14.5 mm above i believe still capable to make damage in such sight. as i mention above you must be 500m away from the tank since 500m is best kill radius for a tank.
this task isn't as easy as what we can see at video game, and there's not much population of such big caliber sniper weapon out there. rather than use sniper to disarm tank optics, its much cheaper to use ATGM to Kill a tank.
while nowadays you can watch some footage of how rare tank periscope is damaged, unless the turret were flown away from its hull.
and please take a note, much better vision you got in a tank (latest generation of thermal, night, IR, vision) combined with automation target tracing you have much than what most of
tanks have today.
sadly our leopard RI still has second generation of thermal and Night vision, and still shared among commander and gunner. is it bad ?
mostly not, since nearby tank threat (
) has worst condition (gun , armor, ammunition, sight).
again in tank to tank (also can be read armor to armor) battle the winner is the one who can see the enemy first.
