Secondary Armament on MBTs

[Waylander]

Huh?
Do I get it right and you want to combine a tank turret and the turret of a self propelled howitzer in one chassis?
That's not going to be big monstrous.
And what would you gain from it?
What makes the MBT an effective weapon system is it's combination of firepower, protection and MOBILITY.
Such a vehicle would be big (easier to hit), less armored and slower.

I also don't even remotely understand why you want to combine a MBT and a SPH in one chassis.
Both have very different missions and can only fullfill them if they are seperated. Or how do you give fire support with the howitzer while you are engaged in mechanized combat?

Where do you get these ideas from?

 

[Firn]

Where do you get these ideas from?

Perhaps by reading in my little thread where I point out that a MMBT (Main Mortar Battle Tank) might be an useful fire support asset for armored and mechanized formations

One should also keep in mind that during the Korean war (IRRC) and the Soviet campaign in Afghanistan MBTs were used in the indirect fire role, sometimes shooting from specially prepared ramparts. But of course Waylander is overall quite right.

 

[Waylander]

There is a "little" difference between an AMOS like self propelled mortar on a MBT/IFV chassis and a 120 ton beast with the turret of a Leopard II and a PzH2000.

The Sovjets also emphasized the direct fire support role of artillery. Their doctrine at least included the iea of self propelled artillery giving direct fire support during some situations while the west usually refers to direct fire as a mere way of self protection even though it might happen.

IIRC a battery of M109s destroyed a couple of Iraqi AFVs with direct fire during OIF when they accidently stumbled upon them en route to a new firing position.

Note that I really like the concept of modern self propelled mortars and IMO only the price tag keeps them from a wider instruction in several armies.

 

[Firn]

IIRC the Israelis started to greatly enhance the training time for rapid direct fire against moving and static targets after the Yon Kippur war, where the Syrian assault swept also over part of their in-duty M109. It seems to have payed of in the 82' Lebanon campaign, but of course the situation was a bit different. I posted the article somewhere here...

It seems that the Soviet way was both a result from lessons learned in WWII and a cumbersome but highly efficient way of organizing artillery support. The organic and responsive direct fire mitigated (or should have) the downsides of their system of the indirect fire support.

Personally I think doctrine is very right to state that self-propelled howitzer should usually operate 10-15km behind the frontline, but as war is chaotic one can never know what might happen. But there is no place for a PzH Leopard II.

 

[tatra]

Hi,

Just curious on people's thoughts regarding secondary armament on MBTs.

As a former US Army tank crewman (and gunner) I would have loved to have a heavier caliber coaxial MG than the 7.62mm M240. Something that would have allowed me to make better use of the tank's sights and FCS for long range shooting, and would have had the ability to defeat light armor and soft skin vehicles as well.

IMHO a co-axial .50cal would be ideal - either a Browning M3 (M2 with higher ROF) or a GAU-19/A GECAL 50. The .50cal SLAP-T round can defeat 34mm of armor at 500m which would make the weapon useful against light armored vehicles - no need to waste a 120mm main gun round. A .50cal coax with a high rate of fire would also be very useful in dealing with built up terrain - a GAU-19/A spitting out 2000 rpm could demolish most hard cover in short order. Plus the psychological effects of such a weapon would be substantial. As I understand it when the XM1 was being developed, one of the proposals for secondary armament (advanced by US Army tank crewman with combat experience in Vietnam) was TWO M2 .50 cal machineguns - one on either side of the main gun, which would fire simultaneously. Later it was changed to mounting a the Bushmaster M242 25mm chaingun on one side of the maingun, and the M240C 7.62mm MG on the other. This was deleted becuase of cost.

I'd also like to see the commanders M2 .50cal replaced by a remote (like on the M1A2 TUSK) weapon station with either a 40mm AGL with airburst capability or the new 25mm OICWS. Having MGs for air defense on MBTs these days seems a bit anachronistic - I think having an AGL to be able to rapidly supress ATGM or RPG teams would be better.

