PDW's... FN PS90, M1 Carbine, AR pistol or something else?

[ugaarguy]

If it's not SBR, it's not a PDW. So, anyone talking PS90s or M1 Carbines really isn't talking PDWs, they're talking about something else.

Actually an M1 carbine is a PDW, and was never an SBR. Also, if we're talking modern PDWs like the P90 and MP7 if they aren't full auto they aren't truly PDWs either. Since none of them were made before the registry was closed in '86 they aren't legal for private ownership at all. So, SBR (even though legal with NFA paperwork in some states) vs. non SBR is a valid point, since we're really discussing PDW based firearms that are legal for private ownership.

Of course there are trade-offs with PDWs, their ballistic performance is inferior to full rifles (But then again so are SBR 5.56 carbines), but their ballistic performance is better than pistols of the same calibers.

If it's a pistol caliber it's not a PDW, it's an SMG or a private ownership legal PCC variant thereof. You should master the terminology yourself before you tell others that they're not using it correctly. Also, pistol calibers out of pistols, SMGs, and PCCs still have the problem of massive over-penetration compared to intermediate rifle rounds.

Why a PDW instead of an AR for that? I like my ear drums.

I'd love to see scientific test data that 5.7x28 or 4.6x30 are less loud than 5.56 NATO or similar rounds. Because I'm not buying it based on existing testing - http://www.freehearingtest.com/hia_gunfirenoise.shtml. A suppressor to reduce the sound or at least a linear comp to direct the pressure wave away from yourself is going to be far more effective in reducing ear damage / hearing loss than caliber choice.

 

[benEzra]

Funny, I just had a conversation with a pal today that touched (sort of) on my opinions here. He was saying something I've long believed -- that a trained person with a handgun will be faster on-target and just more effective with a handgun than any sort of shoulder-stocked arm -- out to 25 yards or so. His experience matched my own: When presented with the option of shooting through a scenario with targets presented between 3 and 25 (or more) yards, the fastest shooters were ALWAYS pistol shooters. (Based on his experiences as a 3-gun safety officer for several years.) The rifles, for all their vaunted ease of aiming and better accuracy and optics, just don't transition as fast and sight as quickly.

Sam, I wonder if that would change if you ran the same comparison in low light, where light-manipulation issues and the optic vs. irons thing would come into play more.

 

[goon]

If it's a pistol caliber it's not a PDW, it's an SMG or a private ownership legal PCC variant thereof. You should master the terminology yourself before you tell others that they're not using it correctly. Also, pistol calibers out of pistols, SMGs, and PCCs still have the problem of massive over-penetration compared to intermediate rifle rounds.

If the guys who make it call a pistol caliber firearm a PDW, who am I to argue? Just sayin'...

THE MP5K-PDW
The MP5K-PDW (Personal Defense Weapon) is essentially an MP5K standardized with a folding buttstock and threaded barrel. A compact submachine gun designed for vehicle operators, aircrew members, security details, and others who require a small, but powerful weapon; it is comparable in performance to full size MP5s. The size and weight of the MP5K-PDW make this weapon the ideal choice where a rifle or full-sized submachine gun is unmanageable and a handgun is a poor compromise.

http://www.hk-usa.com/military_products/mp5k_general.asp

 

[ClickClickD'oh]

One point is that some of us would have to clear our houses in an invasion scenario as children live in other parts of the house.

Get a better plan then. Clearing your own home is a pretty good plan for getting dead. Unless you happen to be ex-military... and live with about five or six other ex-military people.

Actually an M1 carbine is a PDW, and was never an SBR. Also, if we're talking modern PDWs like the P90 and MP7 if they aren't full auto they aren't truly PDWs either.

Contradiction detected... If the M1 Carbine is a PDW, But PDWs are by necessity full auto... one of these things isn't like the other.

If it's a pistol caliber it's not a PDW, it's an SMG or a private ownership legal PCC variant thereof. You should master the terminology yourself before you tell others that they're not using it

The P90 uses a pistol caliber round... I guess it's not a PDW then.

