Hello, i'm trying to find information of the penetration capabilities/effectiveness of tank and anti-tank guns in WW2 against pillboxes made of reinforced concrete (e.g. german Regelbau pillboxes).
So far i've only found one account that said the Flak 41 with AP round supposedly had around 1m penetration @500m against concrete - but its not specified if just regular concrete or reinforced.
Can anybody help?
I recently read an account of the fighting inland from Sword beach. A British unit was attacking not a pillbox, but a concrete-reinforced, fortified building. Shermans had attacked the building with no success, using AP rounds. An M10- probably with a 17-pdr AT gun but can't be sure as the British used both types, blew several holes in the building with AP (not APDS), allowing infantry in to assault.
There were also concrete emplacements on Jig Beach that defied attack by 75mm AP, but were smashed by the petard rounds of AVRE Churchills.
In general I would not expect standard tank gun rounds to defeat pillboxes, as this was precisely the sort of thing they were supposed to resist.
(sources: Battleground Europe series, Tim Saunders (ed)).