Any thoughts?

Adrian

I'ld like to see a coaxial cannon. Original Britich Centurion has a coaxial 20mm Polsten cannonSwiss Pz61 and early Pz68 had a coaxial 20mm cannon, as did French AMX-30, AMX-32 and AMX-40. Leopard 2 prototype 11 had a remote controlled 20mm cannon on the turret roof. Czech firm offers a T-72 modernization package (Moderna), including either two Oerlikon Contraves 20 mm KAA-001 cannon mounted externally one either side of the turret or a 30 mm 2A42' cannon on right side of turret only.

On the turret roof perhaps something like a 30mm ASP instead of a Browning .50? And what about the 60mm mortar adopted by Israelis for Merkava and M-60 upgrades? That can have many use, from suppression to illumination to smokelaying.

 

[kato]

Leopard 2 prototype 11 had a remote controlled 20mm cannon on the turret roof.

It was turret 11, not prototype 11. And the system was so cumbersome and problematic that it didn't make it into any of the other 20 prototype turrets. Turret 14 was the first one implementing lessons from the Yom Kippur war btw. All 16 pre-AV prototype turrets also fielded a crew-operated single-shot grenade launcher similar to the 60mm mortar on the Merkava that didn't make it into the final model as well (wasn't mounted on the AV turrets 18-21).

30mm ASP? Why would you want to use a cannon whose HE performance is pretty much the same as a 40mm Mk19, and shows at best equal penetration performance against cover as a .50 HMG ... except at twice the weight and size of either, well over twice the recoil forces, and a bit over half the cadence of even the AGL? And that's apart from the fact that ASP itself is dead - they're trying to revive it as M230-LF now...

 

[eckherl]

It is official,

M1A2SEP will be getting CROWS 2 as a future upgrade, 50 cal will stay with system. General Dynamics is responsible for this project and there is a good chance that this system will also be mounted on Saudi M1A2s.

 

[Waylander]

I am not sure that I understand this.
Does the M1A2SEP gets CROWS 2 while the TC's .50 cal remaisn on the turret, too?
Or do they remove the TC's .50cal completely while a .50cal is going to be carried by the CROWS 2?

 

[eckherl]

I am not sure that I understand this.
Does the M1A2SEP gets CROWS 2 while the TC's .50 cal remaisn on the turret, too?
Or do they remove the TC's .50cal completely while a .50cal is going to be carried by the CROWS 2?

Tank Commanders 50 cal will go bye bye. Two versions may be going thru testing, one with TC 50 cal replacement and another with two weapons systems, 50 cal and 7.62, the latter may be seen on a future block version when auto loader is installed.

 

[Waylander]

Thanks for the info.

 

[joeroot]

Huh?
Do I get it right and you want to combine a tank turret and the turret of a self propelled howitzer in one chassis?
That's not going to be big monstrous.
And what would you gain from it?
What makes the MBT an effective weapon system is it's combination of firepower, protection and MOBILITY.
Such a vehicle would be big (easier to hit), less armored and slower.

I also don't even remotely understand why you want to combine a MBT and a SPH in one chassis.
Both have very different missions and can only fullfill them if they are seperated. Or how do you give fire support with the howitzer while you are engaged in mechanized combat?

Where do you get these ideas from?

no i want to put a command vehicle with a crew of 6 put tracks on it and thicken the armore and mount a 7mm cannon on top for defence purposes or instead of the turret being a cannon but a mortat turret

 

[Firn]

Tank Commanders 50 cal will go bye bye. Two versions may be going thru testing, one with TC 50 cal replacement and another with two weapons systems, 50 cal and 7.62, the latter may be seen on a future block version when auto loader is installed.

I'm quite intrigued by the two weapon system, as I advocated it before. A small arm with lots of ammunition widens the options for the TC and should allow for more enduring suppressive fire. I wonder if a 40 mm GMG can be mounted instead of the .50 cal. It should complement it well when used on one part of the platoon's MBTs.