FN must be confused...

I'd love to see scientific test data that 5.7x28 or 4.6x30 are less loud than 5.56 NATO or similar rounds. Because I'm not buying it based on existing testing - http://www.freehearingtest.com/hia_gunfirenoise.shtml.

Your test data does not indicate barrel length for the pistol tests. Nor does it seem to include decibel levels for either the 5.7x28 or 4.6x30 out of any length barrel, pistol or PDW.... So, it's not really relevant at all.

Since I fire both the 5.7x28 and the 5.56 off of the same lower regularly, I can say that out of a 10 inch barrel the 5.56 is most certainly louder and generates a much more substantial pressure wave than the 5.7 does.

 

[Sam1911]

Sam, I wonder if that would change if you ran the same comparison in low light, where light-manipulation issues and the optic vs. irons thing would come into play more.

I don't know. While I have a lot of experience shooting in low- and no-light scenarios with a handgun, I don't have that experience with a long gun. Only one training situation I can remember let us do that, and the set of ranges I generally shoot on are not usually permissive of low-light long-gun work.

I see two possibilities, though. Weapon mounted lights might make the two about even. However, a non-mounted light obviously strongly favors the handgun.

 

[ugaarguy]

Contradiction detected... If the M1 Carbine is a PDW, But PDWs are by necessity full auto... one of these things isn't like the other.

It's not contradictory at all. I distinguished the M1 carbine from the MP7 and P90 with the phrase "modern PDWs". The distinction is that the modern theory of the PDW utilizes volume of fire (full auto) to compensate for the even lighter cartridges they use.

The P90 uses a pistol caliber round... I guess it's not a PDW then.

FN must be confused...

I strongly disagree, and branbwt explained it quite well:

5.7 was designed for the carbine, the pistol a later addition to the docket. 5.7 is a pistol round just like 30 Carbine (Redhawk) and 45-70 (BFR)

Your test data does not indicate barrel length for the pistol tests. Nor does it seem to include decibel levels for either the 5.7x28 or 4.6x30 out of any length barrel, pistol or PDW.... So, it's not really relevant at all.

It's completely relevant because every combination of firearm and cartridge tested exceeded 150 dB. That's 10 dB over the pain threshold, and far above the 85 dB pressure level where permanent hearing loss begins. So, when you say "Why a PDW instead of an AR for that? I like my ear drums." , you're incorrect, because discharging any firearm that doesn't have a supressor without wearing hearing protection is going to damage one's hearing. So, unless someone shows me scientific data that the 5.7x28 or 4.8x30 cartridge out of a pistol or carbine is significantly quieter / produces a significantly less powerful pressure wave than every other modern cartridge in existence I'm not going to accept that they're significantly safer for human hearing. Hence, I stand by my statement that hearing protection, or a sound suppressor are FAR more significant in protecting hearing than is choice of cartridge. I stand by my opinion that if ear pro or a suppressor isn't an option then a linear compensator to direct the pressure wave away from oneself is also going to be more significant than caliber choice. I'll also admit that indoors ear pro or a suppressor are the only things that are going to save one's hearing because the ceiling, floor, and wall are going to reflect much of the pressure back toward the shooter; regardless of muzzle attachment (or lack thereof).

 

[C-grunt]

Get a better plan then. Clearing your own home is a pretty good plan for getting dead. Unless you happen to be ex-military... and live with about five or six other ex-military people.

How exactly am I supposed to change my plan if rooms are separated? I'm not going to leave my 4 year old to fend for herself.

Also I do happen to be ex military and a current LEO in a major city. I clear structures on a regular basis.

 

[1SOW]

re total length vs bbl length: Bullpup design? Short total length with same bbl. length.
Designed to be more agile in tight quarters than the longer ARs and not much longer than the AR pistol. Some are carbine length with rifle bullet speeds.

re pistol vs 16.5" bbl AR inside 25yds: pistol wins in 3-gun often.
On the other hand, All 3-gun tells you is the "speed and hit factor of the shooter with the weapon", not the effectiveness of the hit.

