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Super-Dave
May 22, 2008, 11:47 AM
I am curious about when a shotgun would be a better choice than a full auto submachine gun. I see swat teams all the time with some members with shotguns and others with submachine guns. I know the shotgun can be used for breaching but this is a more recent phenomenon.

Supposing a swat teams enters a building looking to clean out a bunch of armed dangerous thugs. If they knew in advance that the thugs did not have body armor. When would it be better for them to use shotguns or full auto submachineguns?

I know most swat teams have abandoned the 9mm, .40 submachine guns for the Ar-15 carbine due to over penetration issues. But even for them under what scenarios are you better off with the shotgun?
__________________

ISC
May 22, 2008, 11:55 AM
12 ga slugs work well to bust locks and hinges. SMGs don't

tackdriver
May 22, 2008, 12:14 PM
I know most swat teams have abandoned the 9mm, .40 submachine guns for the Ar-15 carbine due to over penetration issues

Does this make sense?

carguychris
May 22, 2008, 12:27 PM
Does this make sense?
Yes. 5.56 FMJ bullets will disintegrate upon impact with just about anything, lowering the chances of collateral damage. Excerpt from a recent Rifle Shooter article:

"It is a surprise to many people that the round that works best for going through walls is the 9mm. With relatively higher velocities, the .223 bullets generally break up upon impact, even when hitting a thin sheet of drywall. The resulting small fragments quickly lose their energy. Bullet selection plays a part in this, but even the toughest FMJ bullet tends to virtually disintegrate when it hits wood or drywall at 3,200 fps....

With most of the .223 ammo screaming along at more than 3,000 fps, the bullets are prone to flying apart when they impact virtually any medium. Even FMJ ammo breaks up dramatically when it hits sheetrock at these velocities."

Full text here:

http://www.rifleshootermag.com/featured_rifles/ar_patrol/

Bill DeShivs
May 22, 2008, 12:30 PM
I have seen fmj .223 bore a clean hole in 1/4" steel plate, and eat up a brick wall behind it. I don't think 9mm will do that!

Erik
May 22, 2008, 01:23 PM
"Does this make sense?"

Another yes, given most ammuniton, certainly most issued to patrol officers and tactical teams. Are there options affording greatere degrees of penetration? Sure. But, I've had the oportunity to observe a MP5 magazine dump into the side of a car followed by the same from an M4 into another. (Same make and model; same target area.) It was clear that more of the 9mm rounds made it thorugh; many more, in fact.

"But even for them under what scenarios are you better off with the shotgun?"

Where close range, rapid, clsoe enough accuracy is called for and third parties aren't in close enough proximity to the subject beingshot at to be a concern.

Very similar criteria, by the way, for when you might flip the lever to burst on an M4.

JollyRoger
May 22, 2008, 01:37 PM
The 5.56 does not stabilize for a distance out of the barrel. During this unstabilized flight, the bullet will apparently upset and not overpenetrate bodies and/or other objects struck. After the bullet stabilizes, however, it will drill a nice hole in all sorts of things. I have no personal experience with this, but I do recall speaking with a member of a local SWAT team who shot a pit bull at close range with a M4 and the bullet stayed in the dog.

Back to the OP, advantages of a shotgun over a subgun for entries can depend on the ammo. With buckshot, you can put 9-12 pellets (and wound channels) on target at one time out to moderate ranges, which is hard to do with even a good subgun like an HK. All subguns climb, so unless you are really close, you are limited to bursts of 3-4 shots to keep on target, as opposed to the shotgun which delivers all pellets with one recoil impulse. With slug loads, you can penetrate most soft body armor at moderate ranges, which a subgun will not do (I know it gets bantered around that slugs won't go through the vest and will injure through blunt trauma, but I have seen a vest, IIA or III, penetrated through both sides in a test by a local PD).

Subguns, however can go from a multi-round weapon to a precision weapon out to moderate distances simply by going to semi-auto, and the ones that fire from a closed bolt are usually very accurate, with obvious SWAT applications. Tough to trust a close head shot to a shotgun.

