Wanted: CT/MT Stats for Mac SMG

[kaladorn]

Originally posted by Corejob:
The reality of modern combat is that there is very rarely any kind of precision shooting.

Moreso in some armies than others...

It is unrealistic to expect hit probability to increase because the weapon is made more accurately.

Statistically, only up to a point. A weapon that was very inaccurate would cause results to get worse. But better effectiveness, in a large sample that blends marksmen and SF with lots of average guys and gals, is not a thing you get lots of just by getting a more accurate weapon.

Ideally, the rifle should be designe so as to compemsate for less than ideal combat marksmanship. Hitchman advocated either a salvo firing weapon, or one that fired a burst at a high rate of fire.

Metalstorm technology offers an interesting approach to some of these problems, and also offers benefits in terms of round selection.

The problem is that most shooters are used to thinking in terms of semi-automatic fire and shooting at fixed targets at known ranges. Real combat is about firing busts of automatic fire at moving targets at unknown ranges that use cover and shoot back.

It *CAN* be about this. It can also be about sniper/counter sniper. And if you don't have some accurate weapons with long reach with you, and the enemy does, you won't be happy.

Bursts are common, but generally anytime I've seen anyone do "full auto" at any kind of range, they've had poor results and expended a lot of ammunition. You can, if you have a large belt, do some 'walking on target'. But if you're firing from a mag-fed weapon, that's a recipe for a lot of sound a fury that signifieth nothing.

OTOH, a lot of people have been killed by semiautomatic weapons....

Not disagreeing, but just pointing out that any generalization has inherent flaws.

Personally, I think that it is time to totally rethink the concept of the rifle as a general infantry combat weapon. I'd like to see something like the Steyr ACR or prhaps eveen the HK CAWS loaded with long range ammunition like SCMITR flechettes.

If the flechettes ever actually live up to their promise. I've intermittently seen them looked upon as incredibly dangerous and incredibly inadequate. I think to date they have yet to live up to the incredibly dangerous label in practice on any large scale.

Replace the rifle with a salvo weapon that is leathal to 500 meters and fires a pattern of projectiles to compensate for aiming errors that happen under the stress of combat.

Which is fine, if all you're going to do is fight all out wars where you don't give a damn about civilian casualties. If you have to shoot around civilians or if you have to engage targets and can't afford much collateral damage (common in OOTW if your national flag isn't the stars and stripes.... up North here, we spend a lot of time worrying about what to do on UN missions and NATO missions and such where you may well NOT be able to deploy your firepower but you still need to be effective).

I still think there is a place for the rifle in the Infantry unit - as a specialist weapon where precision fire is required, and issued to that rare creature that can deliver that prercision fire under the stress of combat.

I think before they do away with the infantry rifle, they'll have ways to control the mental state of the combatant (already on the horizon, early models already tried out) to perhaps even reduce or carefully meter stress.

Rifle practice continues to be deemphasized because it is becoming more and more irrelavant in modern mechanized combat. Only something like 1 or 2 percent of casualties are produced by small arms. Rifles have become weapons of self defense, used to supress the enemy while you radio for a fire mission.

Modern mechanized combat is becoming more and more irrelevant itself (to a point) in these days of peace stabilization, peacekeeping, humanitarian interventions, CT operations, aide to foreign powers, OOTW, etc. In these scenarios, artillery and air strikes are often not an option. So you'd better have weapons in your arsenal that you train with that can be deployed very selectively to root out snipers, individual insurgents, etc. from among enemy populations or in urban areas with lots of non-combatants around.

My fear if you have everyone carrying a full auto shotgun with flechettes, you're screwed in this kind of mission.

Western armies realize this, and spend less and less on infantry weapons and infantry training, seeing those dollars as better spent on the weapon systems that really do matter. Personally, I think they do so at their peril.

On that we agree. It is still the guy on the ground who holds that ground over the longer term. In those kind of ops, he may well find he has no time to call for arty. If the nutbar with the bomb comes a runnin', you'd better hope he still knows how to shoot and do so fast and accurately.