 

[Firn]

no i want to put a command vehicle with a crew of 6 put tracks on it and thicken the armore and mount a 7mm cannon on top for defence purposes or instead of the turret being a cannon but a mortat turret

Well the MBT has already tracks and thanks to the heavy armor it weights already 70+ tons. Switching the 120mm gun for a mortar won't lighten it much, as I guess that part of the turret must be adjusted to allow for the high elevation. A 70? mm cannon - if it exists - won't do any good as it won't be able to defeat MBTs and adds considerable bulk and trouble. For lesser vehicles direct HE/HEAT fire from a 120mm mortar should be threat enough.

A secundary armament like the Crow 2 with two weapon stations seems to me equally well suited for such a vehicle. The new Terrex APC of the army of Singapore has a very similar system.

 

[eckherl]

I'm quite intrigued by the two weapon system, as I advocated it before. A small arm with lots of ammunition widens the options for the TC and should allow for more enduring suppressive fire. I wonder a 40 GMG can be mounted instead of the .50 cal. It should complement it well when used on one part of the platoon's MBTs.

You may think that I am crazy for stating this, but if and when we decide to go the robotics route then I can see this as being a possibility.

 

[tatra]

It was turret 11, not prototype 11.

So what. Totally irrelevant.

And the system was so cumbersome and problematic that it didn't make it into any of the other 20 prototype turrets.

Did I suggest to use that particular implementation? I think the point is more what are possible locations for heavier secundary armaments.

Turret 14 was the first one implementing lessons from the Yom Kippur war btw. All 16 pre-AV prototype turrets also fielded a crew-operated single-shot grenade launcher similar to the 60mm mortar on the Merkava that didn't make it into the final model as well (wasn't mounted on the AV turrets 18-21).

Of course, this was before the advent of the Merkava and it demonstrating in combat the usefullness of the 60mm turret mortar.

30mm ASP? Why would you want to use a cannon whose HE performance is pretty much the same as a 40mm Mk19, and shows at best equal penetration performance against cover as a .50 HMG ... except at twice the weight and size of either, well over twice the recoil forces, and a bit over half the cadence of even the AGL? And that's apart from the fact that ASP itself is dead - they're trying to revive it as M230-LF now...

Oh, I don't know, just for the heck of it? Maybe because of the very combination of characteristics your mention Meanwhile, if it is so dead, how come it is being attempted to revive it? Incidentally, how correct is that statement?

"Development of the 30 mm M230LF (Linked Feed) cannon began in October 1994. It is a derivative of the M230 Chain Gun usually encountered on AH-64 Apache ... There are two versions of the M230LF. Both feature a longer barrel than the original M230 (152 cm, rather than 107 cm), with a higher muzzle velocity (838 m/s rather than 800 m/s). The LF-1 is intended for use in heavy applications, such as armament for an Infantry Combat Vehicle (ICV). The LF-2 has hydraulic recoil dampers which, together with a longer recoil stroke, cut the peak recoil load from 1,360 kg to 750 kg to enable it to be fitted to light vehicles and small boats."
ATK M230LF 30 mm cannon (United States) - Jane's Infantry Weapons

The ASP-30 with M789 hepd ammo penetrates light armor (50-60mm armor steel, e.g. BMP 1/2) out to 4km and has far greater effects than .50.

 

[kato]

50-60mm RHA is the exact same performance as a 40x53 HEDP grenade - of course, since both contain virtually the same amount of explosives.

4 km out of a 838m/s projectile? Ballistic trajectory, sure. I can claim that a PzF3 has a range of 3.5 km too

 

[tatra]

50-60mm RHA is the exact same performance as a 40x53 HEDP grenade - of course, since both contain virtually the same amount of explosives.

