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Zadlo

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Zadlo last won the day on October 24 2020

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  1. Well, almost 30% of spare parts for Polish Leopards 2A5 were made in the previous year in Poland. Excluding thermal cameras, machine guns and L44 cannons. Also we repair MB 873 engines at level 4 in Poland. And the agreement about licence production of Rheinmetall tank guns in Poland was signed today - currently only about L44 or even L44A1 but it looks like it may cover up future licence production of L55/L55A1 or even 130mm tank gun. Additionally WZM from Posen which repairs Polish Leopard 2A5 is currently building own welding shop so it looks like they can be ready to produce Leopards in Poland in agreement with KMW. Few years ago they even offered production of Leopard 2A7V in their factory.
  2. First at all military brass has to be involved into the procurement. But it's not obvious where there are two main commanders - one supported by MoD but with no power and authority among soldiers and second with power and authority among soldiers but not supported by MoD. And only one of them is responsible for this while the other one wasn't even asked for. Guess who is who.
  3. Comparison of armour steel based only on hardness is a bad comparison. There are five factors important for armour steel: 1. YS 2. UTS 3. elongation 4. impact strength 5. hardness Why hardness is on the 5th place? Because it is responsible only for penetrator's erosion and if the penetrator has tendency to mushrooming during initial penetration. But the second case is important in ceramics. Meanwhile the function of yield strength is to show how good energy is absorbed by steel. Tensile strength is indirectly related to hardness. Elongation is useful in NERA designs (exactly in bulging plate design) and when the plate is strong sloping in order to richochet the penetrator. And impact strength is a test which shows the absorption of energy by tested material. In all of armour standards there are always two verified factors - hardness and impact strength. You've said that DEF STAN 95-25 cast steel and 4" thick MIL-DTL-12560 wrought steel offers the similar protection due to similar hardness. But it's not true. British cast steel requires absorption of at least 40 J during Charpy test. Standard doesn't define the temperature of samples so the conclusion is samples are tested in room temperature. Meanwhile 4" thick American wrought steel requires absorption of 55 (when steel has 300 HB) to 82 J (when steel has 250 HB) during Charpy test and at the same time samples must be cooled to -40 degrees. So in the effect American wrought steel protects a lot better than British cast steel because the first one absorbs the energy better than the second. There are two better comparisons for DEF STAN 95-25 cast steel. The first one is MIL-A-11356 cast steel which at 60mm of thickness (the same as CR2 turret base thickness) has hardness between 255 and 293 HB and required minimum impact strength between 35 J (for 293 HB cast) and 51 J (for 255 HB cast). That's comparable values. The second one is civilian grade 'armour' steel called S690QL (made according to EN 10025-6 standard) which has YS >690, UTS 770 - 940, elongation >14% and Charpy impact strength 50 J at 0 degree Celsius or 30 J at -40 degrees. And even though that's a civilian structural steel it will perform better than British cast steel.
  4. DEF STAN 95-26 is based on RARDE 823. Both have the same mechanical requirements, chemical composition and tempering method. Also 95-26 links directly to 823.
  5. Last layer (especially thick one) is influential for protection of whole package - in this case placed in front of this cast. Using well made RHA, well made CHA or badly made CHA (not only package) determines if the penetrator or jet even reach the last layer. These few per cents of difference which are important for tankers' lifes. In another case it would prove that armour blocks aren't even attached to the turret but they levitate in the air.
  6. Meanwhile cast steel used in Challenger 2 (made according to DEFSTAN 95-25) is a lower quality than the one used in Stillbrew Chieftain and possibly Challenger 1 too (made according to RARDE 823 aka DEFSTAN 95-26).
  7. That's the same problem as with Iron Vision.
  8. MIL-A-46099C limits the thickness of DHS to 14mm, meanwhile MIL-DTL-32332A limits it to 16mm.
  9. Zadlo

    Discord

    First at all - How to get into SH's Discord server?
  10. The newer is the deep modernization of the older one.
  11. This scheme is similar to BDD structure but with thicker steel plates. This type of structure greatly improves protection against kinetic rounds only when rod fractures during the penetration. It is possible when you use carbide cored ammunition instead of heavy alloy ones. .
  12. If composite armour with glass textolite filler can be named NERA Basically these drawings are too old to contain NERA in it.
  13. You behave like Australia doesn't have any ammunition plant and they won't have. Meanwhile RWM is building own facility in Maryborough and there's no problem to produce 30x173mm ammunition for both Boxer and Lynx.
  14. How many ACV 1.1. uses MCT-30 turret? Is it 0?
  15. You have a bit bigger issue because you already use Bushmaster II. It depends on Rheinmetall if you'll use different links for MK 30-2 and Mk 44 or Lynx will be armed with WOTAN 30 which can use Mk 44 links. But for Australians it's not an issue. Tbh they choose the first 30mm autocannon and no matter if they choose Bushmaster II, MK 30-2 or WOTAN 30 they'll not solve this problem because Americans use Bushmaster II only on Stryker Dragoon (81 pieces) meanwhile XM319 uses linkless 30mm ammunition.
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