My own aside:
According to sources on the infantry board, about 90% of all infantry combat in Iraq is at 100 meters or less. Primarily this is due to the urban nature of the combat. Also, at longer ranges, there is a tendency to use vehicle weapons or other assets.

And FIBUA/MOUT/OBUA is getting more and more common as it isn't just about bombing people flat anymore.

And vehicles and marksmen-in-squad (the French got this right) contribute a lot in these situations, to be sure.

Bringing this all the way around to Traveller, the canon weapons (at least from CT) are built around the old and outmoded concept of infantry combat still taught today. The gauss rifle has the potential to be an ideal combat weapon as Hitchman suggested. Give it a lighter projectile to reduce recoil, up the velocity to bring up lethality and give it and extremely high rate of fire.

Gauss rifle an autoshotgun/autoflechette gun seem likely candidates. The ACR seems like the last gasp of the projectile weapon, a lot like the OICW. After that, it'll be a mix of gauss area fire weapons and gauss precision fire weapons. And some plasma guns thrown in for anti-vehicle possibly.

Every time the soldier pulls the trigger, he isn't sending one large, highly lethal projectiles down range. Instead, his is firing a cluster or projectiles, each one is more than sufficiently lethal on its own, but moving as a cloud of projectiles over an area, there is a significantly increased probability of a hit, even against a fleeting target making use of cover and concealment.

And most of the time, a wound is sufficient.

Spinkle in a few marksmen with more accurate, sniper type weapons to attack target of opportunity and you'd have a nice lethal mix.

That would more or less be the way to do it.

I always thought an infantry section with a fire base (support weapon gunner/assistant gunner), two manouver elements of 4 men (breaks down into pairs, which I like better than the 3 man version), and a marksman (or marksman plus spotter) makes for a nasty combination of suppressive and precision fire with the riflemen being intermittently either (ideally, they'd have the capacity to deploy either type of fire by round selection - everything from small grenadelets to shotshell to reasonably accurate slug).

 

[Uncle Bob]

Metalstorm has limitations. So far no-one has made it work with a spire point bullet, which limits it to grenade launchers and pistols/SMGs.

Precision fire serves several purposes. Probably the most important being that it increases the soldiers' confidence in their weapons. It is also good for them to know that, if they keep their heads, they can kill snything theycan see.

High ROF and salvo weapons are indescriminate. o far I haven't seen a system that can incresee the chance to hit all the way fom 10-300m. If it gives you a better chsnce at 25m, dispersion makes it useless st 250m. Likewise, a superfast burst like the G11 or Akaban might as well shoot a single bullet at close range.

The OICW/SABR/XM25/XM29 offers a different approach. You can fire time fuse HE, or point detonsting HEAP, or less-than-lethal payloads. No APERS yet but it won't be long.

 

[kaladorn]

I said MetalStorm had potential, not that it didn't have engineering issues at present

The ability to use it for the weapons it does currently work for (which, BTW, also includes IIRC some sort of CIWS for point defence, or at least there was some work done on one) is where the engineering will be applied to solve the problem.

Besides, it makes for a good sci-fi gun idea.... and isn't that really what this all boils down to?

 

[Todg]

Originally posted by kaladorn:
If the flechettes ever actually live up to their promise. I've intermittently seen them looked upon as incredibly dangerous and incredibly inadequate. I think to date they have yet to live up to the incredibly dangerous label in practice on any large scale.

Which is why I specified SCMITR flechettes. These use cutting as the casualty producing mechanism, and in live animal tests (isn't the US army naughty?) conducted in the 1970s showed that they were extremely lethal. See the thread on the disposable shotgun. I posted a photo there.

The jury is still out on the rifle fired (high velocity) flechette. Fackler pooh-poohed the lethality of the flechette, but he was looking at the performance of flechettes from beehive artillery rounds. To date there has been no (published) tests of rifle flechette performance on either animals or ballistic gelatin. There are runmors that Steyr tested their ACR in gelatin and found that the flechettes performed well, deforming and twisting and generally making a mess of things. They have not published any data.

