AT and Armor Ratings

[neptunus]

Looking for information concerning how ratings were developed in the original equipment database. I have been playing with BioEd and trying to figure this out. It seems to me that the armor ratings for most WWII era tanks are based on the average of the 0 degree "RHA equivalent" for front/glasis and turret front, divided by 10. Is this correct, or just an accidental finding? My calculations seem to confirm this case for the major US, UK, German, and USSR tanks and AFVs.

AT and tank guns however seem to be more random to me. My first thought was RHA penetration data at some distance, but I can't calculate anything that makes sense on a consistent basis. Based on the luck I seemed to have with the armor data, set about looking-up and calculating "0 degree RHA equivalent" for various guns at standard test distances. I realize this is much more complex as it requires some assumption concerning ammunition and range for any given gun, but when trying various combinations I can't seem to find any apparent application of a "rule". For example, KwK 42 L/71 gun (Panther tank) penetration at 1000m is 128mm for APCBC round and 172mm for APCR round (RHA @ 0 degree); AT rating is 13, so it looks like APCBC (best "available" AT round, Germans had fewer APCR's) at 1000m (reasonable distance). This seems to work for the majority of German AFVs, but not for any of the major UK, USSR or US tanks (all of which seem to have "over-rated" guns. The vast majority of these guns do not seem consistent with penetration data at 500m or 100m for any of the available AP rounds (including the later APCR of APDS rounds); one exception seems to be that the US 3" and 76mm guns (AT = 16) would match the 1000m penetration data (156mm) for the M93 HVAP round (available only after August 1944?).

Any insight? was there a "rule" applied for ratings? How were HEAT rounds considered?

[JAMiAM]

It seems that you've pretty much deduced the general rules. Exactly why there is variance on some equipment from that rule is anybody's guess. Norm came up with these rules some ten years ago, and what criteria he used in augmenting the values beyond those you've found is known only to him. My guess is that the over-rating of the Allied AFV's is due to the fact that the game was originally intended to model Korean War era encounters and that the stats are for those later model versions.

As far as HEAT weapons, unless a weapons system uses that type of projectile almost exclusively, the projectiles are considered kinetic. For HEAT firing weapons, if the opponent's armor is rated separately for HEAT, then it uses that specific value when facing HEAT. Otherwise, it uses its rating against kinetic weapons.

[neptunus]

Thank you, confirmed my guess.