 

[Sam1911]

re pistol vs 16.5" bbl AR inside 25yds: pistol wins in 3-gun often.
On the other hand, All 3-gun tells you is the "speed and hit factor of the shooter with the weapon", not the effectiveness of the hit.

Accepted, but there's no really valid reason to say that any of the "PDW" rounds are as effective -- and certainly not MORE effective -- than a quality handgun round.

So what then is the point? Yeah, I can't hit better and faster with the PDW, but at least the cartridges aren't as potent... ...?

(If you really were firing full-auto, with a zero-recoil weapon making 10-15 hits a second I'd maybe accept the trade off. Firing a semi-auto? No.)

 

[USSR]

Contradiction detected... If the M1 Carbine is a PDW, But PDWs are by necessity full auto... one of these things isn't like the other.

Sorry, but not buying that a PDW is by necessity full auto. PDW is kinda like Mil-Spec, Tactical, etc.; the term is used fast and loose and there is no one definition carved in stone.

Don

 

[Bartholomew Roberts]

Well, it appears one problem with this discussion is several different definitions of what a "PDW" is to begin with.

Having said that, if a PDW is a personal defense weapon for vehicle crewman, I can absolutely see valid uses for civilians. While it doesn't happen in the U.S. too often (yet), roadblock robberies are not uncommon in other parts of the world, particularly Africa and South America. If I were a driver or passenger there, I could see value in a shoulder fired weapon that was short enough to be carried on body in a vehicle and employed either from the vehicle or as you dismount. However 25" is about the maximum OAL for a weapon used in that role, which in the U.S. means you have an NFA weapon.

I suppose you could try the same concept with a folding stock carbine or a 26" bullpup; but in my limited experience, even a 25" OAL is pushing it and difficult to bring into action quickly.

 

[ClickClickD'oh]

...you're incorrect, because discharging any firearm that doesn't have a supressor without wearing hearing protection is going to damage one's hearing

Really? That's the assumption you are going to roll with? Because I implied that the 5.7 out of a PDW is more ear friendly than a 5.56 out of similar length barrel, you are going to go with the assumption that I was implying that it would cause zero hearing damage? Let's not be silly

Let's do a practical test on this theory that all firearms are putting out similar decibels and pressure waves. Go to an indoor range. Crank off a couple rounds of 5.7x28 out of a P90, or .22 WMR out of an RMR-30 since everyone seems to think they are the same. Now crank off a .300 Win Mag on the same indoor range. Tell me which one you double muff and plug for... and which one gets the whole range complaining at you.

Hence, I stand by my statement that hearing protection, or a sound suppressor are FAR more significant in protecting hearing than is choice of cartridge.

You are arguing a point that was never contested. No doubt, EarPro is king for hearing protection, but I don't know anybody that sleeps with Earpro on their nightstand. So yes, even though the 5.7x28 will still cause some amount of hearing damage, anyone addressing the question honestly will tell you there will be less boom rattle and roll than the 5.56, which means less ear bleeding and better situational control.

Of course, if you sleep with Earpro and a Can, then it's a moot point... but I'd guess than about .05% of people that keep a firearm for home defense fit into that category.

Also I do happen to be ex military and a current LEO in a major city. I clear structures on a regular basis.

Then you know exactly how dangerous it is, and how horribly ill advised it is. If you are ex-military and LEO and you are advising civies to clear their own homes instead of sheltering in a defensive posture...

'nough said.

As for a better plan, try re-arranging who sleeps where in the house so you don't have to cross the whole house to get to your 4 year old child.

 

[9mm+]

This is quite the Energizer Bunny thread...it just keeps going and going. I've enjoyed reading all of the varying opinions and have taken key bits away from each point of view. It does seem, however, that there are substantially different definitions of "PDW"; like most things, there appears to be enough room for incongruence in the point-counterpoint.

 

[tahunua001]

the M1 carbine is not a PDW and the PS90 is a NFA compliant semi auto, short carbine as well. the P90 is a PDW. as far as I know the AR pistol in it's fully autmatic form is considered a sub machine gun as is the draco AK pistol.