 

[Todg]

Originally posted by kaladorn:
I said MetalStorm had potential, not that it didn't have engineering issues at present

The ability to use it for the weapons it does currently work for (which, BTW, also includes IIRC some sort of CIWS for point defence, or at least there was some work done on one) is where the engineering will be applied to solve the problem.

Besides, it makes for a good sci-fi gun idea.... and isn't that really what this all boils down to?

I think that the problem is we are still thinking in terms of guns - weapons that fire a projectil (or beam) that creates a linear danger space. The US army is already moving beyond that concept. The idea behind the OICW is to creat a danger zone in the area of the electronically fused explosive projectile. This represents a new way of thinking.

The next step is even smarter ammunition - perhaps even homing round. Micro electronics could change the rifle the same way it killed the anti-tank gun in favor of the ATGM.

Metal storm is really nothing more than a new way to shoot bullets. It's not even clear if it is really an advance.

 

[kaladorn]

Beg to disagree.

1. It allows multiple rounds to be available at the flick of a button - something most service pistols or rifles can't currently manage.

2. It comes closer to your 'cloud of projectiles' than you imagine, or could. All you'd need to do is arrange multiple barrels with a slight ofset.

3. For something like CIWS, where a 'wall of lead' is part of the defence, it has RoF that far exceed conventional weaopns.

4. It can probably be used with smart bullets too.

 

[Uncle Bob]

Originally posted by Corejob:
Which is why I specified SCMITR flechettes. These use cutting as the casualty producing mechanism,

The picture is a little unclear, but I remember the SMITR as a wide, flat projectile. This will reduce the number of projectiles that makes flechettes attractive in this context.

The jury is still out on the rifle fired (high velocity) flechette.... There are runmors that Steyr tested their ACR in gelatin and found that the flechettes performed well, deforming and twisting and generally making a mess of things. They have not published any data.

One story is that since the Steyr flechette would be supersonic in tissue (1500 m/s+) and muscles and organs aren't pierced so much as they shatter like glass. Maybe.

Originally posted by kaladorn:
Beg to disagree.

1. It allows multiple rounds to be available at the flick of a button - something most service pistols or rifles can't currently manage.

But you need a seperate barrel for each choice of ammo. That gets heavy, fast. And the balance and handling suck.

It can probably be used with smart bullets too.

But not with high velocity projectiles, at least not the current version. I like the Australian Advanced Individual Combat Weapon (see Multiple Effects Weapon System) though.

 

[Todg]

Originally posted by kaladorn:
Beg to disagree.

1. It allows multiple rounds to be available at the flick of a button - something most service pistols or rifles can't currently manage.

I'm not sure what you mean by this. More than one round per pull of the trigger? Military rifles have a selector. Different kinds of ammo. This has proven to be unimportant. Convention restric the type of ammunition you can use. Most armies have even moved away from multiple types of ammo, replacing ball and AP with ammo that performs both roles (forex M855).

Also, multiple types of ammo carried simultaneously means a larger ammo load, which may or may not be a good thing on the weapon irself.

The fact that it has no moving parts seems moot, because the best military assault rifles are tremendously reliable. And to reload them, you only replace cartridges and a relatively inexpensive moagazine. In the case of MetalStor, you reload by replacing the barrel - a precision made, rifled tube that must withstand the chamber pressures generated by modern ammunition, around 54,000 psi for 5.56x45mm. While MetalStorm may be able to do this, such barrel/magazines will not be cheap, light or as convenient as current box magazines. When you are equipping several tens of thousands of soldiers will ammunition, cost and weight add up.

2. It comes closer to your 'cloud of projectiles' than you imagine, or could. All you'd need to do is arrange multiple barrels with a slight ofset.

Yes, perhaps. But there are concerns that the dispersion characteristic of MetalStorm will be too large for that role. Because the rounds are stacked, each round transits a different length of barrel and probably have a different velocity. Also, the design precludes the use of certain projectile types.

3. For something like CIWS, where a 'wall of lead' is part of the defence, it has RoF that far exceed conventional weaopns.

