TWMSR

Frame/spacer.

Indeed. But if you look at pictures of Turkish "60s" you can see that it is not uncommon to put spare track links or wheel discs on turret walls. Those parts could be blown off when hit by warhead. In this case there coul be seen splash marks on yellow paint on the left.

Hard to tell. L28 used WC core with WHA cap/nose and steel cup in-between. The cup would not be seen without disassembly, but core and cap material should differ in look. At this picture  WC cores of older APDS looks darker than supposed WHA cores of newer APDS. Probably L52, not L28.

Copying is the highest form of flattery!

90 mm M36/M41, L/50, HEAT-T M431 (5,8 kg), mv =1219 m/s

90 mm JPz BK, L/40,5, unknown shell type (5,74 kg), mv=1181 m/s

It could be expected in case of AP-T M318 (11 kg) mv would be circa 800/m/s when fired from 90 mm JPz BK.

On 3/22/2020 at 7:04 PM, J.J.S. said:

This lower part is quite heavy and will move with lower velocity than upper plates. Moreover these mounting beams will additionally slow it down. That's why such movement shouldn't be efficient against cumulative jet.

The last statement does not stand for itself. Firstly, AFAIK term "shouldn`t be" is not used commonly in research papers on shaped charge vs ERA. Secondly, ERA bricks of ERAWA family already proved to work vs cumulative jet, and it`s efficiency was not a matter of doubts.

From what is known about ERA-jet interactions, rear flyer plate (that one that is chasing the jet) is more important than forward flyer plate. It is good when rear flyer plate is thick, because that means more material get into jet trajectory. It is good when ERA is sloped at last 60 degrees, because it gives more efficient use of movement of flyer plates. In case of ERAWA those conditions are met, to some degree. Another very important condition is velocity of back flyer plate - should be as high as possible, to extend the time of interactions with jet. ERAWA's rear flyer plate is probably slower than forward. But is was already said that ERAWA-2 was still quite good vs some tandem warheads. It is not big surprise that '80s/'90s development is not good enough vs more modern and more potent shaped charges.

That 3-T precursor liner is circa 140-145 degree cone. SCs with so wide angle cones lay in transition area between EFPs and classic jets.

WH 98 seems to be triple warhead. The second charge is smaller, because the jet must fit into cavity made in armour array by the first charge. If the second one is of greater diameter, there is  probability, that jet would hit outside crater digged by smaller precursor  and it`s distruptive power would be wasted.

Wiedzmin, in case of ERAWA-1 both upper and lower metal parts of case are flyer plates. Mounting beams are not sturdy enough to stop lower part (base) of case movement and are being smashed in the process. So, even if only upper part looks like flyer plate, both are flyer plates. And in ERAWA-2 there is one more plate between H.E. layers.

3 hours ago, TokyoMorose said:

 

What is *doubly* weird is that the Chinese gun internals are hard-chromed. The 2A46 family did not introduce that until the 2A46M - so the Chinese made the effort to modify production tooling and procedures to allow a good chroming, but didn't also copy the rather simple front-change screw mechanism that is very well known? Really is a baffling combination of gun "features".

Because it is copy of 2A46 gun, not 2A46M. Design is old, with single recoil buffer, short cradle, no fast barrel change feature. But materials, some details, finishing touches could be sinicized. One example is barrel, made with more modern technology than orginal, another one are gun trunnions, that fit in vintage, T-54-style frame mounting, not T-62+ sockets integral to turret front casting. It is a bit of steampunk in it, mix of old and new developments.

alanch90,

note that "only 100 m/s" lower velocity means about 1800 meters difference in anti-armour performance between faster and slower projectiles versus same, specified target.

Militarysta,

there is general agreement on obsolescence of RHA equivalent as a way to define projectile performance, from many various reasons. On the other hand there is nothing better we have. Commonly accepted standard, namely NATO targets, are even more archaic, since those arrays today can be pierced probably from 20+ kms. RHA equivalent remains a bit more useful,  because it gives some numbers that could be compared with other numbers, of another ammunition types. It is also easier to imagine penetrating power in millimeters/inches than in km/miles. Last but not least, RHA equivalent is still used by producers of ammunition.

Let say it, that chart was made in Unterluss

Very sad.

Mk 3D with new TC sight? Artillery observation vehicle?

M829A3 uses stick propellant. M829A4 is said to use SCDB propellant (and KET, as an option), which AFAIK come in granular form.

And for sure it is mockup, a good one. It could be seen propellant containment bag, used in US 120 mm ammunition to prevent spillage. And new type of skive joint, near the bottom of combustible part of case.

Nice pictures, tank u!

Scav,

Hülsendeckel of DM 33 looks precisely like that on scheme, not like on pictures of mocked up JM33s.

Look closely at 105 mm DM 53 fins - those do not fit into those from scheme.

.

Scav,

Hülsendeckel, or consumable cone adaptor, must be and is a part of production rounds. You cannot assembly a round without it. It is a part that is being glued to cylidrical part of case after filling propellant. Yes, there are some novel ideas of partition of 120 mm cartridge, but DM 33 is not an example of that.

There are few patents that could be connected with 120 mm DM 33 project because of timeline and general similarity. That coloured diagram is from one of those - and it is just on, AFAIR, steel case around projo's tip. But there are few more, on making predetermined breaking points (present on DM 33 - check here), on changing tip properties via heat treatment, on fin section design etc. IMHO there is stron possibility that diagram posted by BkktMkkt's shows a projectile close or identical to DM 33.

As for your last notice, this could be an answer:

A surprising increase in the effectiveness when firing on multiply armored targets, especially on spring mounted armor plate, has been achieved by means of the proposed increase in the diameter in only one tip area, which has been proven through testing. Conservative estimates lead to the conclusion of an increase in effectiveness of more than 10% in connection with this improved kinetic energy projectile, compared with customary kinetic energy projectiles.

Yep, me bad, definitely not 3BM-22. Probably it is 3BM-26. 3BM-29 is said to use DU core. And at those graphics DU is coloured red-violet, not red

Left to right:

125 mm 3BM-15, 120 mm DM 13, 125 mm 3BM-22, 120 mm DM 23, 125 mm 3BM-32, 125 mm 3BM-42, 120 mm DM 33, 120 mm DM 53, 125 mm 3BM-59.

Re your question about supershot round: it is a part that gets discarded during shot, just like sabot. AFAIK it is there to prevent automatic guns from jamming, which could occur if pointy projectile nose is exposed.