Boris Bush
May 22, 2008, 04:33 PM
JollyRoger

The 5.56 does not stabilize for a distance out of the barrel. During this unstabilized flight, the bullet will apparently upset and not overpenetrate bodies and/or other objects struck.

Where did you come up with that one, that one gets the ding ding ding ding ding ding we have a winner over here award...........

I can assure you a 5.56mm projectile is very much stabilized by the rifiling from bore exit upto taget impact.........

kozak6
May 22, 2008, 05:43 PM
If their budget is limited.

Shotguns are significantly cheaper.

Dragunov54
May 22, 2008, 06:49 PM
12 ga slugs work well to bust locks and hinges. SMGs don't

ISC,

It is true that SMG's are not practical for breaching applications. However, a standard 12 ga slug used for breaching locks and hinges can be very dangerous for the operator and team members due to mass fragmentation of an exploding slug when impacting upon metal locks and hinges. A breacher wielding a shotgun carries a breaching round called "Hatton". It is a fast disintegration material similar to filling material a dentist would use to patch your teeth.

Stevie-Ray
May 22, 2008, 07:33 PM
With most of the .223 ammo screaming along at more than 3,000 fps, the bullets are prone to flying apart when they impact virtually any medium. Even FMJ ammo breaks up dramatically when it hits sheetrock at these velocities."So.....I might be better off using my PLR-16 for HD than my USP45C?

ClassicSWC
May 22, 2008, 07:43 PM
My machine gun use is limited, having fired a tommygun and a Mac-10 in Vegas and a worthless CAR-15. My shotgun experience is substantially greater than that. If you need to clear a room, I'll take the machine gun. One caveat though, you need to practice. The Mac-10 is a handful, the tommygun not so much so. Once you get the hang of them, they'll spit more lead than a shotgun. Figure for the Mac-10, 20 rds a second.

tplumeri
May 22, 2008, 07:45 PM
seems like a semi auto 12 gauge would be the best "all around" (?)

08 Cayenne
May 22, 2008, 08:40 PM
I've only shot a machine gun twice
Indoors up close I'd prefer Betty Lou, (Ithaca 12 gauge) with #00 buck

HKuser
May 22, 2008, 08:42 PM
A bullet that is unstable does not get more stable as it flies, stability deteriorates. I also find it hard to believe that a 9mm with outdo a 5.56mm on penetration. Look at vest ratings, 5.56mm resistance is 2 levels above 9mm.

JollyRoger
May 22, 2008, 09:55 PM
I know it sounds counterintuitive, but the 5.56 DOES stabilize in flight, about 50 feet out, IIRC. It has to do with the geometry of the bullet, long and thin with a very small radius relative to length, and the fact that no bullet ever centers perfectly with the center of the bullet lined up with the center axis of the bore. That's why they need stabilization in the first place. The difference with the 5.56 as opposed to others is like the difference between a spinning football and a long spinning steel rod: the rod wobbles for a bit, then damps down as the rotational forces take hold.

Anyway, that is what the guys from our firearms unit, who want to eliminate subguns and shotguns in favor of M4's for everything, told me. Actual shootings seem to bear this out: within 50 feet the bullets stay in what they hit, further out they can drill a steel plate.

I'd be happy to entertain alternate explanations, though, for entertainment value if nothing else.

James K
May 22, 2008, 10:22 PM
On the SMG vs shotgun, I will tell this one on myself. When I first got a Thompson, I had the same discussion with a friend who had an Auto 5. So we set up five silhouette targets at a range of, I would guess, seven yards, in a line about a foot apart - bad guys ganging up on us.

I put a 50 round drum in the Thompson and made like Al Capone, just like in the movies. The "trench broom" and all that stuff.

Then he upped with the Auto 5, and rattled off 5 rounds of 00 Buck.

The result? I had gotten one (1) shot in the edge of the first target. Period. No need to change targets. He put 9 slugs into each target and did it faster than I had fired 50 .45 rounds.

Later, I learned to use the Thompson better, but that little session proved to me that there is nothing about a subgun that will make holes magically appear in a target.