True. But that is not relevant to the discussion of the MetalStorm as a rifle.

4. It can probably be used with smart bullets too.

Perhaps. See above. Because the the nature of MetalStorm with it's stacked ammunition, it is unlikely that each round fired from the same carrier with have ballistics close to the preceeding and succeeding rounds. This introduces yet more complexity into smart ammo.

The chief advantages of MetalStorm are simplicity of operation (no moving parts) and high rate of fire.

But, it is really nothing more than a new form of bullet launcher. Just a faster one without a lot of mechanical complexity. That may have some virtue in certain applications - see my own idea of a disposable shotgun, something MetalStorm would be perfect for.

If MetalStorm proves feasible as a smart ammo launcher (like the OICW) it will represent a radical change in firearms, but only because of the ammunition. The MetalStorm gun is still a bullet launcher that creates a linear danger space, in exactly the same fashion as current weapons - merely faster and simpler. Unlike the PICW, it cant shoot targets behind cover, inside building or down in fox holes.

If MetalStorm is able to support 'smart ammunition' it will probably be an excellent platform to use. To date, MetalStorm is a solution looking for a problem. It has generated considerable interest, but no one is rushing out into the field. It is likely to find a place in certain niches, but it is extremely doubtful that it will replace conventional firearms in any large way, regardles of Mr. O'Dwyer's hopes or marketing materia.

Everyone thought that caseless ammunition was the future too, and in the end, nobody bought the HK G11.

 

[Todg]

Originally posted by Uncle Bob:
The picture is a little unclear, but I remember the SMITR as a wide, flat projectile. This will reduce the number of projectiles that makes flechettes attractive in this context.

Not necessarily. Standard 2 3/4" high base 00 buckshot shells contain 9 .33 caliber balls. By contrast, the same shell can hold 14 SCMITR flechettes. The flechettes are much more lethal, and can defeat aramid fiber vests and steel helmets out to over 500 m.

One story is that since the Steyr flechette would be supersonic in tissue (1500 m/s+) and muscles and organs aren't pierced so much as they shatter like glass. Maybe.

Unfortunately this is not the case. It was originally believed that projectiles that exceeded the speed of sound in tissue (1450 m/s) would cause disproportional wounding do to effects of transonic drag. Such projectiles would cause shallower wounds with much greater lateral damage, and it was even believed that organs would be 'shattered' by the shockwaves. This theory had it's origin in experiments carried out by Charters and Charters ("Wounding Mechanism of Very High Velocity Projectiles", Journal of Trauma 16, 464-470, 1976)

More detailed research carried out By Fackler, Bellamy and Malinowsky ("Wounding Mechanism of Projectiles Striking at more than 1.5 km/sec", Journal of Trauma 26, 250-254, 1986) showed that the Charters conjecture was incorrect. Facker and co. fired a large number of projectiles into ordnance gelatin at velocities up to 2 km/sec and found no change in wound profiles over the velocity ranges.

To be sure, the higher velocity projectiles did more damage due to higher KE, but there was no significant change in the pattern of wounds between sub sonic and supersonic velocities in tissue. Given enough KE dumped into tissue, organs will shatter, but this is not an artifact of extremely high velocities.

It should be noted that I shared the same belief about hypervelocity projectiles until being made aware of Fackler's research in this area.

I like the Australian Advanced Individual Combat Weapon (see Multiple Effects Weapon System) though.

I note that this weapon uses a conventional AUG, and only uses MetalStorm technology for the launcher portion of the weapon. This seems a rather elegant solution compared to the OICW.

 

[Uncle Bob]

Originally posted by Corejob:
Not necessarily. Standard 2 3/4" high base 00 buckshot shells contain 9 .33 caliber balls. By contrast, the same shell can hold 14 SCMITR flechettes. The flechettes are much more lethal, and can defeat aramid fiover vests and steel helmets out to over 500 m1

I figure there is a 50/50 chance of getting no hits at all at 145m with 9 buckshot, 180m with 14 SCIMTR, 210m for 20 flechette. Not as bad as I thought.