 

[pezo]

As far as room clearing goes. Hear a break in I will call the police but at same time get to kids with gun in hand. No way I'd let them fend for themselves either. Most of the time these things happen to people the perps take off. In the un likely event they stay to shoot it out ill do my best. Gods will shall prevail. On another note The m1 carbine was/is totally a PDW. That's what it was created for in the general sense of the word. It fits that description better than being a carbine or even a pistol caliber carbine. But it appears there is a new specific category of "military" small arm that is adopting the term PDW based on specific features rather than just the nature of use. Hence the confusion. Like assault rifle. A term I refuse to use even when referring to the military restricted variants because it has been puked out over and over again by the anti's. I'll use defense rifle or military automatic rifle. But I'm done with assault rifle!

 

[Sam1911]

as far as I know the AR pistol in it's fully autmatic form is considered a sub machine gun

Are there any AR pistols in fully automatic form? (I don't mean made by hobbyist machine gun collectors for kicks.) As it fires an intermediate rifle cartridge it can't be a submachine gun. Those fire pistol rounds.

as is the draco AK pistol.

Again, ARE there any full-auto dracos pistols? A few made by SOT2s for "demo" (read goofin' off) purposes, but none issued to anyone for real uses.

From a US legal standpoint, all full-autos are just "machine guns" anyway.

 

[Baldman]

I'm no expert but personally a PDW wouldn't make sense to me. I'd rather have my AR or my handgun.
Now for my wife who is disabled and if you allow a PDW to be semi-automatic it makes fairly good sense to for her use in a HD situation. She would have a hard time holding my AR on target for more than a round or two and would have the same issue with my handgun. A PDW could be very useful for her, smaller, lighter and likely better adapted for her situation. I could either go with a PDW for her or build a very light, maybe carbon lower, 9mm AR.
Either option is better than nothing and a lighter weapon may help her to enjoy shooting more.

 

[HoosierQ]

I think, within the defined objective/purpose of a PDW, an M1 Carbine does it most admirably. The .30 Carbine round is pretty good. There may have been better even at the time but I don't know how well they'd work in a magazine fed semi-automatic.

I'd be very happy to have one at my side. However, since the advent of the M4, (preceeded by the 5.56x45) it's rather a pointless concept as an arm has been devised that works equally well for front line use and PD.

 

[C-grunt]

So yes, even though the 5.7x28 will still cause some amount of hearing damage, anyone addressing the question honestly will tell you there will be less boom rattle and roll than the 5.56, which means less ear bleeding and better situational control.

Of course, if you sleep with Earpro and a Can, then it's a moot point... but I'd guess than about .05% of people that keep a firearm for home defense fit into that category.



Then you know exactly how dangerous it is, and how horribly ill advised it is. If you are ex-military and LEO and you are advising civies to clear their own homes instead of sheltering in a defensive posture...

'nough said.

As for a better plan, try re-arranging who sleeps where in the house so you don't have to cross the whole house to get to your 4 year old child.

A) Firing a 5.56 indoors probably isn't going to make your ears bleed and isn't as disorienting as some people want you to believe.

B) I never said I was telling people to clear their own house.

C) Unless my whole family is going to sleep in one room Im going to have to go get the children. When I do Ill have my Colt 6920 in hand and will "clear" the parts of my house on my way to the children. I also have a dog or two who are going to let me know where the intruder is at.

 

[mljdeckard]

I have an M-1 carbine, and I think it is the ideal HD carbine, but at today's prices, I doubt I would buy one for anything I could have an M-4 do instead.

 

[strambo]

Heh, I'll stay away from the "PDW" term...

I think the best expression of the concept for civilians with everything available today would be an AR 15 platform SBR chambered in .300 BLK, 8-9" barrel. NEA CSS stock for bonus points.



Completely avoids the downsides of the 5.7/4.6mm chamberings while delivering better terminal performance than either pistol rounds or 5.56 in a short barrel. Pretty easy to build and reasonable cost.

