifle isn't going to be a disadvantage, especially considering the 6-foot long blaster-staffs the badguys use.

 

[jbutenhoff]

Why they are not used.

In case you have not noticed, these weapons are not used by either military or law enforcement for very good reason. First if the target is not armored then the rounds zip right through causing minimal damage, plus endanger those behind. Second they overpenetrate walls. Third if the target is armored they do defeat the armor but do little to stop the targer.

They are ineffective at best, dangerous to civilians due to overpenetration at worse. I do not know about you but I would rather shoot a BG one time rather than having to do multiple shots in a high stress environment. Give me a M4 any day! They do not overpenetrate with standard ammo (surprisingly) they will put down a BG in one shot and they are about half the price!

Jamie

 

[Schuey2002]

Tell me who's handing these weapons out and I'll stand in line?!

 

[Correia]

I wouldn't carry the FiveSeven even if I could. The trigger pull is horrible.

I'm not convinced that these new super fast little rounds are going to turn out to be very effective.

Now if they made something like the P90 in .223 we would be talking.

 

[Oleg Volk]

First if the target is not armored then the rounds zip right through causing minimal damage

That's not what I hear from the users. The bullet fish-hooks and ends up functioning like a mini-5.45 Russian. Not great BUT the whole point behind this is that the weapon helps to get a fast and accurate hits at ranges exceeding what's practical with a typical pistol.

From experience limited to airsoft P90, I'd say ergonomics are a huge win (it is streamlined, points well and deplays fast). Caliber is debatable but a P90 would be re-made in another caliber. 4.7FN is a decent caliber though: flat shooting out to the limit of its effective range, enough punch to do some damage. If I had access to a PDW (any controllable SMG of roughly P90 or Beretta S12 form factor), I would carry it instead of a large handgun.

 

[Mark D]

Correia...

Something like this???

 

[Nightcrawler]

They do not overpenetrate with standard ammo (surprisingly) they will put down a BG in one shot and they are about half the price!

Well, sometimes. 5.56mm won't overpenetrate if the ammunition fragments. While 55 grain ball will often fragment, I don't think it does so reliably enough to bet on it. It IS moving at 3000 feet per second, after all, overpenetration must be considered. SS109 ammo doesn't fragment at all. The reason for this is simple. The military doesn't use AR-15s for home defense, they're not worried about putting a bullet into nice Mrs. Wilson next door, or one of her twenty cats. They DO want a round that can hit a badguy hiding behind cover, something a reliably fragmenting bullet won't be very effective at. It's a tradeoff.

A 5.56mm round will usually put a man down. It's not exactly the most poweful round out there, though. Still, it's 1,200 foot pounds of muzzle energy, and that's enough to put the hurt on somebody.

In a combat setting, you don't care about overpenentration. You WANT overpenetration. You WANT to be able to hit the guy behind cover, and to give the sucker two holes to bleed out of, especially if you're not using expanding, fragmenting, soft-tipped, exploding, or otherwise extra-nasty ammo. Hence my preferance for the .308. But again, I'm an oddball, trying to use "obsolete" battle rifles in situations that any ultimately tactical SEEL will tell you can ONLY be survived with a tricked-out AR-15...