I was wondering if I was being too harsh on the Boys; some British weapons have had relatively ungenerous performance estimates compared to the optimistic “Manufacturer’s brochure” figures quoted by other nations. Possibly the British used stronger plate in their proof tests?
Having given the matter a few minutes’ thought over a glass of tea, I really don’t think that’s the case.
In the first place, if the British are not usually given to wild over-claims for weapon performance, still less so are the Russians. Russian official penetration figures are famously conservative, to the extent that MI 10 also gave, alongside the official figures, estimates of penetration based on British practice that were always more generous.
In the second place, as severe armour nerds might recall from a 2015 posting of mine on proof conditions for British A/Tk guns, the plate used from 1936 to 1942 had an ultimate tensile strength between 70 and 75 tons. I assume that the same plate was used for anti-tank rifles as for anti-tank guns. Further assuming that this means tons per square inch — hard to see what else it could be unless the proof plate has the strength of plasticene — this is a range of 965 to 1034 MPa, with 1000 MPa slap bang dab in the middle. Lucky guess by me, and as shown it is a good match for almost all the ATR steel projectiles of known dimensions.
It seems that the Boys did have its afficionados — Boys fan-boys, I suppose — but only really among strange special forces types. The LRDG thought it was a fun gun to shoot up aircraft on the ground, and the US Marine Raiders used it in the Pacific to shoot up, among other things, enemy boats. Those are obviously not tanks; this really corresponds to the post-war idea of an anti-material rifle. Otherwise the attitude of the Army seems well reflected in a remark reported by Zaloga from the Desert war, that the Boys was usually “given to the company drunk to carry as penance”.
All the best,