Jim

Boris Bush
May 22, 2008, 10:24 PM
JollyRoger

Well then, the guys on you units firearms team needs some learning. Where did they get that "information" from?

They have it backwards. The projectile de-stabilizes after impact. When M855 ball is fired into flesh it will in 2-5" of penetration begin to tumble as I call it, guys who like big words will say yaw. At a velocity of 2700 fps or faster M855 ball will seperate at the point between the steel and lead core, causing fragmentation. The fragmentation velocity is gone at about 90 meters of travel and will still tumble in flesh but will not reliably fragment. When it hits flesh and tumbles and does not break apart it still makes for a nasty wound.

Even when I used M955 ball that has a hardened tungsten core that still has a air pocket will still tumble in flesh in 2-5" of penetration but will not fragment due to the hardness of the core. It worked spectacular up close when we had to shoot through cars that would destroty the M855 projectile. The M955 penetrated, and still "worked" with wicked reliability.............

I would like to talk to your firearms unit guys, they have it all backwards. I can give first hand experience on how the 5.56 works from contact to just over 200 meters.

w_houle
May 22, 2008, 10:45 PM
12ga 00 buck one trigger pull vs smg. 1 shot 9 bullets vs 9 shots 1 second?

JollyRoger
May 22, 2008, 11:08 PM
Okay, Boris Bush, I don't want to keep hijacking this thread, so this will be my last post on the subject. A quick search turned up some authority to back me up regarding stabilization at distance, see below. I do not dispute that the 5.56 tumbles on impact up close, in fact that was what I was saying, at least in part. Anyway, this guy puts it a lot more scientific than I can, seeing as how this was background for his patent application.

http://www.patentstorm.us/patents/6973879/description.html

In addition to the tendency of the M855 and the M193 projectiles to breakup at short ranges upon entry into the target such projectiles have limited lethality or incapacitation effects at longer ranges due to the high Sg or gyroscopic stability factor as a result of the mass moments of inertia of the high-density core filler material and the low length to diameter ratio. Projectiles such as the M855 or the M193 if they do not break up upon entry into the target as represented by 10% Ordnance gelatin they will typically turn over once (yaw 180 degrees) and continue to move through the target base first.

Best I can do right now.

P220C
May 23, 2008, 10:30 AM
"I have seen fmj .223 bore a clean hole in 1/4" steel plate, and eat up a brick wall behind it. I don't think 9mm will do that!"

No, but the ammo that will go through plate and brick is hopefully not the same ammo an entry team is using. I would imagine they are using somethink light and frangible (sp?).

barnes has a bullet out right now called the 'varmint gernade" It fully franges going through a grape.

As for why a vest is rated for 9mm or 5.56 is that a 5.56 is much pointier, and the projectile (even a frangible one) will "needle" through the lower rated vest moreso than a blunt 9mm or 45 cal. Once through the frangible round begins breaking down.

This was part of the design consideration for FN's five-seven AP rounds.

Boris Bush
May 23, 2008, 10:44 AM
JollyRoger


We are saying the same exact thing. The problem is you think the bullet is not stabilized when it exits the bore, and somehow stabilizes itself after a certain distance is traveled. I have no clue where that information came from and how it got to you. The 5.56 projectile is very much stabile after bore exit. The rifiling ensures that. I think you are mistaking velocity for unstabile. It is its fastest closest to the bore and the faster it is 2700 fps and faster the M193 and M855 ball rounds will fragment. The faster M193 will do it farther btw, about 200M compared to 90M for M855.

AK103K
May 23, 2008, 11:31 AM
"My machine gun use is limited..."
This is probably the main reason many think the shotgun is better, they have no real experience or training with a SMG to know their advantages.



....that there is nothing about a subgun that will make holes magically appear in a target.
Very true, but with just a mag or two of proper training, you can teach small statured adults and even small children to shoot a pistol caliber SMG effectively. Many people have difficulty with a 12 ga, especially using full house loads.

