Eclaireur wrote: ↑
Wed May 13, 2020 1:54 pm
I cannot see how you can reach any other conclusion then that a jet from a HEAT round is *more likely* to over-penetrate, ie go through, a target like the side of a Sherman turret than a solid shot is.
Because the jet from a shaped charge is only effective over a fairly short distance (usually under about 1m-ish). To be fully effective a shaped charge has to detonate at the correct standoff distance. Too close and the jet doesn't form properly and doesn't penetrate. Too far and the jet loses cohesion and again doesn't penetrate. Indeed, many methods of defeating shaped charges such as ERA rely on this fact, they cause the warhead to detonate too far from the armour, which severely reduces its effectiveness. The Munroe Effect really only works properly within a critical distance, beyond that the jet breaks up and becomes ineffective.
Generally speaking, the jet from a shaped charge will disperse on the inside of the armour after penetrating. I'm not going to cast doubt on your conversation with the M48 guy because I'd need more info to understand the situation, but even if it did happen like that (and it may well have) then that would be a highly unusual event and you it's not something I would cite as evidence of the typical behaviour of shaped charges.
In short, shaped charges do not typically penetrate any further that one side of the vehicle, even when you've got a severe overmatch. Not saying it never happens because weird stuff does happen in the real world. But normally, no. I'm not just shooting from the hip on this. I've made my own shaped charges, and to do that I've had to study how they work. I've seen how they work.
KE rounds do very often go through both sides. Which is exactly why you don't shoot them at light vehicles. You shoot your HEAT at them, because it works much better. It goes in one side and annihilates everything in there.
But the main reason was a greater destructive effect.
It really isn't. The reasons KE tank guns are still around are those you mention: faster time of flight leading to shorter engagement times and higher rate of fire. Tankers know that whoever hits first generally wins, so they don't want to be lobbing slow large diameter rounds when the other guy could be returning fire at Mach 5. This Americans flirted with the idea of a missile tank with the M60A2 (using the system from the M551), which was a bit of a flop, one of the several critical flaws being the slow engagement time. Lack of lethality of the warhead was never an issue.
I think CoC's AFV damage mechanism actually works ok. Any severe overmatch of armour is likely to be catastrophic (in-game this means significantly more strikes than saves, 3 or more and you're dead). What it doesn't actually try to do is accurately model impact and penetration in any realistic fashion. It assumes that all penetrations are somewhat equally deadly, which I think is a very reasonable simplification. The reason for that is that the mechanism the round uses to penetrate probably isn't as important as you're suggesting. Any time an incoming round has enough smash to get through a steel plate (especially on late war vehicles) then the energy released in that interaction is going to be extremely dangerous for any flimsy bags of spam wearing uniforms on the other side. Much of what does the damage is metal from the armour itself and the thermal effects of dumping all that kinetic energy into it. Human bodies really are pathetically frail when you're looking at events that energetic.
There's really no way you can knock a hole in a tank that isn't going to be bloody lethal to the crew. Heck, sometimes you don't even need to penetrate, just expend enough energy on the other side of the armour and they'll all be turned to jam anyway.
So I'm fine with equating penetration distance to the likelihood of knocking out an AFV myself. You don't want to start getting into any more accurate modelling than that in a game IMO.