Yes. The rear sight blade on a Mosin-Nagant rifle is in metric increments. Russia and the Soviet Union never used the Imperial system, nor did any country which manufactured the Mosin-Nagant under license from the Soviet Union (Mosin-Nagant rifles were manufactured in the US from 1915 - 1917 under contract from the Russian Empire prior to the Bolshevik Revolution, but those also had sights measured in metric intervals. Rifles were also manufactured for the Russian Empire in France, as well).
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