Subguns, however can go from a multi-round weapon to a precision weapon out to moderate distances simply by going to semi-auto, and the ones that fire from a closed bolt are usually very accurate...
This is one of the biggest advantages to the SMG. They offer a more useful weapon over a broader range, and one that is more easily and quickly reloaded. They are also usually in a much handier and easily wielded package.

12ga 00 buck one trigger pull vs smg. 1 shot 9 bullets vs 9 shots 1 second?
One shot of 00 buck or a two to three shot burst of 9mm, the effects are the same. Solid, multiple instantaneous hits shut the CNS down. You dont need nine 9mms. Stretch the range just a little, say out across the yard at 30 yards or so, how many rounds of 00 buck will it take and with what consistency can you make those shots?

Personally, I keep #1 buck in my shotguns. Using 2 3/4" shells, 00 usually carries 9 .33 caliber pellets, where #1 buck will carry 16 .30 caliber pellets, usually with a heavier load to boot. Your longer range hit probability goes up where its needed in rounds that are quickly running out of steam.

Ruthless4christ
May 23, 2008, 07:25 PM
first let me say this.

I own several full auto weapons, and have fired alot rounds out of alot more. Mostly AK and mac 10

however unless you are extremely trained to fire an AF weapon, and think you are going to be in a mogadishu (or maybe camden NJ:D) like setting where you will be carrying about 200 rounds of spare ammo, you need to think about sticking to the shotgun.

in my opinion the combat uses of a good 12 gauge are alot more vast then a maching gun, not to mention that a full auto weapon is very very very hard to use well.

AK103K
May 23, 2008, 07:44 PM
not to mention that a full auto weapon is very very very hard to use well.
I've got a couple myself and have been shooting things like them since I was about 8, and have never found this to be the case, especially with the pistol caliber guns. Hell, my kids were shooting my MP5 at 5 years old with no troubles, so they cant be all that hard. :)

One thing I've found over the years with owning and shooting select fire/full auto guns is, there are a lot of people who claim to be "trained" in their use, who have no idea as to what they are doing with one in their hands. A lot of these people were supposedly combat vets too. They all talk a good show until you get them out shooting, and then their skills seem to have wandered off.

Once you know the technique, and its very easy to learn, if the student is willing, you can shoot pretty much anything with little trouble and good results.

Deaf Smith
May 23, 2008, 09:45 PM
A bullet that is unstable does not get more stable as it flies, stability deteriorates. I also find it hard to believe that a 9mm with outdo a 5.56mm on penetration. Look at vest ratings, 5.56mm resistance is 2 levels above 9mm.

HKuser,

The 5.56 shatters easly. When it hits walls it fragments. But because of it's velocity, when it hits Kelvar it goes through (kelvar is not solid like a wall, it gives some.) The 9mm will usually not shatter on a wall, and hence more penitration.

Kelvar Threat IIIa vest will usually stop something below 1500 fps or so. Velocity above that is when the slugs start penitrating.

nemoaz
May 24, 2008, 03:33 AM
Kelvar Threat IIIa vest will usually stop something below 1500 fps or so. Velocity above that is when the slugs start penitrating.It's not just velocity. Smaller diameter rounds have a much easier time penetrating the woven strands of kevlar. Any shotgun slug will be defeated by any modern body armor level IIIA or better.

mellow_c
May 24, 2008, 04:18 AM
First of all, I think it was well covered about how the shot gun is tactically better in certain situations vs a sub machine gun. Also, in other situations the Sub Machine gun is better. That's probably why Alot of SWAT teams carry them both.

As far as the bullets fragmenting on impact. Havent you all seen the Myth Busters episode where they see how far into watter a bullet will still be deadly?

They find that the higher speed rounds fragment basically on impact, making them lethal only about a foot into the watter, they even tried shooting a .50 cal sniper rifle with the same effect. Where the 9mm they shoot had the greatest lethal travel under watter, something like 4 or 5 feet. There for, also like said above, a long distance shot with a high speed bullet will slow the bullet down, allowing for greater penetration... where a close range shot, in which case the bullet is going much faster, it will fragment sooner upon penetration. makes sense to me :rolleyes:

I'd also go with what was said above, that the semi auto shotgun seams to be the best of both worlds. It's almost like cheating:D But, it will never give you that precise shot of an SMG... there for SWAT caries them both

James K
May 24, 2008, 06:21 PM
"The problem is you think the bullet is not stabilized when it exits the bore, and somehow stabilizes itself after a certain distance is traveled."

