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In the Second World War, the Soviet's 57mm anti-tank cannon was capable of firing projectiles at a speed of up to 1.27 kilometers (0.8 miles) per second. Depending on the ammunition used*, German tanks could also fire at speeds exceeding 1km per second.

It should be noted that speeds were not constant, as projectile speeds decrease over time due to air resistance and environmental factors. However, as sound travels at roughly 340 meters per second (depending on weather conditions), shells from the majority of the weapons listed would reach their target before those in the area would hear the cannon fire or the projectile whistle through the air - usually, only incoming mortar fire would be audible to those in the area of impact, due to the arc of the projectile.