Effects of non-explosive armor piercing rounds on tanks

Good Day,

I've always been a bit of a WWII history buff. I know the rounds tanks used against each other during the war were armor piercing but non-explosive. In other words, it was like a large bullet. An explosion can result due to the fuel and ammunition in the tank. However, if the round didn't hit the fuel/ammo, and none of the crew was hit directly, what was the typical damage to the tank and the crew? Did the crew typically survive with little or no injuries? I read somewhere the steel of the tank where the round hit was pushed inward and fragmented somewhat.

Cheers

 

Some AT rounds carried a charge.


And this/these contemporary reports/photos may interest. Plenty on spalling, strike types, crew survival etc.:

11th Armoured Division, Tank Casualties, 1945
2nd Recce Battalion Welsh Guards, GAD, Tank Casualties, 1945
1st Battalion Coldstream Guards, GAD, Tank Casualties, 1945
2nd Armoured Battalion Grenadier Guards, GAD, Tank Casualties, 1945

(I think D might have added a few more in the meantime, but possibly not.)

~A

(Oh, and hello.)

 

Some armor piercing rounds did have a small amount of explosive filler. This was most common in German ammo if memory serves me correctly. I am not sure that it was particularly effective as getting the fuse to work right with such a high velocity round was tricky.

 

A lot depends on the details. If the armor is light enough compared to the penetration capabilities of the round you may get a fairly simple through and through penetration with little spalling. On the other hand the round could pentrate with signficant spalling then the round and fragments could bounce around inside the vehicle for a while. Even a non penetrating hit could cause spalling and/or project rivets at some velocity inside the tank if it was of riveted construction.

 

Likewise....there are MANY examples of "wrecks" being policed up after a days' fighting....the human remains removed...and them being fixed and put back into action.

For example - the Vickers' MkVI light tank driven by Roy Farran (later of SAS fame) during its last counterattack into Galatas on Crete i support of the Maoris; riddled by armourpiercing MG fire previously, Farran described it as a "doilly", seeing more daylight than steel when he looked around! Montefiore's "Dunkirk" records several incedents where antitank rifle and heavy MG fire caused German tankers to abandon their vehicles as the rounds penetrated....bt later able to reclaim them!

If penetrating rounds or spalling DIDN't hit something that went bang....or something squishy!!!...ALL you had was a tank with a hole in it.

 

The OR team at 21 AG report No 12 was an analysis of 75mm Sherman Tank Casualties between 6 June and 10 July 1944. This analysed a representative sample of 75mm tank casualties from 2nd British Army with the proportions matched to the figures recorded by REME. 89% of tank casualties were from AP shot, which brewed up - burned out in 82%. It took an average of 1.63 hits to knock out a Sherman. About 5% of 75mm shots hitting a sherman failed to penetrate. So a knocked out Sherman was usually burned out.

The report recorded that in a later battle, Op Bluecoat, one unit suffered a much lower proportion of brewed up tanks to penetrations. 1 Coldstream Guards from the Guards Armoured division reported only one brewed up tank from 20 casualties, of which 12 had been penetrated by AP shot. This unit reported that they carried no ammunition outside the armoured bins. In no case has the extra outside applique armour resisted any hit and therefore the protection afforded by keeping the ammunition in the bins is because it stops flying fragments inside the tank penetrating and igniting ammunition. This should not have been a surprise, as a similar problem had been identified as the cause of catastrophic explosions on dreadnaughts.

So the answer to your question is that if the round penetrated the hull or turret armour it would be accompanied by the very hot and very fast fragments of the armour. If the shot missed the crew then it would could damage whatever else it. The hot fragments of armour would penetrate anything soft and squishy or unarmoured. If these penetrated the cartridge case of a tank round then the tank would most likely burn.

Tanks which had not burned out were reconditioned. Any crew casualties or their remains were removed. Tanks might be spayed with bitumen to hide the smell. The holes were plugged broken fittings replaced and the tank sent back into action. Leslie Skinner, padre of the Sherwood Forest Yeomanry kept a diary. Some of the entries include comments such as "..three bodies inside firmly welded together. Managed with difficulty to identify Lt Campbell. Unable to remove bodies after a long struggle - nasty business - sick"

While this makes grim reading, with the implication of immolated tank crews, there is another set of statistics which tells a slightly different story. The attack by three armoured divisions of VIII Corps on Op Goodwood on 18-20th July cost the 12 armoured regiments 413 tanks, of which 104 were reparable within 24 hours and 345 either taking longer than 24 hours or total losses. The human cost was 449 casualties (117 killed, 281 wounded and 51 missing). So there was only one fatality for four tanks out of action or for three tanks out of action for longer than 24 hours, and just over one casualty for each tank out of action. Given that on we know that sometimes a tank would explode and killing all five crew members, most of the time a tank was knocked out, most of the the crew must have been able to bail out unharmed.