Maybe the 5.56 is different (I don't think so), but that is the case with .30-'06 and .308. The bullet leaves the bore with a distinct yaw and doesn't "go to sleep" as the old-timers put it, until around 30 yards out. If you want to see, it is easy, just set up targets a foot apart from near the muzzle to about 10 yards out and you can see the keyholing on the closest targets decline on the farthest. That is why penetration tests show that less penetration occurs close to the muzzle than at, say, 50 yards.

Jim

Dwight55
May 26, 2008, 07:11 PM
I would only look at the guys I saw in VietNam going into the bush. If he was looking to be point man, . . . many would exchange their M16 or M14 for shotguns, . . . and fill up every last pocket with 00 buck. SMG's were few and far between where I was.

And those shottys were bottom loading, bottom ejecting Steven/Savage rascals that only held 4 to begin with.

To me there is a lesson there, . . . knowing you can positively drop 9 pellets where you point the shotty, . . . and not knowing for sure where the 20 will wind up on rock N roll out of the 16 or 14. I would suspect that all SMG's would be the same.

Anyway, . . . my $.02

May God bless,
Dwight

LeadFistExpress
May 27, 2008, 04:13 PM
I have found two websites that support the notion that a bullet is not perfectly stable upon exiting the barrel. The first one states that on short ranges you can see keyhole impacts in the target. It states that it can happen when the round has not had enough time to stabilize from an initial disturbance. (http://anarchangel.blogspot.com/2007/01/stabilization-mythology.html)

Now, what could this initial disturbance be? According to the second website, the exiting gases from the muzzle "cause or contribute to three unwanted effects: muzzle flash, recoil/muzzle lift and interference with projectile stability." (http://www.patentstorm.us/patents/5596161/description.html) While I would never have believed it, it does appear that a 5.56 round, along with just about any other round, can have a bit of wobble when it exits the barrel, caused mainly by the muzzle blast. It will stabilize itself with the aid of the spin imparted by the rifling. I do not think it has anything to do with the ability, or lack thereof, to penetrate a wall or fragment upon impact, but I now believe that it is not perfectly stabilized upon exit.

David Hineline
June 3, 2008, 12:17 AM
Shotgun at close range across the bedroom nothing beats it. Stretch that distance out to 7yds and the pattern is spread and not target specific enough. The subgun can easily do multiple hits on full auto from point blank to 50yds. Past that the selector should be put on semi auto.

Those who say a subgun climbs just don't know how to handle a subgun, I am not taking about a machine pistol with a wobbly stock like the MAC but a subgun.

http://myweb.cableone.net/uziforme/m16-9mm.wmv

LanceOregon
June 3, 2008, 11:42 AM
I think that it is a major mistake here to assume that law enforcement is primarily using FMJ .223 ammo. If you look at the law enforcement product lines of the major ammo makers, you will see that the vast majority of their .223 products for LE use are using rather fragile bullets.

Federal's Law Enforcement Tactical Tru product line uses Nosler Ballistic tips. The new Federal Tactical Lite Open Tip Match uses very lightweight hollowpoint .22 bullets weighing only 43 and 50 grs.

Hornady's Law Enforcement TAP product line has .223 loads using their 55 and 60 gr VMAX varmint bullets, which are well known for being fragile.

Winchester's .223 Law Enforcement product line includes ammo using their soft point PowerPoint bullets, the Ballistic Silvertip ( a specially coated Nosler Ballistic Tip ), and some hollow point designs.

These products are all being marketed to Law Enforcement as having the benefit of very low risk of over penetration that could harm innocent people.

.

Erik
June 3, 2008, 01:12 PM
"I think that it is a major mistake here to assume that law enforcement is primarily using FMJ .223 ammo. If you look at the law enforcement product lines of the major ammo makers, you will see that the vast majority of their .223 products for LE use are using rather fragile bullets."

