Scav

Armour dimensions of the M1A1 in the American Heritage museum (made by a friend):
Hull: 24" or 609.6mm to weldline, rumoured 4" plate behind that (101.6mm)
(Quoting friend)
Seems like there's some empty space there, or he could've missed something, but he agreed that LOS thickness was ~732mm.
 
Turret cheek loader: 29" or 736.6mm perpendicular
From front face to loader's hatch on outside: 78" (he had to hook the tape over, so -3" on the pic you see)  and from loader's hatch on inside to armour = 41", so turret cheek armour from front = 37" or 939.8mm.
 
Turret cheek gunner: 29" or 736.6mm perpendicular, less angled than loader's side, no measurement to commander's hatch and inside to get overal thickness but we assumed  same inner plate thickness.
(maybe the GPS wouldn't be able to fit if it was bigger?)
 
So, hull of M1 (1980) was same thickness and turret most likely the same too (732mm LOS), so how come they gave turret higher protection values than hull?
Seems a bit odd, CIA gave turret 400mm KE (on a turret variant, we don't know which) and 750mm CE, but hull generally gets values of 350mm KE and 750mm CE.....

In any case, reference threat for XM-1 (FSED I think) was XM579E1 (simulating 115mm APFSDS):
Penetration was estimated at 161mm @60° and 1470m/s (either PB or 500m ish).
UK estimated XM-1 at 320-340mm, which coincides with the 115mm at 800-1200m requirement:
As previously pointed out in this thread.
This doesn't talk about the XM-1s before the FSED it seems (why would they talk about an outdated design?).
 
So either CIA was talking about IPM1 turret ("long turret") or they somehow increased KE values for turret while keeping CE the same OR CIA was overestimating own armour?....
 
Anyway,  BRL-1 or early versions of Chobham don't seem to be very good against KE relatively speaking, NERA part itself seems to do very little for KE, simulated ammo (XM579E1) isn't the best against composite materials or complex targets.
Perhaps OG M1 only had ~350mm effective against KE on both hull and turret and IPM1 increased this to 400 or slightly higher, but I don't think that increasing the thickness of the turret with more NERA seems very efficient against KE.
IPM1/M1A1 probably have below 470mm against KE on turret (XM579E1), but maybe more against old slug type APFSDS and definitely less against 80s long rods.
 
This probably led to DU equipped M1s...... to compensate for relatively poor KE protection.

Armour dimensions of the M1A1 in the American Heritage museum (made by a friend):
Hull: 24" or 609.6mm to weldline, rumoured 4" plate behind that (101.6mm)
(Quoting friend)
Seems like there's some empty space there, or he could've missed something, but he agreed that LOS thickness was ~732mm.
 
Turret cheek loader: 29" or 736.6mm perpendicular
From front face to loader's hatch on outside: 78" (he had to hook the tape over, so -3" on the pic you see)  and from loader's hatch on inside to armour = 41", so turret cheek armour from front = 37" or 939.8mm.
 
Turret cheek gunner: 29" or 736.6mm perpendicular, less angled than loader's side, no measurement to commander's hatch and inside to get overal thickness but we assumed  same inner plate thickness.
(maybe the GPS wouldn't be able to fit if it was bigger?)
 
So, hull of M1 (1980) was same thickness and turret most likely the same too (732mm LOS), so how come they gave turret higher protection values than hull?
Seems a bit odd, CIA gave turret 400mm KE (on a turret variant, we don't know which) and 750mm CE, but hull generally gets values of 350mm KE and 750mm CE.....

In any case, reference threat for XM-1 (FSED I think) was XM579E1 (simulating 115mm APFSDS):
Penetration was estimated at 161mm @60° and 1470m/s (either PB or 500m ish).
UK estimated XM-1 at 320-340mm, which coincides with the 115mm at 800-1200m requirement:
As previously pointed out in this thread.
This doesn't talk about the XM-1s before the FSED it seems (why would they talk about an outdated design?).
 
So either CIA was talking about IPM1 turret ("long turret") or they somehow increased KE values for turret while keeping CE the same OR CIA was overestimating own armour?....
 
Anyway,  BRL-1 or early versions of Chobham don't seem to be very good against KE relatively speaking, NERA part itself seems to do very little for KE, simulated ammo (XM579E1) isn't the best against composite materials or complex targets.
Perhaps OG M1 only had ~350mm effective against KE on both hull and turret and IPM1 increased this to 400 or slightly higher, but I don't think that increasing the thickness of the turret with more NERA seems very efficient against KE.
IPM1/M1A1 probably have below 470mm against KE on turret (XM579E1), but maybe more against old slug type APFSDS and definitely less against 80s long rods.
 
This probably led to DU equipped M1s...... to compensate for relatively poor KE protection.