 

[mdauben]

I don't know anybody that sleeps with Earpro on their nightstand.

<stands up and waves hand> Over here!

I've got ear and eye protection right next to my night stand gun and flashlight. If the situation alows me time to done both, I will.

 

[CornCod]

There may be something to be said for pistol caliber carbines in calibers bigger thn 9mm, like .40S&W, 10mm and .45acp. These sorta have some similarlity to Jeff Cooper's "Thumper" concept.

 

[barnbwt]

That's a cool rig, Strambo, and probably about as small as an AR can be made. What kind of kick would 300 generate in something that small/light? I have no experience with that particular round, but a heavier-and-faster-than-a-pistol round would surely degrade the rate of accurate fire (whether the difference is noticeable is my question ). Interesting idea, though; a round designed for subsonic/suppressor performance would be very nice for HD even without the can, as the flash and overpressure will be minimized (though the heavier slug could potentially over-penetrate and all that noise)

The above statements about caliber and hearing damage miss the point; anything down to and including 22LR will permanently damage your ears. The question is which will cause disorientation sufficient to degrade your effectiveness and ability to make hits accurately, quickly. I submit that 223 is excessive in this regard, based solely upon my first experiences wearing double-earpro at open-air gun ranges next to people with braked rifles sporting full length barrels. Unprepared for the magnitude of the blast, I was momentarily stunned --the pressure wave travels through your face, or something-- and had ringing ears after foolishly opening my mouth to say something shortly thereafter as another shot was let off --went straight to my ears through my mouth. It probably wasn't so bad for the shooter directly behind the gun, but if mere reflection off a steel roof could rattle me that bad, I shudder to think about a hallway. I haven't played with a linear comp; do they really reduce the boom from a short barrel that much in an enclosed space? I know our nation's finest in uniform have and will "make due" with whatever they are issued to get the job done, but I also know a great many of them suffer terrible hearing loss as a result of their valiant service.

There may be something to be said for pistol caliber carbines in calibers bigger thn 9mm, like .40S&W, 10mm and .45acp. These sorta have some similarlity to Jeff Cooper's "Thumper" concept.

Precisely, he perceived a gap between pistols and rifles that could be filled by...something. I think marketing to this niche is impossible, though (as seen by many responses on this thread ). A 'large pistol' or 'light rifle' as the case may be, will be almost as expensive as the next step up, due to a similar operating system requiring similar manufacturing. Ammunition will be big enough to be expensive, but the gun will be small enough that the user will appraise it with an eye on plinking (cuz smaller is cheaper ). And since no NATO/Comm nation uses 475 Linebaugh or 10MM, there will be none of the requisite milsurp ammo needed to make a gun worth buying :banghead:

FWIW, the thumper was:
18" long with stock folder
4.5 pounds unloaded Ghostring sights
Clean trigger
Chambered for .44 AutoMag
Muzzle brake and locked/delayed breech bolt to mitigate recoil
20 rd box mag
Semiauto only

So pretty much an M1 carbine blown out to his beloved 44mag
The Ruger Model 44 or Deerslayer or Deerfield or whatever it is now is probably a pretty close match. Kinda funny how the concept sought to perform the same function in the same size as "The PDW" --but using a completely opposite chambering. I imagine advances in body armor and bullets unforeseen at the time are the primary reasons why the concept was never explored (though we're coming right back full circle with high-caliber subsonic, semi-auto ARs)

TCB

 

[C-grunt]

Heh, I'll stay away from the "PDW" term...

I think the best expression of the concept for civilians with everything available today would be an AR 15 platform SBR chambered in .300 BLK, 8-9" barrel. NEA CSS stock for bonus points.



Completely avoids the downsides of the 5.7/4.6mm chamberings while delivering better terminal performance than either pistol rounds or 5.56 in a short barrel. Pretty easy to build and reasonable cost.

What I've been saying for a long time now. I don't think the 300 BLK is a great military rifle round for a combat rifle but I think it's probably the best PDW round available. With a good 110-ish grain super sonic round you have armor penetration and have good terminal effects out to at least 200 yards.