"These products are all being marketed to Law Enforcement as having the benefit of very low risk of over penetration that could harm innocent people."

I agree, adding that I'd be surprised to find any FMJ issued to US LEOs for general purpose use.

Chui
June 3, 2008, 09:03 PM
Frangible ammo is used to breach doors and frangible .223 Remington WILL PENETRATE SHEET ROCK.

I think that JHP .223 Remington will penetrate less than JHP pistol ammo. From what I've personally experimented with FMJ .223/5.56 will outpenetrate JHP through some mediums - including sheet rock.

:confused:

Socrates
June 7, 2008, 04:27 AM
Mac 10: 32 rounds of 230 grain ball, on target, with one pull of the trigger, in less then 2 seconds? That's a ONE BORE going off on you, with no recoil on the shooter. I've often thought that would be a good bear deterrent, just by the sheer volume of lead hitting, not to mention ball isn't bad at penetration.

A mac is MUCH easier to carry around a house, shoot from awkward angles, and, it has sites the equal of most shotguns...

T. O'Heir
June 8, 2008, 01:28 AM
"...When I first got..." Exactly. Shooting an SMG, well, is no different than shooting anything else. It takes training and practice to control it. Lots of people think a shotgun doesn't need to be aimed either. A Chopper isn't the best example of an SMG either. As slick as they are.
"...5.56 FMJ bullets will disintegrate upon impact with just about anything..." No they won't. .223 varmint bullets will, but not a military ball round. It's all about bullet construction.
"...until around 30 yards out..." More like 300 yards. A .30 calibre bullet penetrates better past 300. Takes that far to fully stabilize.
"...frangible .223 Remington WILL PENETRATE SHEET ROCK...." So will a screwdriver.
"...32 rounds of 230 grain ball, on target..." Only by a very experienced shooter. Emptying the mag with one trigger pull is really poor use of an SMG.
"...would be a good bear deterrent..." Yogi would get extremely annoyed if you don't hit him right. If he's within 100 yards and charging, you're toast.
SMG's are used by SWAT type cops because they look cool. They're are great things for very close quarters shooting. A shotgun, though, is far more intimidating. Personally, I would let cops have either. At least, up here. Minimal training and little experience shooting anything.

JollyRoger
June 8, 2008, 09:10 AM
This may be a slightly different twist on the subject, but still valid in choosing shotgun vs. smg: when dealing with law enforcement in urban areas, one always has to consider what happens when an officer misses in an urban setting - law enforcement hit ratio is somewhere around 17%,IIRC. This is where the shotgun really excels. Shotgun pellets are spherical, one of the worst aerodynamic shapes because travel through the air generates a vacuum on the rear side. This means you get real power up front, but velocity drops off quickly. You don't get quite as good of a drop-off with slugs, but with their large frontal area compared to mass, they drop off pretty well, too. By comparison, subgun rounds and 5.56 rounds travel a LONG way, exposing innocents to risk, especially in outdoor shootings where there are no walls to slow them down. Simple geometry shows your area of risk is a circle determined by the square of the radius (that being the distance a bullet will travel in free flight before it hits ground.) Also, pump guns which are commonly issued can handle low velocity buckshot which further reduces the risk to innocents: while barricade penetration is affected, terminal effect on soft targets is not affected too much because you are not relying on velocity to expand a hollowpoint.

Socrates
June 8, 2008, 10:35 AM
Macs are actually very heavy for caliber, at least the 45 ACP version, and, are therefore rather easy to shoot. Recoil like a 22. When you add either a silencer or barrel extension, piece of cake compared to a M14.

They do have a high cyclic rate of fire, between 600-1200 rounds per minute, and, this combined with a very stiff trigger, makes it difficult to burst fire well.

Chui
June 8, 2008, 01:43 PM
"...frangible .223 Remington WILL PENETRATE SHEET ROCK...." So will a screwdriver.

And your "point" would be?????

I've not heard of people maimed or killed by screwdrivers being hurled at someone in adjacent rooms. :rolleyes: