20 mm Solothurn got used in small numbers by Germany. 1936 it was introduced into the Hungarian army, Italian infantry battalions had three each. German Rheinmetal produced an export version for Romanian, Dutch and Finnish army. Sweden had some, the Swiss had just 58.
It had a better penetration but weighted more than double compared to the German Panzerbüchse 38 and 39. 40 mm maximum penetration was good but for transport the barrel was taken out, two man carrying the weapon. So a wheeled version was made too.
In the literature the valuation is mixed. Good penetration, but it was expensive and not easy to operate. Aiming and hitting was not easy. And the kick was awful.
Against modern tanks it was as useless.
The Soviet 1941 14,5 mm PTRD had a similar penetration and weight was not 50 % of the Solothurn. But the time for the AT rifle was running out. Panzerfaust / RPG 1, Bazooka, PIAT etc. made it obsolete.
And the big ……. 😉
The Finnish made 20 mm Lahi had no better penetration than the Geman 7,92 mm ones.30 mm at 100 meter. So I would not name that house rule balanced.
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