Serving in armour was ;less dangerous than as an infantryman.

 

I added the file to gallery on Talk
http://ww2talk.com/forums/gallery/album/205-tank-casualties-survey-nwe-1945/
There's text and tables and all sorts of stuff folks might want to use in... discussions.

Crew members were also killed exiting or while out of their tanks, by SA fire etc, so associated fatalities didn't necessarily happen inside the tank or indeed from hits 'on target'.

 

During the war different types of AT ammo were used. Some were indeed like a big massive bullet or a dart (sabot round) which due to a larger calliber gave more energy to a smaller projectile. These use penetration too knock out there target. When hit metal fragments can fly around inside the target and the heat may set the target on fire. A second way to knock out a target is by burning a hole into the armor with hollow shaped charged (HEAT) projectiles. A third way is to use a soft high explosive (high explosive squash head) which hits the target and when exploding makes pieces of the armor from the inside fly every trew the compartment.

The germans had a preference for the hollow charge ammo because it could be used for soft and hard targets and the penetration is not bound to the distance. Due to the lowwer weight of the round the accuracy was less then the normal AP round. For the most heavy targets (KVI/II and JS) the germans saved thungsten AP rounds which where rare. Thungsten was hard to come by for the germans during the war.

 

A couple of minor points.

Actually HEAT rounds rely on KE to penetrate. The "slug" or "jet" gets most of it's energy from the shaped charge and not the propellant though.

HESH or HEP (High Explosive Plastic I think). One is UK usage the other US I never can remember which is which.

It wasn't so much the weight of the round that decreased accuracy. The rounds like HE rounds weren't as sturdy and so were usually fired at a lower velocity or used in lower velocity guns. This meant the target had more time to move especially at long ranges and that the range estimation had to be more accurate. HEAT rounds, especially WWII ones, were also more effective when fired at lower velocities as the "slug"/"jet" had more time to form. Modern HEAT rounds have stand off fuses to allevieate this.

 

Thanks for the responses all.

 

@Sheldrake: Thanks for your generous response,

Interesting to compare armor to infantrymen. Even though infantry was more dangerous, something good is an individual infantryman had more control over his safety, I guess.

 

Telly Savalas had the whole top of his turret blown off in "Battle of the Bulge" and continued to fight

 

Well he had gone topless for years anyway!

 

The Panzergranate 39, that was the most common German AT round has an explosive content (APCBC-HE-T) while the allied rounds were solid shot, always wondred if that had any correllation with the Sherman/Ronson story, going by common sense a HE content should increase the likelyhood of fires.

IIRC
APCBC-HE-T = Armour Piercing Capped Balistic Capped Hight Explosive Tracer (wow!)

For obvious reasons the shell was base fused not nose fused.

BTW I found some info hanging around the net that the Germans uses uranium instead of tungsten in some Panzergranate 40 (APCR) production batchs in 1944 , an obvious forerunner of the modern DU penetrators, any conformation on that?

 

Speer ordered captured Belgian uranium ore processed and used for this process, but IIRC the totals of various types/states of uranium found after the war roughly correlate with what was taken in 1940, so there can't have been much actually used for this purpose The total included a lot of metallic uranium, so this must have been what was processed.

 

Speer the architect (building design architect)?

 

My understanding is that unless you have special equipment makeing Uranium penetrarors is very hard on your machinist.

 

Uranium will burn if it gets hot enough and is in small enough pieces (like machine turnings). Modern production is done in an inert gas atmosphere. Machining it will also release a certain amount of alpha particles which could get in their lungs and lead to cancer.

Reply to HEP/HESH comment -- US is HEP, Brits used HESH. Fairly low velocity rounds, base fused. Idea was to smack the C4 against the turret and cause the inside to spall. I've seen a piece of 6" armor showing the spalling -- it could be like a hand grenade going off inside turret. Not healthy for squishy things and could lead to excitement if it hit ammo.

The Israelis learned to use HEP in their 105mm M-60s by Indexing Coax on the computer but firing HEP to hit enemy tanks at 3000m with a HEP round on top of their turret.
They also installed the 105mm in some Shermans -- seems they had to turn the gun sideways to make it work but they made it work.

RE Shot/Sabot KE rounds. There is some discussion about what happens inside the turret hit by a KE round. If you have the weight and velocity data do the math, then ask yourself where all that energy goes. Huge amount of heat generated for a small space, plus the concussion and spalling.

Question: what was the metal in the "shot" rounds? Was it just hardened steel or was it a special alloy?