Interesting points:
Mantlet weighs 640kg
Barrel + breech weigh 1905kg but total assembly without mantlet is 3015kg, so 1110kg for cradle, recoil system, recoil guard, etc.
They tested APFSDS with L/Ds in excess of 30.
Sales brochure (?) from September 1982.

Interesting points:
Mantlet weighs 640kg
Barrel + breech weigh 1905kg but total assembly without mantlet is 3015kg, so 1110kg for cradle, recoil system, recoil guard, etc.
They tested APFSDS with L/Ds in excess of 30.
Sales brochure (?) from September 1982.

Interesting points:
Mantlet weighs 640kg
Barrel + breech weigh 1905kg but total assembly without mantlet is 3015kg, so 1110kg for cradle, recoil system, recoil guard, etc.
They tested APFSDS with L/Ds in excess of 30.
Sales brochure (?) from September 1982.

Interesting points:
Mantlet weighs 640kg
Barrel + breech weigh 1905kg but total assembly without mantlet is 3015kg, so 1110kg for cradle, recoil system, recoil guard, etc.
They tested APFSDS with L/Ds in excess of 30.
Sales brochure (?) from September 1982.

Well most description above are mistaken couse  most APFSDS-T above are not serial ones but R&D projects.
 
3BM29:
 

 
3BM26:


 
 
 
 
3BM42:


 

 
 
 

@Methos
Confirm that german special amrmour was not tested in USA:
https://babel.hathitrust.org/cgi/pt?id=msu.31293016483954;view=1up;seq=1
 
marevelous document about 105mm vs 120mm in USA:
https://babel.hathitrust.org/cgi/pt?id=uc1.31210024740399;view=1up;seq=1
"we know that 105mm is shit but it's cost effective"
 
BTW: Im agree that Leopard 2 is understimeted a lot. IMHO whole think is taken from T14 turret values or fact tahat in Leopard 2AV tehere was no special armour - just "cavity" made by frontplate and backplate - X-rayed by Americans who "discover" there is no special armour there. So propably (it's only my assumption) value for Leo2 is taken from XM1 whit thinner backplate and frontplate in leo-2 (2x 45mm RHA)
IMHO there is no other logical explanation of sucht value
 

Oh, sure. A former worker of Giat is certainly an unbiased and accurate source, a lot more trustworthy than the lying Swedes, who only wanted to buy the MBT best matching their requirements, instead of marketing a single tank type.
Sweden should have gone for the Leclerc, because that would allowed them to licence-produce the tank... it's not like they licence-produced the Leopard 2....
 
I am also sure that Sweden has absolutely no experience with hydropneumatic suspensions. I mean they only have been using a tank with hydropneumatic suspension since 1966, they surely lack the experience to judge when a hydropneumatic suspension is not suited for their terrain and is damaged by tests. But hey, some random former worker from the company knows better, he certainly isn't biased towards his own product. That never happens, just like people on the internet are never arguing in favor of certain AFVs, just because they are made in their home-countries...
 
The Leopard 2 won based on actual tests results, but this has to be due to corruption, because the Swedes should have chosen the Leclerc, a tank so unreliable that it wasn't considered ready for production by the FMV, instead? Because without corruption the Leopard 2 cannot win any competitions according to you. That the bribe in Greece was negotiated by Wegmann while Krauss-Maffei (responsible for the export of the Leopard 2) hasn't merged with it doesn't matter, I guess. But hey, Giat not only was caught manipulating tests during the Greek trials, but also got the sole export order thanks to bribing officials in the UAE (and officials in Germany to ensure the export of the EuroPowerPack to UAE is allowed). Certainly they are better people and make a better tank, just because they are French

I'm not sure about rainbows though Gotta dig deeper in the interwebz...

I might not be able to do that, but Rheinmetall just did that. During upgrade and rebuilding processes, turrets of Abrams and Leopard 2 MBTs have been completely stripped down, meaning all internal and external components have been removed. There is no reason why this should be impossible with the Challenger 2. The rest is a bit of engineering work that any medium-sized military vehicle integrator should be able to carry out. Technical documentation, specifications and blueprints were likely provided by the British military when the two Challenger 2 tanks were handed over to Rheinmetall (even if this didn't happen, they'd be able to do that by themselves).
 
During the early stage of the Leopard 2 development, three different construction mechanisms were used to create the turret shells for the prototypes. There really isn't any magic required to move from a cast to a welded construction.
 
