A device for knocking out tanks.

MUST be ballistic weapon
CANNOT be rocket-propelled
CANNOT be guided
CANNOT be thrown
NO lasers!

-think recoilles rifles, high calibre rifles.

These need to be carried, and fired by a team of no more than two soldiers.

Recoil is a bitch with high calibres so you need to think of a way to minimise it (think muzzle breaks).

This gun needs to be able to take out a main battle tank.

Also you must design the ammunition. What types of round will you be firing? HEAT? Sabots?