A few charts showing the effective weapon ranges and possible penetration angles for the strv 81 (Centurion mk 3) and the strv 74 when pitted against the IS-3 and the T-54. The charts have a note on them referring to what is presumably a more detailed description of these estimations but I have not been able to locate that document (yet).
Archive reference: SE/KrA/0266/002/01:H/F I/13
Note that the charts are dated 1957-10-18, but were found in a volume of documents listed as containing documents from 1956.
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