As for the armor I can only point towards to Grant Turnbull's article, which mentioned this aspect: the Challenger 2 LEP is a program focused on obsolescence management. Replacing the gun or improving the armor protection isn't part of it and the figures released by Rheinmetall during its Capital Markets Day 2018 suggests that the company is banking on an increased budget for the gun replacement, so many changes to the armor aren't financially feasible. Most likely the statement from Turnbull's article is a reference to the changed in turret bustle protection and/or improved protection via using welded steel. A new armor package would require an extensive qualification program on side of the British MoD (risking delaying the whole program) and likely would have looked more similar to the other offers from Rheinmetall:

 
Why would the gun mantlet and original turret front shape remain unaltered, when the steel citadel is replaced and a whole new armor package is added?
 
 
I never said that. I posted a picture showcasing why it is not a brand new turret, you just added your own interpretations to it (at first "that guy considers everything obsolete that the guy marked" and now "that guy things everything is unaltered that is marked in the picture"). You notice that I never said anything along these lines; instead I even pointed out in my last reply, that the Thales Orion sight is now fitted. The identical location of the gunner's sight and commander's cupola, which leads to a weakspot is worth nothing, showing that this isn't exactly brand new. But well, maybe you should go for your own suggestions and play "wait and see", rather then registering to this forum because you were trigged by your own interpretations of my picture and made rash opinions.

T-80U and T-90 share FCS elements and ERA, what a wonder that they look similar. Tanks designed with the same technology mounting exactly the same components and featuring the same internal crew layout happen to look similar! The M1 Abrams uses different variants of the same turret design, again mounting the same components.
 
The Challenger 2's "brand new" turret keeps re-using the same (outdated) components, effectively not making it a brand new turret. It is a deep modification with new steel structure and some armor changes along the turret bustle.

"brand new welded turret"

So, did anyone else post pictures of the Marder 2 before?
My friends went to Koblenz and took these pictures:
 
They asked about the penetration of DM33, but apparently it's still being used by Japan so it's "classified"(surprisingly not other coutries).
Otherwise he'd be allowed to share it.

@SH_MM
So I finally managed to get my hands on the book Waffensysteme Leopard 1 und Leopard 2 by Spielberger thanks to a friend.
 
I found that he actually mentiones only skirt changes with the 8th batch but he words it in a way that makes it look like new integrated armour:

"Schürzenpanzerung" looks and sounds a lot like "Schützenpanzerung" (if that's even a word), perhaps some authors misread this and used it themselves?
 
In any case, he does specifically mention that only the skirts changed (interestingly, both the heavy and light ones).
 
For the 6th batch he does specifically mention new base armour though:
 

So, did anyone else post pictures of the Marder 2 before?
My friends went to Koblenz and took these pictures:
 
They asked about the penetration of DM33, but apparently it's still being used by Japan so it's "classified"(surprisingly not other coutries).
Otherwise he'd be allowed to share it.

So, apparently the Swedes tested the Rheinmetall smoothbore 105:
https://fromtheswedisharchives.wordpress.com/2019/01/03/rheinmetall-105-cm-smoothbore-performance/
 
Quite interesting, I wonder how well it lines up with this:
I read on this forum that the picture above was user made from real data, anyone know more?

http://www.dtic.mil/dtic/tr/fulltext/u2/a554529.pdf
A fairly exhaustive look at the work of Prof. Dr. Manfred Held (PBUH), and the science of reactive armor initiation.

So, did anyone else post pictures of the Marder 2 before?
My friends went to Koblenz and took these pictures:
 
They asked about the penetration of DM33, but apparently it's still being used by Japan so it's "classified"(surprisingly not other coutries).
Otherwise he'd be allowed to share it.

So, did anyone else post pictures of the Marder 2 before?
My friends went to Koblenz and took these pictures:
 
They asked about the penetration of DM33, but apparently it's still being used by Japan so it's "classified"(surprisingly not other coutries).
Otherwise he'd be allowed to share it.

So, did anyone else post pictures of the Marder 2 before?
My friends went to Koblenz and took these pictures:
 
They asked about the penetration of DM33, but apparently it's still being used by Japan so it's "classified"(surprisingly not other coutries).
Otherwise he'd be allowed to share it.

So, did anyone else post pictures of the Marder 2 before?
My friends went to Koblenz and took these pictures:
 
They asked about the penetration of DM33, but apparently it's still being used by Japan so it's "classified"(surprisingly not other coutries).
Otherwise he'd be allowed to share it.

So, did anyone else post pictures of the Marder 2 before?
My friends went to Koblenz and took these pictures:
 
They asked about the penetration of DM33, but apparently it's still being used by Japan so it's "classified"(surprisingly not other coutries).
Otherwise he'd be allowed to share it.

So, apparently the Swedes tested the Rheinmetall smoothbore 105:
https://fromtheswedisharchives.wordpress.com/2019/01/03/rheinmetall-105-cm-smoothbore-performance/
 
Quite interesting, I wonder how well it lines up with this:
I read on this forum that the picture above was user made from real data, anyone know more?