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    Armor measurement standards convertion formula

    The-thing-next-door
    The-thing-next-door


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    Post  The-thing-next-door Fri Apr 26, 2019 1:59 pm

    Since Russian standards differ substantially from nato ones you cannot compare claimed protection/penetration stats directly, Though this has not stopped morons on the internet from doing it anyway.

    I have come across a few claims that Russian/Soviet methods of calculating armor penetration would be of higher standards than the ones used by foreign armies But I am not good when it comes to finding reliable sources so I need some help.

    Could anyone help me try and come up with a formula to help translate the an armor penetration value between standards?
    SeigSoloyvov
    SeigSoloyvov


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    Post  SeigSoloyvov Fri Apr 26, 2019 3:40 pm

    Well this "propagandist" will help.

    Keep in mind there is really no sure way to determine this stuff, the type of shell and other factors greatly affect the calculations, there is no set formula to determine this 100 percent.

    Armor measurement standards convertion formula Lamber11


    (T) Armor Plate Thickness (cm)
    (θ) Angle of Impact (radians)
    (D) Projectile Diameter (cm)
    (SEC)  (1 / cos[θ])  angle is measured in radians.


    Take that part then do this part.

    (VL) Limit Velocity (m/sec) for 50/50 penetration
    (α) Armor Constant (4,000 for RHA; 1,750 for 2.77 g/cc Aluminum).
    (L) Projectile Length (cm)
    (D) Projectile Diameter (cm)
    (Z) Z Factor (calculated previously)
    (M) Projectile Mass (grams)

    Armor measurement standards convertion formula Lamber13
    The-thing-next-door
    The-thing-next-door


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    Post  The-thing-next-door Fri Apr 26, 2019 7:25 pm

    You cannot try to calculate a rounds penetration with such basic math that does not even take the material used to make the round into account.

    What I was suggesting is a formula to convert standard to standard wich while not accurate is a hell of alot better than comparing data gathered through difforent methods.

    You need to take the difforent protective properties of the RHA used in thests by difforent countries and then also the definition of penetration as some countries define that quite difforently,

    Your main factors will be the target material as there is no mythical "RHA" that always retains the same properties nomatter how you produce it, then there is the required percentage chance of penetration and the definition of penetration.

    A round with "800mm" penetration of low grade RHA with a chance of 50% to do so will not perform the same way as a round with "800mm" penetration of high grade RHA and a chance of 80% to do so.

    This is not the ideal way to compare rounds but uless you can get a bunch of the latest rounds and some guns to fire them into you garage it is probably the best option.
    SeigSoloyvov
    SeigSoloyvov


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    Post  SeigSoloyvov Fri Apr 26, 2019 7:47 pm

    The-thing-next-door wrote:You cannot try to calculate a rounds penetration with such basic math that does not even take the material used to make the round into account.

    What I was suggesting is a formula to convert standard to standard wich while not accurate is a hell of alot better than comparing data gathered through difforent methods.

    You need to take the difforent protective properties of the RHA used in thests by difforent countries and then also the definition of penetration as some countries define that quite difforently,

    Your main factors will be the target material as there is no mythical "RHA" that always retains the same properties nomatter how you produce it, then there is the required percentage chance of penetration and the definition of penetration.

    A round with "800mm" penetration of low grade RHA with a chance of 50% to do so will not perform the same way as a round with "800mm" penetration of high grade RHA and a chance of 80% to do so.

    This is not the ideal way to compare rounds but uless you can get a bunch of the latest rounds and some guns to fire them into you garage it is probably the best option.

    Then what you want really can't be calculated, this is what live fire tests are for.
    The-thing-next-door
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    Post  The-thing-next-door Fri Apr 26, 2019 8:36 pm

    You mean to say you cannot calculate the effects of percentage chances? Or compare resistance of difforent RHA's to various rounds to each other?

    This is not difficult the difficulty comes in finding out the details of the live fire tests used to calculate the penetration of rounds.

    When I have some spare time tomorrow I will get in touch with Putin and have him send over a T-14 Armata, some Vaccum 1 rounds an example of eavery nato tank currently in service. Then I will be able to say for sure if the round is effective or not.

    Probably not as it will likely break up before clearing out the turrets of the first few tanks. Adamantium rounds cannot come soon enough DU is simply too brittle and won't even kill a row of 5 tanks.

    Untill the a formula will do.
    SeigSoloyvov
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    Post  SeigSoloyvov Fri Apr 26, 2019 10:34 pm

    You cannot compare the different RHA'sno, sounds like you wanted to compare down to the structural level which simply no one online would have the data for that, a 152 round made in say China would yield different results fired from a German Gun just like it would get different numbers if fired from a russian gun.

    Just like Russian and German tank armor has a different "make up", that's why i said there is no 100 percent sure way to determine such a thing.

    You could at best adjust the armor constant in the formula to get a guesstimate.
    GarryB
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    Post  GarryB Sat Apr 27, 2019 4:00 am

    You are talking about penetration probability, which is a bit like calculating CEP, but to different standards.

    The formula is the same for everyone but the standards are different.

    For instance with CEP a 50% accuracy rating of 5m for a HATO round sounds impressive and the Soviet equivalent of 20m sounds terrible but they are actually the same because the HATO measure is 50% accuracy and the Soviet measure is four times higher at 95% accuracy.

    Very simply with a 50% probability the CEP of 5m means if you draw a circle around the point of aim 50% of rounds fired at that target will fall somewhere within your circle... that is the HATO standard.

    The Soviet standard is stricter because they demand a 95% probability of accuracy so the very same ammo on the same target the CEP would be four times bigger than the 50% level so four times 5m equals 20m... so if you draw a circle around the same point of aim that is 20m radius then 95% of all the rounds fired will be inside that circle somewhere.

    Same ammo, different standards of accuracy different figures for accuracy for a given range and weapon.

    Regarding ammo penetration performance instead of accuracy it was about penetration probability and is usually given as an R factor... in other words the armour penetrating 9x21mm ammo the new Russian pistols fire has an R100 of a x level body armour plate at 250m. In other words it will reliably penetrate that armour out to 250m and retain enough energy to penetrate a human body and inflict enough damage to kill the person wearing the armour.

    For a 9x18mm round the R100 might be zero metres, their might be no distance where it will reliably penetrate that armour all the time, though every 5th or 6th round might penetrate within 10m its R100 would be zero.

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