Sniper vs Armoured vehicle.

[low_bidder]

Early WW2 tanks had slots cut in the armor to see out of. Any sort of rifle barrel would fit through one. Any rifle bullet fired into the interior will bounce around until it finds a soft spot ( tank crew) to rest in. Engines were covered by a grills. Some were even armored. The slots were wide enough to accept that same rifle that just killed half the crew. bullets bouncing around inside an engine compartment are bad on the engine. Wires, pumps, distributer, carburator hoses, etc. can all be disabled by a bullet. disabling them stops the tank and it's half dead crew.