To be sure, the higher velocity projectiles did more damage due to higher KE, but there was no significant change in the pattern of wound between sub sonic and supersonic velocities in tissue. Given enough KE dumped into tissue, organs will shatter, but this is not an artifact of extremely high velocities.

Much obliged.

 

[kaladorn]

Fair points, Corejob.

However, I think the availability of different ammo will be of great use to police, if no one else. The ability to have say a rubber slug, a tranq round, and some sort of AP round in case your perp is wearing BA, could be very handy. And since they don't fire that much ammo in an engagement (usually less than 15 shots, usually only a couple or three), then having the ammo selection may matter a lot.

As to ammo selection for conventional military, there are times one might like a hollowpoint bullet instead of an AP, but it isn't the same pressing issue exactly. And there would of course be personal and systemic logistic issues.

Perhaps something like a flechette firing gun combined with a metalstorm GL would be a good combination.

Metalstorm is a bit of a solution with a limited market. CIWS, police uses, GLs, there are a number of places where it would be useful. And yes, the types of ammo it eventually can fire will matter. But the same is true of the OICW - if it didn't get smart grenades, it wouldn't be much different (except for being less effective) than the existing rifle/GL (well, having more than one grenade on tap is nice).

As to the variable velocity issue, there are two approaches: 1. the problem is an engineering one that I understood could be solved by varying propellant loads or something of the sort and 2. variable velocity might result in variable round trajectories, thus giving some of the dispersion that would increase the odds of a hit.

Surely, it isn't the be all end all. But it has places it is interesting to imagine it used, and if we use it as a sci-fi weapon, we can posit engineering solutions developed to some of the real world problems.

And as to caseless ammo, the logic for it is essentially still compelling. I can only see engineering issues as being problematic, and it may well yet be perfected.

 

[Todg]

Originally posted by kaladorn:
Perhaps something like a flechette firing gun combined with a metalstorm GL would be a good combination.

MetalStorm seems ideal for this kind of application. As I noted with regard to the disposable shotgun, it is ideal for single use applications, or ones where precise accuracy are not a requirement.

I still wonder about cost effectiveness, where you are basically replacing barrel elements. This may not be the case in all applications. The linear layout of MetalStorm may prove to be ideal in some applications. If one consideres the tubular magazine of the shotgun, MetalStorm looks ideal.

As to the variable velocity issue, there are two approaches: 1. the problem is an engineering one that I understood could be solved by varying propellant loads or something of the sort

But then you loose the mass manufacturing advantage that you get when turning out thousands of identical items. In the case of something like the smart grenade, you'd probably compensate at the electronic sight.

and 2. variable velocity might result in variable round trajectories, thus giving some of the dispersion that would increase the odds of a hit.

It's unfortunate that MetalStorm doesn work well with long ogive projectiles (an issue with the obturator I'm told) or very high pressures. I'd like to ser a serial launched flechett rifle that fired a 5 or 10 round burst at 3-5,000 rpm and 2,000m/s. Boy howdy, that would be slick.

Surely, it isn't the be all end all. But it has places it is interesting to imagine it used, and if we use it as a sci-fi weapon, we can posit engineering solutions developed to some of the real world problems.

Agreed. It certainly has many potential applications for Traveller weapons. I particularly like the idea of disposable weapon using metalstorm. The whole gun (perhaps minus the electronic sight) becomes an expendable unit. It's a very different way of looking at small arms. Your assault rifle or grenade launcher because like a LAW. Shoot and toss. No concerns about wearing it out or anything.

[/quote]
And as to caseless ammo, the logic for it is essentially still compelling. I can only see engineering issues as being problematic, and it may well yet be perfected. [/QUOTE]

HK had virtually perfected it in the G11. It was compelling, but not compelling enough. The advantages have to be large before an army replaces a functional system.

In the case of Traveller, you don't necessarily have that problem. Some army might equip itself with MetalStorm type weapons because they don't already have an existing platform.

