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GH_Lieste

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Posts posted by GH_Lieste

  1. An alternative for shots from the map (rather than or instead of observed fires) is to set the bearing line line to 0 mils, and then give N-S (over-short) and E-W (right-left) corrections.

    An 'Incorrect' method, but can be useful when the observer is also dropping in and out of other vehicles and can find the relationships of each call made and their directions of fire can be forgotten over time - while if the user was only directing fires, this would be easier to manage.

  2. Technically both will orbit around a locus of points as the sun moves within the galaxy. Within the solar system 'fixed' coordinates the sun and each of it's satellites orbit around point between them, biased strongly toward the sun due to it's greater mass, but the sun is perturbed by the motion of all of the satellites it has orbiting it, no matter how insignificantly small...

  3. Ähhh, sorry, but the Tank Company in the independent Tank Bataillon in a Mot Rifle Regiment has a strength of 13 Tanks (1- 3x4)

    Nothing shown there indicates that isn't already done... this is indicating 3 companies of 3 platoons (this platoon strength not indicated).

    If not already accounted for then the platoons need replacing with the 4 tank equivalents to take the role of the MRR tank Bn.

    The Divisional TB is 5 (or sometimes 4?) companies of the 'normal' 10 tank company (3x 3 tank platoons).

    All the Tank Regiments use the 10 tank company formation as well.

  4. Use Excel:

    =(Normdist(0.5*tgtwidth, 0, .15*range(km),1)-Normdist(-0.5*tgtwidth, 0, .15*range(km),1))*(Normdist(0.5*tgthgt, 0, .15*range(km),1)-Normdist(-0.5*tgthgt, 0, .15*range(km),1))

    Range, Aim 'perfect', Half form error (shorter dimension)

    500m, .95, .50

    1000m, .65, .46

    1500m, .40, .33

    2000m, .26, .23

    2500m, .18, .17

    3000m, .13, .12

    With long range the assumption of perfect aim becomes less supportable, but it also becomes less critically important - with very tight groups an error of half target form will halve the accuracy, but with a highly dispersed group the reduction in accuracy will be far lower although the overall accuracy is lower:

  5. You always purchase the latest license version. With (historically) an occasional 'grace' period if purchasing immediately before a release cycle completes (or a temporary additional discount).

    If you had purchased 2.5x in early December, then you would need to update to 2.640, but purchasing now will get you 2.640, and the additional license was understood to be a secondary license for this later version.

  6. I think one lesson to take away is that even with the heaviest armour package in the world it is only intended to protect against some hits, not all possible damage.

    You should train and employ your vehicle as if he can damage you frontally, because even an M1A1(HA) can and will sometimes be penetrated from the front by any significant ammunition that strikes a weak zone (sight hood, cupola, driver's hatch area, turret ring, mantlet edge etc.)

    The tactics you use shouldn't really differ much between a Leopard 1A5 and an M1A1(HA) - you do gain a few additional options with the slightly better ammunition, and the heavier armour gives a higher probability of surviving any return fire you draw - but the systems are not all protected (suspension and tracks, gun-tube, sights etc are all outside the armour envelope, and stabilisation and electronics are vulnerable to non-penetrating shock damage) and the flanks of the heavy tank are not significantly better than those of the lighter vehicle and are vulnerable at all ranges to tank ammunition.

    Given the choice I'd operate in the heavier armoured vehicle, but it cannot be assumed that protection is equivalent to invulnerability.

  7. Without knowing anything better - looks like a unit coordination method - allowing left and right antenna (and therefore turret direction) to be observed, even if the vehicle is turret down (tall crops/dust)?

    This could allow the other vehicles to orient on the turret of the first vehicle to spot enemy without quite as much confusion as could exist.

  8. Your own movement (and therefore the muzzle) changes the muzzle velocity of the round (and therefore the flightpath).

    You must aim-off a varying amount depending on flight-time, and the angle and speed of motion (a maximum over the flank, and minimum fore-aft).

  9. According to the Odermatt system of equations and for the best ratio of energy/penetration, Steel needs very high velocities~ 2km/s, WHA really prefers high velocity ~1.65km/s , and DU is happier at mid velocities ~1.35km/s.

    While velocity drop can vary from one round to the other, the difference between material is more significant, except in cases of extraordinarily clean or draggy rounds - so BM32 should be the better long-range round if you can obtain an equal number of hits - ultimately accuracy and consistency is far more important than raw penetration.

  10. Most should be within 85-95% of muzzle at effective range - to all intents and purposes no significant variation with range.

    It is only important when the armour is only slightly below the penetration capability of the round - and shot placement is then far more important - the variation between protected and non-protected areas of the frontal array is usually 5-6 times this with-range variation of modern KE rounds.

    BM9 is capable of perforating the M1A1 from the front if it strikes a weaker area - even at 3km, while BM32 might fail against the protected front slope of the turret at the muzzle.

  11. Some more concrete information - though so far there is no EFC information, the character of wear is given in a Czech paper for BM-15, OF-19, TAPNA (modern-ish alloy sabot design).

    The OF-19 is almost entirely eroding the breech end, over a very short distance.

    A tube eroded by BM-15 shows similar wear at the breech, but much more extensive wear over the entire length, including very 'noisy' wear (flaking liner material?) towards the muzzle.

