Original sentence: The original specification called for the vehicle to be armed with a  autocannon, however an innovative combination of the 73 mm 2A28 "Grom" low pressure smoothbore semi-automatic gun firing rocket-assisted projectiles and the newly developed 9S428 anti tank wire guided missile (ATGM) launcher for the selected 9M14 "Malyutka" (AT-3A Sagger A) ATGMs
Edited sentence: The original specification called for the vehicle to be armed with a  autocannon, however an innovative combination of the 73 mm 2A28 Grom low pressure smoothbore semi-automatic gun firing rocket-assisted projectiles and the newly developed 9S428 anti tank wire guided missile (ATGM) launcher for the selected 9M14 "Malyutka" (AT-3A Sagger A) ATGMs