armour penetration

Hi,

I'm looking for some opinions on the relative impact of an AFVs armour being penetrated by AP projectiles. Nigel Askey's Barbarossa volume 1 gives the following information on the average number of hits to knock out tanks in NW Europe 1944-5:

Tiger 1: 4.2 hits to knock out, 2.6 penetrations to knock out
Panther: 2.55 hits to knock out, 1.9 penetrations to knock out
Panzer IV: 1.2 hits to knock out, 1.2 penetrations to knock out
Sherman: 1.63 hits to knock out, 1.55 penetrations to knock out

Taking 2 extreme examples:
a 7.92mm PzB 38/39 could penetrate 30mm at 30 degrees at 100m
an 88mm FlaK 18 could penetrate 93mm at 30 degrees at 500m

A penetration by an 88mm AP projectile is likely to be terminal. A single penetration by a 7.92mm AP bullet will be extremely lucky to be terminal.

Is anyone aware of any methodology for comparing the relative impact of penetration? My inclination is that the greater the calibre of the penetrating projectile the greater the chance that penetration will result in the AFV being knocked out.

Interested to hear other opinions on this.

Cheers, Neil

 

I don't have any opinion but I did learn about the PzB 38. Pretty interesting. Higher velocity than the .300 Weatherby but not by much.

Panzerbüchse 39 - Wikipedia

.300 Weatherby Magnum - Wikipedia

 

Comparing an 88mm to a 7.92 is really apples and oranges.

The 88 fired a 9.4-kilogram (20 lb) shell at a muzzle velocity of 1,000 m/s (3,280 ft/s) vs 10 grams at 1,210 m/s for the PzB 39.

The fact that production of the PzB was halted after 15,000 units in favour of the Panzerfaust and variants (6.7 million) gives you a good idea.

 

I believe we've got a couple armor penetration threads elsewhere, maybe this one could be merged.

I should say that from everything I've read the whole subject of WWII armor penetration is highly complex and equally confusing. All sorts of figures get bandied about.

 

I don't understand the reams of paper and bandwidth devoted to calculating the theoretical penetration of every type of shell at every possible range and at every degree of slope. Being a simple soul if I want to work out if tank X was vulnerable to gun Z then I look for examples of tank X holed by gun Z and if I find any examples then the whole calculation thing is moot.
Don't even start me on the range test results of wonder-gun A firing its second shot at a target with the range known precisely, with a crew of crack gunnery instructors then being used as if was the expected result for every first round fired in combat.
AHF has lots of highly technical threads devoted justto the 8.8 cm performance

 

Tank penetration itself says absolutely nothing about the effect on the target. The German army learned this lesson when the first tanks appeared in the Great War. Even numerous hits with the 7.92mm SmK ammunition often had no noticeable effect.

Either I achieve an additional destructive effect inside (HEAP, HESH. MESH a.s.o.) or I put a lot of kinetic energy into the projectile - one reason why the Eight-Eight was so successful (but also cumbersome)

The respective "philosophy" also plays a role:
During WW2 the Wehrmacht used AP, which went "right through" to destroy technical components. Soviet AP's, on the other hand, were feared because they fragmented and often wrought terrible havoc among the crew.

What is often forgotten, apart from the pure penetration effect, is the shock wave: "passive safety" as in modern cars is something you look for in a tank in vain. Depending on the caliber, this then causes severe bruises, cuts and even broken bones, leaving the unfortunate guys trapped helplessy inside the wrecks....

from the purely mathemathical perspective:

source: Dipl.Ing. Franz Kosar, pg. 11-12, Panzerabwehrkanonen 1916 - 1977, published by Motorbuch Verlag, Stuttgart

 

Having spoken with some surviving WW1 tankers back in the 60s and read various accounts by tank crews they certainly had a noticeable effect on those inside the tanks

 

As always a matter of perspective:
The soldier who shoots at such a behemoth desperately wants the thing to stop, or better yet, to explode
If this does not happen, the actual carnage he causes inside the tank is of no use to him at all as his weapon seems completely useless

In my active time with the Panzergrenadiers the Soviet BMP were considered "cookie jars". Until years later such a "cookie jar" drove into our position during an exercise in Poland: If you only have an assault rifle yourself, the difference to a 60 tons Royal Tiger becomes purely academic

 

This 'rabbit hole' takes you ultimately to comparing different techniques of making armour plate, wartime inconsistencies and eventually to arguing about "Shatter gap" on social media and such.... There in lies madness.......Turn back now, before it is too late....

 

Very well said, indeed
As a concluding comment from my side a wise advice of my former sergeant concerning anti-tank defense:
Every anti-tank weapon has two basic weaknesses:
The designer who claims it goes through any armour
and
the fool on the front line who really believes that

 

Could lead to a mine shaft gap!

 

I suppose a bigger lump of metal has more mass that can break up and be distributed inside a tank, but even then it all depends on the material composition of the round. You really need a shell that has enough integrity to penetrate, and yet sufficient brittleness to disintegrate as soon as it gets inside.

The best method for destroying enemy tanks is to spread rumours that leaving loose rounds arrayed around the turret is the most effective way of fighting.

 

You making a wargame or computer game or some such? As elsewhere you're asking for some detailed technical items in tank protection. I've got no issues with that, but it enables me to give better advice.

I think, somewhere, I have the formula's that were used to produce charts like this:


But keep in mind that as soon as they became available the department for Operational research started using computers, simply due to the sheer number of calculations involved.

For example, in your table, you're averaging hits to kills. and you state that an 88mm would get an automatic kill.
First off, how are we counting hits? Second off define a kill? There's a world of difference to holing a tanks armour, which would likely cause everyone to abandon tank, to popping its turret off in a fireball. One is a total kill, the other is a temporary kill. Its a kill for the purposes of the battle, and likely the mission. But it could be back in combat within a week or two.
There are studies on hits/kills/type of warhead/causalities, there's a couple focusing on 21st Army group (which I really want to track down). But you'll need to narrow your definitions a bit, and give us a bit of info on what it is for.

 

I'm designing a game for Operation Crusader (Nov 1941). According to War Establishment at that time a Commonwealth infantry battalion would have 23 Boyes anti-tank rifles. A Boyes at 100m can penetrate something like 23mm of vertical armour. They might penetrate the armour of a Pz II from the side and Axis armoured cars etc. But, going back to my original point; penetration doesn't necessarily mean the AFV is knocked out and I assume that the smaller the calibre of the penetrating projectile the less the chance that the AFV will be knocked out.

 

Actually its Boys not Boyes

It's not just simple penetration that's important but also how much velocity is maintained afterwards, an AT round ricocheting inside an armoured vehicle may do quite a bit of damage - particularly to any crew member encountered. Also important is how many fragments of the vehicles hull it sends similarly bouncing around at high speed. Small calibre AT projectiles were more likely to disable the crew as to destroy the tank. When the first AT rifles were produced in WW1 AT riflemen were issued instructions to aim for the cab where the driver sat.

 

What sort of game? Computer, table top, boardgame? I ask so I know how much we're abstracting here.

 

Its a re-design, for use by me and my friends; of GDWs 1978 game Operation Crusader. Its principally a battalion level game but does feature a lot of company level units and some platoon level ones too.

 

In that case, I'd stick ATR's in as either generating some form of suppression, or more effectively roll it into the close assault side of things.

 

Even if they couldn't penetrate an AT rifle might be able to damage tracks and stop a tank that way. Maybe?

Also for what it's worth I don't think much will be fired at range of just 100m in the desert.

As Listy said if there is some separate value for close assaults it could be folded into that.