Sheffield

Got another question for all of you;

Is anyone is possesion of this but in a bigger format/better resolution?

Hi, wanted to ask if anyone has got any details on weight distribution of the Leopard 2A4; i.e how much turret shell/empty turret, hull shell/empty hull and if possible composite armour weight.

Thanks.

From this article, it appears that the Army had little to no say in this and that it was wholly orchestrated by the PiS party leader Jarosław Kaczyński, even the Prime Minister is opposed to it, so, the deal appears to be entirely political.

https://wiadomosci.gazeta.pl/wiadomosci/7,114884,27334615,abramsy.html#s=BoxOpMT

On 4/20/2021 at 7:13 AM, Atokara said:

So I've seen this image used a whole lot across the internet as an estimate for the proportions of DM53 and I thought I would do my own measurements on it to see how things line up.

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Disclaimer: I am merely providing my own interpretation of the measurements using the same methodology as whoever originally posted the image. Pixel measuring is an inherently inaccurate measurement tool and very subjective especially on blurry images such as this as people will have different opinions on which pixels can be considered part of the rod and which cannot. I accounted for pixel bleed as best I could by ignoring the softer and less consistent outlines where it was applicable. I do not consider my measurements any more correct and encourage other people to do their own measurements to compare to as well. In the image M829A3 and DM53 are not scaled exactly the same, there is a few px difference, so the ratios for both OP and my measurements will vary between the rounds.

 

Both DM53 and M829A3 don't have any officially published lengths, so people have gone to pixel measuring as a way to get estimates.

 

I started with M829A3 first by taking the pixel ratio for OPs estimate of 930mm. At 696px long this gave a ratio of 1.3362. The sabot diameter is always 119.9mm which makes it an excellent scaling tool which is what I used for my measurements(here I rounded it up to an even 120mm for simplicity sake). At 90px wide the ratio I got was 1.333 repeating. At a 0.003 difference OP did a good job measuring 829A3 imo as my ratio gave me a total length of the projectile of 928mm, only a 2mm or less than 2 pixel difference in our measurements. For all intents and purposes I consider M829A3's measurements accurate as can be estimated using this method.

 

Now onto DM53. Using OPs estimate of 760mm that gives us a ratio of 1.381818. Going off of the sabot which is 88px wide, I get a ratio of 1.3636 repeating. Now the difference here is a bit bigger (10mm or just over 7 pixels difference which I consider far outside the margin of error of 1-2pixels from M829A3) and when applying my ratio to the 550px long rod I get to total length of exactly 750mm. I actually found that OPs measurements for the diameter of DM53 lined up pretty well with mine just being a 1mm difference, but that is understandable due to the smaller pixel count of the diameter.

 

My last issue is with how OP measured the depth that the actual penetrating rod goes into the fin section. The pic of M829A3 is a proper cross section and we can see exactly where the rod ends so there is no estimates there, however the DM53 pic isn't a cross section and OP has given his own estimate of where he thinks it might end. To find a more accurate (but not exact) estimate in the ball park of where it might end I utilized the ratio of fin length to depth that the rod goes into that section. Here I also brought in a diagram of Type 10 APFSDS and I will explain why later.

 

M829A3 has 125mm long fins based on my measurements, 28mm or 22% of that length is overlapped by the penetrating rod.

DM53 has 110mm long fins based on my measurement and OPs estimate puts his estimate of where the rod might end at a depth of 54mm or just shy of 50%

 

Here I brought in a diagram of Type 10 APFSDS, because despite how secretive the Japanese are about their military equipment, we know quite a bit on this round. I used it as a control value to compare my estimates of M829A3 and DM53.

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At 748mm long for the projectile and 350 pixels across I got a ratio of 2.13714. With the sabot at 56 pixels in diameter applying my ratio gives 119.6mm which is well within the margin of error (which is expected as we already know the measurements).

 

Now that we know the Type 10 diagram is accurate we can go back to the fins. Type 10 has 117mm long fins and a 32mm rod depth into the fin section which gives a 27% overlap (M829A3: 22%, OP's estimate DM53: 50%). And that is where my issue lies. I went ahead and gave DM53 the same overlap as Type 10 at 27% as M829A3 has a very different and longer fin design that pushes farther past the projectile body. 27% of 110mm gives 30mm and when measuring to the penetrator tip that OP estimated we get a 625mm penetrator length and an overall projectile length of 750mm for DM53.

 

Let me know if I screwed up anywhere.

Don't hold me on this but as far as I know, there was a picture of a brochure of DM53 posted sometime in the past on the net where it said the penetrator body was 685mm though I don't remember if it also said anything about the diameter;

Regardless of this, i think comparing DM53 to Type 10 AFPSDS is a bit of a moot point and it would do us better to compare DM53 to M829A1/2 which both have 680x22mm and 690x22mm penetrators respectively in a projectile body roughly ~760mm long (though it's 779mm long in total).

There's also the case of yet another, I believe Rheinmetall brochure from 2014 or so stating that the projectile body of DM53 is 745mm long (i'm assuming that they excluded the fins that extend beyond the body of the main body of the projectile.

I've done my own share of estimates on DM53 and 63 in my free time and this is what I had got:

DM53:

DM63:

Did an estimate for DM53 once again just a moment ago;

In regards to the DM63 estimate, since i already had numbers for diamater and the stuff, i just did a comparison of how long fins on the 53 and 63 are, substracted the difference and that's how i got to ~770mm total length and 745mm "effective projectile length" (or perhaps it could be called in-flight length?).

edit: just found this, i don't know where this comes from but the penetrator length matches what was said in the Brochure, diameter is a bit too high though it also matches if you count in the ribs which in my estimates were roughly 25.8mm

And overall i think this graphic is legit; 

DM13 estimate:

DM23:

DM33:

They all roughly fit with penetrator length, diameter is a bit iffy cause I dunno what kind of criteria they used for diameter there.

I created my account only some time ago as I did not feel the need to really engage in discussions here but, I absolutely adore how our beloved friend Delete stated he was only "trolling" and about 2 posts later went back to being completely serious about everything he says.

This is pure gold, a flawless comedy, i'm on the verge of tears from reading and laughing at every piece of turd his mouth shits out and i'm sure there's more to come.