I am already considering yet another MetalStorm based weapon, the 'calliope gun'.

Consider the Colt Defender shotgun, and already awesome close combat weapon.

Now add MetalStorm so that each barrel has 5 or more stacked rounds (in 8 barrels for 40 rounds). A very intimidating, large capacity weapon. The shotgun is an ideal platform for MetalStrorm because the shogun operates at low chamber pressure and the payload can be put into a relatively blunt capsule.

 

[Straybow]

I've always thought caseless is a bad idea. It works fine if the rounds are contained in clips and protected from the elements.

As soon as you have loose rounds they get dirty, wet, chipped, etc. Now you've got fouling and misfire problems.

With caseless you also have supply problems. Two manufacturers using their own powder formulas can have the same ballistics by controlling the amount of powder in the shell. For caseless I guess the powder part could be hollow to allow for variable sized charges with different powders. That would require more engineering and testing than regular ammo charge design.

 

[mike wightman]

Has there been any real world success with binary propellants (used in T2300, two inert liquids mixed in the firing chamber to produce the explosive)?

 

[Todg]

Originally posted by Straybow:
I've always thought caseless is a bad idea. It works fine if the rounds are contained in clips and protected from the elements.

Most people don't realize all the wonderul things cartridge cases do. As you note, they are very good at protecting the propellant from damage, mechanical, chemical, whatever.

They also extract a lot of heat from the chamber. With a caseless round, the heat generated by the propellant combustion goes into the generated gas or right into the chamber walls. in a cartrdge weapon, a good portion of the heat that would normally flow into the chamber is captued by the case instead, and then ejected. Caseless weapons run quite a bit 'hotter' than cased weapons.

The other big factor in cased ammunition is 'obturation'. When a gun is fired, the cartridge case expands and forms a gas tight seal with the breech so that gases can only escape out the barrel. In a caseles round, there is no case to 'obturate' and seal the breech. This means you have to resort to some kind of external obturator to seal the breeh. And unlike the cartridge case, which is basically used once, the external obturator has to function over and over agin, reliably for thousands of rounds. This is not easy to achieve, and makes caseless weapon much more difficult to make.

In fact, the advantages that caseless ammo offer are relatively small. Cased ammo works very very well. Any advantages of caseless ammo don't seem to justify the disadcvntages.

 

[Todg]

Originally posted by Sigg Oddra:
Has there been any real world success with binary propellants (used in T2300, two inert liquids mixed in the firing chamber to produce the explosive)?

Liquid propellants are being actively pursued for artillery. These include binary and even trinary component propellants. The system appears too complex for small arms, and doesn't offer any real advatages over more conventional systems in this platform.

For the serious geahead, I recommend "Liquid Propellant Gun Technology" by Kilingenberg, Knapton, Morrison and Wren. Aside from LP guns, hybrids and ETC guns are coveren in detail. Be warned, this book is designed for serious students of the technology, and is very technical. It is also very expensive (~$120). It's available from the American Institute of Aeronautics and Astronautics. See their website at http://www.aaia.org

 

[mike wightman]

Thanks for the reply and the link, but $120 is a bit steep. I think I'll give google a try first

 

[kaladorn]

Originally posted by Straybow:
I've always thought caseless is a bad idea. It works fine if the rounds are contained in clips and protected from the elements.

As someone who used to carry around a lot of ammo weight, reducing that would be nice. Dispensing with essentially valueless cases (and with, for the most part, a reduction in the amount of time a weapon has open parts as usually you'll not need a case ejection port open) and their weight seemed compelling to me and I still don't see an argument against it if the caseless round performs otherwise well.

As soon as you have loose rounds they get dirty, wet, chipped, etc. Now you've got fouling and misfire problems.

The trade off with the G-11 was the weapon itself was much better sealed, among other reasons because it didn't have to throw empty casing in normal operations. So in fact, reliability (I was led to believe) went up. And loose rounds? We don't even carry those for C7s.... we only ever carry full mags (well, 27-29 rounds since loading towards 30 seems to cause increase in feed issues).