4 km out of a 838m/s projectile? Ballistic trajectory, sure. I can claim that a PzF3 has a range of 3.5 km too

You said "a cannon whose HE performance is pretty much the same as a 40mm Mk19, and shows at best equal penetration performance against cover as a .50 HMG "

Lets - for the sake of argument - assume range is just 2.2km. Then the 30mm round still punches much harder than ma deuce i.e. a bigger hole and behind armor effect (you did see the images in that presentation, didn't you?).

While grenades fired from the Mk 19 AGL reach 2200 metres. In practical terms, however, this maximum range matters little for AGLs are usually tactically employed only up to about 1500 metres. Attempting to utilise the maximum possible ranges usually results in poor accuracy (or until recently at least) due to the still relatively low muzzle velocities involved. The case for high velocity, belt-fed grenades is 53 mm long (40 x 53 mm), containing more propellant and so producing a much higher muzzle velocity (from 240 to 242 m/s at the muzzle) to ensure the maximum range can be as much as 2200 metres.
Army Guide - Mk47 MOD 0 Striker40, Automatic grenade launcher

-----------[edit]----------
ASP-30

Application. A multi-purpose combat support weapon system, designed to replace the 12.7x99mm (.50 caliber) M2HB heavy machine gun and the 40mm Mark 19 automatic grenade launcher on ground tactical vehicles.

The ASP-30 fires NATO-standard 30x113mm ADEN/DEFA ammunition, in all types.

Rate of fire: 400-450 rounds per minute
Effective range: 2,000 meters

Firing the M789 High Explosive Dual Purpose ammunition, the ASP-30 can effectively deal with BMP threat-level targets out to 2,000 meters (2,187.2 yards).

http://www.forecastinternational.com/Archive/or/vo0014.htm

.50" Browning, GAU-19/A, Barrett .5" etc
12.7 x 99 mm cartridge
20.3mm rim
API / 43 gram projectile
890 m/s velocity

Modern high-velocity automatic grenade
40 x 53SR mm cartridge
43.6mm rim
HE / 245 gram projectile
240 m/s velocity

Aden Mk 4, DEFA 30M550, M230 a/c
30 x 113B mm cartridge
33.3mm rim
HE / 270 gram projectile
800+ m/s velocity

http://www.quarry.nildram.co.uk/ammotables.htm

 

[Marc 1]

no i want to put a command vehicle with a crew of 6 put tracks on it and thicken the armore and mount a 7mm cannon on top for defence purposes or instead of the turret being a cannon but a mortat turret

Why? If it's a command vehicle, then surely it would have all the necessary gear to order an artillery bombardment if need be from a regiment/battery/section or platoon of guns/mortars/air support. If we are talking a true command vehicle for say a Brigadier, why would it need a 70mm gun for self protection? Surely it should be far enough forward to ensure the boss can be in control of the battle, without being INVOLVED in the battle. That's not a Brigadier's job.
There is a reason this mythical beast doesn't exist - it's not required.

 

[joeroot]

Why? If it's a command vehicle, then surely it would have all the necessary gear to order an artillery bombardment if need be from a regiment/battery/section or platoon of guns/mortars/air support. If we are talking a true command vehicle for say a Brigadier, why would it need a 70mm gun for self protection? Surely it should be far enough forward to ensure the boss can be in control of the battle, without being INVOLVED in the battle. That's not a Brigadier's job.
There is a reason this mythical beast doesn't exist - it's not required.

well it wasnt for a command vehicle but they made somthing similar to what i was talking about
the new warthog that the british have is true a transport vehicle but at the same time if you take some of the inside out and lengthen both the tracks and the body of the vehicle and put command tactical gear in it then it is almost but not quite what i was talking about

 

[Waylander]

Huh?
A Warthog is not even remotely comparable to what you described.

You talked about an enlarged MBT chassis with a 6 men crew and direct fire weapons as well as artillery capabilities.

A warthog on the other hand is a lightly armed and armored, tracked vehicle for heavy and difficult terrain.

That's as far away from each other as it gets...