Read a story about WWI trench war. Remove the instinct to hide in bomb craters because there was an order "seize that trench", remove the initiative to toss grenades or switch from rifle to small weapons to fight in the trench, remove the pain that force soldiers to fall and lay on the ground. You will have perfect targets, just fixate whatever weapon you have on the head level.  
You just made zombies with an ability to use weapons. 

A veteran soldiers would just sit in one place with a pike and stab all those soulless zombies in the face. 

It would be better to mass produce cows and equip them with bayonets.