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Rattus

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    FIONNS IDEA FOR GUIDE FOR GAMERS ETHICS

    in Combat Mission Archive #2 (2000)

    Posted

    <BLOCKQUOTE>quote:</font><HR>Originally posted by Chupacabra:

    Sheesh, who dug this old chestnut out?

    <HR></BLOCKQUOTE>

    Hamsters! biggrin.gif

    Seriously, I am playing a game, a very good game that is probably much more realistic than than any other WWII computer sim I've played but still a game. I BTS have (& will continue to do) a good job limiting the effectiveness of certain sorts of gamey tactics but for the rest, it should be up to the player. If the objective is so critical, I will utilise all the resources under my command to achieve it. That call is best left to the player. This is where campaigns are so good.

    My 5c (AUD=about 1c everywhere else smile.gif )

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    Long 88mm lacking punch?

    in Combat Mission Archive #2 (2000)

    Posted

    Very interesting thread. A couple of points - and I'm no ballistics expert so please correct me smile.gif

    I understood the US Army usd the "through crack" ballistic limit until the end of WWII and thereafter introduced the "specified damage to thin reference plate..." limit. It did not use the US Navy's ballistic limit of "complete penetration".

    This means that penetration figures even for US Army equipments tested before/during and after the war are not directly comparable. I assume(!) the British tests used the "complete penetration" limit - their naval testing was obsessed with penetration with shell remaining in a condition fit to burst.

    Unless the Germans also used comparable ballistic limits the German proof figures are not comparable to those conducted by the US and UK. Different German proof test may also have had different ballistic limits. Even if they all used (for example) the "specified damage to thin reference plate..." ballisitc limt, there is enormous scope for difference in the required amount of damage to the reference plate and the distance the reference plate was positioned behind the armour plate.

    The fact that target plates have different brinnel hardnesses is another problem (I assume the plates were face hardened). If the plates were not of the same quality (metallurgical flaws, rather more important for face hardened armour than homogenous armour), if the plates were not of constant hardness, to what depth did the hardening extend - how deep was the transitional layer...Again unless these are constant between the different testers the comparisons are very difficult.

    Finally, whilst the ogive, hardness and nose height (as Paul noted) are important and will effect penetration of otherwise identical shells, the same is also true of the shape and hardness of the armour piercing cap against face hardened armour. This is complicated by the fact that the shape/hardness of both cap and shell will be more or less optimised (effective)for a particular range of impact angles. A design which works well over (say) 0-30 degrees will not be as effective over 30-60 degrees, so whether you perform the test at 30 degrees or 0 degrees is important. The shape, particularly of the cap, is also important in detemining if the shell richochets or not - especially when considering impacts at higher angles of impact. Simple scaling of results to compensate for differing slopes will not suffice even for the same projectile, let alone ones with different ogive/caps/hardness...

    My point is that proof tests such as quoted earlier by different testing bodies are extremely difficult to compare without prodigious ammounts of imformation, probably no longer available.

    The values given for the penetration of the 88/71 therfore do not seem to be inconsistent given the variables discussed above (and I did not mention shell quality, barrel wear..).

    The Jentz figures do not have to be "wrong" (or anyone else's), they may accurately represent a particular behaviour under what are unique circumstances (that series of tests).

    This might mean that CM is lousy at modelling that situation but great for the other 95% of the time.

    Since the aliies do not seem to have produced a gun/shell with sufficiently similar shape/hardness/calibre/velocity to that of the 88/L71 at the same velocity an easy test comparison is impossible.

    Michael

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    Artilery Airburst effects on tanks

    in Combat Mission Archive #2 (2000)

    Posted

    Fionn, Mike,

    Can't speak for German AP but Allied AP definitely (I'm looking at Hogg's Birt & Ami Arty of WWII, which includes many allied tank guns) adopted burster charges during the war. E.g for US 3" AT gun, M79 AP (no cap no burster) replaced by M62(!) APCBC containing burster. Similary for Sherman's 75. The US 90mm was originally issued with the solid M77 AP round - but this was declared substitute standard & replace by the APHE M82 round. The only exception was for HVAP rounds. Whilst it is true that a solid tungsten round (at much higer m/v) can cause

    more high velocity splinters (if nothing else!) than an ordinary AP round with burster, the AP round with burster produces splinters with a higher velocity and greater spread than an equivalent solid steel AP round at the same mv. That is the purpose of the burster - not to casue damage by "blast" effects. With really small rounds, the difference becomes less significant. The 2pdr AT gun had an APHE shot developed for it but tests showed it to be only a marginal improvement over the solid shot - & there were problems with losing the base fuze. Similarly the US 37mm used only solid AP shot.

    The presence of the burster makes little difference to penetration, but compared to solid shot at same mv increases lethality & permanent damage IF a penetration is achieved. A solid tungsten APCR/APDS round is travelling at such a higher mv that it's splinter causing capacity leaves the others for dead. It needs no burster to do the job disregarding the manufacturing/engineering problems with putting one in. It was the widespread adoption of the tungsten penetrator that spelled obsolecense for the APHE round.

    Michael

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    AT weapon lethality?

    in Combat Mission Archive #2 (2000)

    Posted

    At a similar range 300m-400m I saw a small proportion c10%-15% of my hits (MkIV vs Shermans) penetrate but with no significant damage, usually vs lower hull hit. The bulk of the time 1 hit = 1 kill. I assume this is partially a result of the AP rounds having burster's. I recall on of the posts the comment was made that the Brits considered a round with marginal penetration would result in a KO if it had a useful burster (on the Tiger armour thread). It would be interesting to see if older solid shot AP rounds had consistently less lethality after a penetration - as I think they have modelled this in CM.

    Not too sure about the HVAP/APDS oversupply - I think the loadout varies significantly with date. Check out ammo for 6/44 vs 5/45... but yes, unless your vehicle has a long life you won't need it smile.gif

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    What to do about a particular gamey tactic...

    in Combat Mission Archive #2 (2000)

    Posted

    Henri,

    I was not suggesting that changes were never called in - clearly in fact they were - but how often you could get away with it to non-dedicated arty resources is another issue! smile.gif Your poor old bttn mortar battery however would probably just have to comply eek.gif .

    Nor was I suggesting that you should not be allowed to make some changes to your initial arty target - I fully support that you should and I am happy CM allows it - but again it is the number of times this can be done before a fire mission lands that I am (relatively smile.gif ) unhappy with.

    Whilst I would prefer to see a limit to the amount of retargeting possible with arty I would settle for the consumption of ammo by spotting rounds. smile.gif

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