With caseless you also have supply problems. Two manufacturers using their own powder formulas can have the same ballistics by controlling the amount of powder in the shell. For caseless I guess the powder part could be hollow to allow for variable sized charges with different powders. That would require more engineering and testing than regular ammo charge design.

If the powder is a standardsized formula (not 'up to the manufacturer'), that just becomes part of the bulk ammo req. And the logistics problems may be lesser, as caseless ammo should pack more densely due to shape than conventional ammunition. And if it was your principal round type, you'd have it available... it wouldn't seem like an oddball ammo.

I agree with Corejob though, it didn't offer a huge advantage. But if some major adopter went with it for their next generation weapon, then it would be just because they were replacing a weapon due to age/wear, rather than due to the need for a brand new system that offers limited benefit.

What does 210 5.56mm casings and primers weigh? That's probably what the average grunt might save from caseless, all other things being equal.

 

[kaladorn]

Originally posted by Corejob:
Most people don't realize all the wonderul things cartridge cases do. As you note, they are very good at protecting the propellant from damage, mechanical, chemical, whatever.

So does a good mag.

They also extract a lot of heat from the chamber. With a caseless round, the heat generated by the propellant combustion goes into the generated gas or right into the chamber walls. in a cartrdge weapon, a good portion of the heat that would normally flow into the chamber is captued by the case instead, and then ejected. Caseless weapons run quite a bit 'hotter' than cased weapons.

True, but we've come a long way in cooling/materials/thermodyanmic sciences lately. This might well be easily manageable using current capabilities.

The other big factor in cased ammunition is 'obturation'. When a gun is fired, the cartridge case expands and forms a gas tight seal with the breech so that gases can only escape out the barrel. In a caseles round, there is no case to 'obturate' and seal the breech. This means you have to resort to some kind of external obturator to seal the breeh.

A valid point. But do you know how they accomplish this with the rotating breech of the G-11? (an interesting idea, too).

And unlike the cartridge case, which is basically used once, the external obturator has to function over and over agin, reliably for thousands of rounds. This is not easy to achieve, and makes caseless weapon much more difficult to make.

Perhaps for now. There comes a point in materials and industrial advancement this will likely be a trivial excercise.

In fact, the advantages that caseless ammo offer are relatively small. Cased ammo works very very well. Any advantages of caseless ammo don't seem to justify the disadvantages.

Guess it depends how much of it you carry. I used to carry between 140-200 rounds of 7.62 x 51 jacketed NATO ammo for my rifle, and quite often another couple of hundred of belted 7.62 for the SAW. That's a measurable weight of casing... and if one could have done away with it, that'd be all to the good, all other things being equal.

And again, in a sci-fi environment, there isn't really any good justification for it not being... unless you want there to be.

 

[Todg]

M855 ball ammunition (5.56x45mm) masses 12g. The HL G11 4.7mm caseless cartridge masses 7g. It should be noted that the M855 has a 4 bullet at 921 m/s for about 1670J vs the 4.7mm with a 3.4g bullet at 930 m/s for a muzzle energy of 1460J.

The caseless round does show a significant weight savings, although anyone who worried that the 5.56 is too small will find the G11's round microscopic.

I had a chance to handle the ACR version of the G11. Human engineering is certainly not HK better areas. The weapon feels like a 9 lbs 2x4. It's big and clunky.As a first iteration, it wasn't bad I suppose.

My understanding is that obturation is still a problem. The weapon vents propellant gases into the interior. Still, it is probably no worse than the M-16. Despite the venting, the weapon apears to continue functioning.

I agree that assuming all the problem with caseless ammo are worked out, it does make sense if you are already planning on replacing your rifle. You are however, limited to certain projectile types that lend them selves to encapsulation. At the very least, flechettes don't appear to be an option with the HK design.

I should still have some photos of the various ACRs, including the G11. I'll ook for them and post them on one of my web sites. My personal favorite in terms of ergonomics was the Steyr ACR. More data on the G11 is available at http://www.hkpro.com/g11.htm including comparisons with other weapons.