First M1A2 SEPv4 Abrams tank delivered to US Army Calvary Regiment

[LegionnairE]

With the gun on Abramsx demonstrator that could be introduce in future Abrams, most like it won't happen. Unless the U.S. Army combines both in terms of length, lighter gun and more powerful gun chamber on it. Depends on the threat of Russian and Chinese tanks. So far we haven't seen the need for it yet. Other countries especially in Europe are introducing the 130mm gun as well as more powerful 120mm L55A1 which has a gun chamber pressure to handle more powerful rounds being introduce. Those are mature tech and can be implemented on the Abrams. Just a reminder that a longer and more powerful chamber gun would require turret change and so on into the future Abrams.

New 120 mm gun and ammunition; a 20% performance increase in the coming years - EDR Magazine

While Rheinmetall’s new 120 mm smoothbore gun is already available and is in series production, the new APFSDS round has still to come.

www.edrmagazine.eu

While Rheinmetall’s new 120 mm smoothbore gun, known as L55A1, is already available and is in series production for Germany, Denmark and Hungary, fitted to the Leopard 2A7V MBT, the second element that will bring increased performances, the new APFSDS round, has still to come. As for the gun, Rheinmetall released the pressure differences between the L44 gun and the L55A1, which feature the same chamber volume that is of approximately 10 litres. The Extreme Service Condition Pressure (ESCP) is raised from 672 to 700 MPa, the Permissible Maximum Pressure (PMP) from 710 to 735 MPa, and the Design Pressure from 740 to 760 MPa. This pressure increase is vital to obtain the performances increases that the two rounds under development will bring with them.

The first one to enter service will be the DM73, which should reach qualification by year-end and will ensure an 8% performance increase over current DM53/DM63 rounds. However the round that will “squeeze” all the remaining growth potential from the 120 mm smoothbore weapon system will be the KE2020Neo; while the DM73 is an upgraded version of previous rounds, this one is a brand new development which qualification should start in 2024 to be completed by 2026, when it will become available on the market. The forecasted increase in performances should reach 20% compared to current armour piercing ammunition.

130mm L51 gun is out of the question, everybody who has seen it says that it can't be loaded by a human loader, shells are just too big. But 120mm L55 gun basically has the same breech, obviously this is the correct length for this gun.

Switch to the L55 gun between Leopard 2A5 and Leopard 2A6 was rather straightforward. Americans could have done the same thing. It's just remarkable that they still haven't done so.

I guess it's just that re-arming some 2500+ tanks would be too expensive to be considered.

 

[Oldman1]

130mm L51 gun is out of the question, everybody who has seen it says that it can't be loaded by a human loader, shells are just too big. But 120mm L55 gun basically has the same breech, obviously this is the correct length for this gun.

Switch to the L55 gun between Leopard 2A5 and Leopard 2A6 was rather straightforward. Americans could have done the same thing. It's just remarkable that they still haven't done so.

I guess it's just that re-arming some 2500+ tanks would be too expensive to be considered.

Not out of the question considering they factor autoloaders to handle such shells. Otherwise, why do it?

And yes they tested the L55 gun on the Abrams but there were some weight and stabilization issues hence I mentioned having to change the turret and so on. So they decided not to do it because of the cost to make such drastic changes among thousands of Abrams. Think it was around year 2000 they tested it. Right now they improve the ammo to handle any threats for now.

Also had to factor in the last 20 years was mostly fighting terrorists and guerilla warfare so the urgency for improving the tanks was not a priority except for improve armor protection. Who knows, with the war in Ukraine tanks probably being brought back to high priority, considering the Ukrainians will be using them so U.S. and others want data on its performance. Especially if they ever face the Armata or T90Ms.

Also the French still working on the 140mm gun.

 

[LegionnairE]

Not out of the question considering they factor autoloaders to handle such shells. Otherwise, why do it?

And yes they tested the L55 gun on the Abrams but there were some weight and stabilization issues hence I mentioned having to change the turret and so on. So they decided not to do it because of the cost to make such drastic changes among thousands of Abrams. Think it was around year 2000 they tested it. Right now they improve the ammo to handle any threats for now.

Also had to factor in the last 20 years was mostly fighting terrorists and guerilla warfare so the urgency for improving the tanks was not a priority except for improve armor protection. Who knows, with the war in Ukraine tanks probably being brought back to high priority, considering the Ukrainians will be using them so U.S. and others want data on its performance. Especially if they ever face the Armata or T90Ms.

Also the French still working on the 140mm gun.

How shitty your engineering must be that you have literally the heaviest tank in the world and it can't balance the weight difference between the L44 and L55 guns shameful.

Also I imagine that french 140 will go straight through an Abrams, bit of an overkill when Rheinmetall 130mm L51 does the job.

 

[Oldman1]

How shitty your engineering must be that you have literally the heaviest tank in the world and it can't balance the weight difference between the L44 and L55 guns shameful.

Also I imagine that french 140 will go straight through an Abrams, bit of an overkill when Rheinmetall 130mm L51 does the job.

Well the Abrams was design with 105mm originally before accommodating the 120mm and then a longer heavier gun. I'm sure the engineers could do it if they have the time and budget to make it work. Changing the turret or stabilization, etc. Think of the Leopard prototype of the 140mm gun and it has weight issues as well since it wasn't design for that unless they change the turret. 140mm gun has been around since the 1980s but still didn't get it to work.

This was U.S. Army Thumper with 140mm gun.


Fan art of what the tank could have looked like with the 140mm gun. See how much of a difference the turret looks compared to the M1a2 with 120mm gun?

 

[LegionnairE]

Fan art of what the tank could have looked like with the 140mm gun. See how much of a difference the turret looks compared to the M1a2 with 120mm gun?

I think the breech would hit the turret ceiling and gun depression would be abysmal on this one.

140 is very different because the breech is different. 120mm L55 has the same breech as the L44. I think it's inexcusable that they can't make the L55 work on Abrams.

 

[Oldman1]

I think the breech would hit the turret ceiling and gun depression would be abysmal on this one.

140 is very different because the breech is different. 120mm L55 has the same breech as the L44. I think it's inexcusable that they can't make the L55 work on Abrams.

Well the Thumper was just a testbed to make sure if the gun works. They introduce the CATTB that accommodates the gun hence you see the taller turret so the gun can handle the gun depression that it needs. Also had an autoloader.

 

[LegionnairE]

Well the Thumper was just a testbed to make sure if the gun works. They introduce the CATTB that accommodates the gun hence you see the taller turret so the gun can handle the gun depression that it needs. Also had an autoloader.

So why did this not move forward? Because there was no need back then I suppose.

Well, There's need for the L55 now

 

[Oldman1]

So why did this not move forward? Because there was no need back then I suppose.

Well, There's need for the L55 now

The end of the Cold War. I'm all for the L55 on the Abrams, even the new L55A1, but as you and I pointed out, its too heavy and would cost much to make massive changes to the turret and internals for that gun. Hence the other gun on the Abramsx demonstrator which is little bit longer but lighter. I'm more interested in its engine. Whats interesting was that there was suppose to be a turbine replacement with another turbine engine with almost 50 percent less parts and have fuel economy 25% more on the move and 50% while idle compared to the old turbine before APU was installed. That would have made the Abrams more fuel efficient and less need for a logistic tail.