An M-10 tank non-killer.

[The Steppenwulf]

People tend to overestimate the difference the trajectory makes in the angle of incidence. It's in the order of half to 1 degree for high velocity rounds, and rounds aren't very (usefully) accurate at ranges where the angle gets over a degree. Elevation effects and lateral angles are much more significant changers-of-angle of incidence.

Thanks for clarifiying that. Though I hope that I hadn't indicated that trajectory might be more significant than elevation. My point there was entirely theoretical, as an afterthought, and was intended to be supplementary to my earlier post regarding elevation.

Originally Posted by Redwolf: That math doesn't work for kinetic energy rounds, at least not until subcaliber depleted uranium rounds.

I'm not sure exactly what you mean here. I know little about the formulation detail and I'm entirely happy for others to do the math (as I already indicated). So long as it doesn't negate the validity of my substantive point I'm quite content.

[Redwolf]

I'm not sure exactly what you mean here. I know little about the formulation detail and I'm entirely happy for others to do the math (as I already indicated). So long as it doesn't negate the validity of my substantive point I'm quite content.

Increase in armor slope provides better, usually much better, increase in defense against kinetic rounds than simply doing the math on the direct path through the angled armor. You can use those "line-of-sight" calculators only starting with depleted uranium rounds.

This doesn't invalidate your argument, but you should know that you make your argument look instantly weak if you betray that you are not aware of this factor.

[Vanir Ausf B]

You can use those "line-of-sight" calculators only starting with depleted uranium rounds.

HEAT rounds also. The same Panther glacis plate that resists equal to 205mm vs 76mm APCBC only resists equal to 140mm vs HEAT. That is why 105mm HEAT rounds can actually penetrate the Panther glacis plate if the shooter is a little higher in elevation or at long ranges where the round is angling downward when it strikes.

[Redwolf]

HEAT rounds also. The same Panther glacis plate that resists equal to 205mm vs 76mm APCBC only resists equal to 140mm vs HEAT. That is why 105mm HEAT rounds can actually penetrate the Panther glacis plate if the shooter is a little higher in elevation or at long ranges where the round is angling downward when it strikes.

Yeah, but there is a problem is that a WW2 HEAT round. If a HEAT round starts penetrating it will go through based on line of sight thinkness rule all right. That is very nice but WW2 HEAT rounds very very likely to bounce off completely or not to have their trigger firing when hitting sloped armor. That is why post-WW2 heat rounds (such as most rounds you see on RPG-7s) have triggers that are way forward of the actual round.

So, in the case of WW2 HEAT the thickness is line of sight, so penetration suffers less from angle than AP and friends. But whether the whole HEAT thing works or not is again highly dependent on angle.

The battle of the bulge in particular has lots of reports of bazooka rounds plinging off Jagdpanzers and the like without ever doing anything.