    The tube eroded by TAPNA has roughly half the wear of the BM-15, with minimal wear near the muzzle, and 'similar' wear immediately ahead of the bore start.

    The paper concluded that both APFSDS rounds had inadequate sabots for bore-wear consideration, but the BM-15 had additional problems including the cyclical wear near the muzzle (suggesting balloting and poor accuracy too??)

    I'd characterise BM9-BM17 as being EFC 4-5 depending on tube, and the later rounds being EFC 3-4?

    It 'looked' like the EFC isn't entirely fixed either - the wear in the portion the OF-19 round affected seemed similar for all three tested rounds, suggesting that a limit of ~800+ rounds would be capable of being fired without trouble, but that the wear on the tube would limit the useful accurate life of the tube to ~250 rounds of TAPNA or ~160 rounds of BM17

  12. :) Lieste, at least read correctly provided links which gun has what EFC before making theories ;)

    My bad... 2A26, the 2A46 is as you say 800 EFC

    So:

    2A26 EFC 350 ~ 120 rounds @ EFC 3, 90 rounds @ EFC 4, 70 rounds @ EFC 5 (The higher velocity of the early steel rounds might actually make them worse for erosion/wear reasons even though penetration is limited)

    2A26M2 EFC 600 ~ 200 rounds @ EFC 3, 150 rounds EFC 4, 120 rounds EFC 5

    2A46/2A46M EFC 800 ~ 265 rounds @ EFC 3, 200 rounds EFC 4, 160 rounds EFC 5

    2A46M-1 + EFC 1200 ~ 400 rounds @ EFC 3, 300 rounds EFC 4, 240 rounds @ EFC 5 (Chromium liner)

    It is unclear which rounds carry which EFC (and when or in which gun) - unlike the US rounds there is no clear growth in muzzle energy, rather a transformation of internal design.

    While the muzzle energy of the projectile assembly has slightly increased over time the velocity has been reduced (and presumably the pressure increased), so it is unclear what trend there is with the EFC.

    With the lower pressure limit for the earlier tubes, It is feasible that the EFC is also higher for these guns when firing higher pressure ammunition, but the increase in expected wear is at least partially taken up with higher erosion of the standard 1 EFC rounds (the EFC equivalent being a relative, not absolute value).

  13. That would be 2500 EFC for the RM120, rather than "rounds" though?

    So something in the region of 800-500 rounds of APFSDS depending on type and temperature, 2500 of HEAT or a mix thereof.

    For the L7, the HESH was an EFC of 0.5, so a similar 'life' would allow 5000+ rounds of this type to be fired..

    Which means that an early 2A26 gun might have a life of 350 EFC, yet be "gone" after 100 rounds of APFSDS

    EFC: -

    HE-Frag 1

    APFSDS 3-5

    HEAT-FS 1

    Kobra/Refleks/Svir ~0 (minimal charge to eject round and 'set' recoil buffer)

    By comparison

    M256 1500 rounds EFC (possibly at an earlier development stage - I recall some improvement to hardening to prevent flaking of the liner?)

    EFC:- (averages of 49 deg C, 21 deg C, -32 deg C {the 49C value in curly brackets})

    M865 1.1 {1.5}

    M829 3.0 {4.2}

    M829A1 3.5 {5.0}

    M829A2 4.4 {6.3}

    Of significance is a reasonable improvement in life for the early US gun over the Russian Gun, even in the later 1200 EFC versions. More significantly - all of the rounds fired in peacetime are EFC 1-1.1 for the US, while firing even 'training' APFSDS ammunition will use EFC 3 for the Russian tank - so most will not fire much of this type - tending to use HEAT-FS or HE-Frag, or even more likely sub-calibre 14.5mm projectiles as their analogue... which is probably not as useful as extensive training using all 'appropriate' natures.

    Rheinmetall published information on DM63 IM propellant, stating that wear was reduced by a factor of ~3 (presumably at high temperatures and it isn't clear how this related to EFC as such... the relationship doesn't sound linear?).

    The resulting EFC was 'reduced to levels similar to DM33', and gave a barrel life of "400-600 rounds". Suggesting that DM53 be somewhere around 130-300 rounds - my WAG from the information presented...

    Current propellant (improved) suggest ~260 rounds ballistic limit for M829A3, although the previous propellants were ~50 rounds less.

    Fatigue life of the barrel is much better - 4-5 times that of the liner material (when firing M829/DM33), but it might be more sensitive to actual number of rounds (cycles) rather than EFC (my speculation)

  14. Well, again the range is sterile - a hit is a kill, regardless of position, penetration or armour...

    That T80U might not agree to 'die' just because you put a neat hole in his third road wheel, or clip his radio antenna.

    Also on the range you cease fire on each target as it is presented and hit... but in the scenario with more uncertainty, you may kill that one vehicle 2-5 times (until it changes shape or burns)... the more shots you take the higher the probability that at least one will be an outlier, the longer the engagement takes and the fewer stowed kills each vehicle carries.

  15. With practice and in a sterile range environment, you should still be able to return a 85-90 score... Things don't go as smoothly when being 'scored' or when in a more fluid mission, especially when the hurry-up is on because that T80 just spotted you. :sonic:

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