a little question!

[Dog Soldier]

Could it be a morale issue? Quality over quantity? If the scout cars are Morale level A and the battalion of infantry is morale level D with both units not disrupted, it is quite realistic that the infantry will refuse to charge the machine guns of the AC with just hand grenades.
Another outcome is a few AC are destroyed and a number of men are killed with the rest of the infantry returning to a safe distance and the AC holding the ground. After surprising the AC and getting some teams close enough to do damage the AC inflicted enough casualties and moved within the hex in a way that caused the other infantry teams sent in for the assault to lose heart and not want to die today.

Do not think of this as the whole 600 -700 men charging the AC from all directions. When a battalion of infantry moves in close to some spotted armor for close combat, most of the infantry companies/platoons in the battalion are held back to form a reserve, guard the battalions flanks and rear and other mini-missions in the same two hours that are not visible in the game on an operational level.
The battalion commander might not inspired much confidence this turn. The infantry making the assaults on the AC failed their morale checks (in a tactical game morale checks are used to consider a host of reasons the assaulting infantry fails to damage the armored target of an assault), weapons fail, men refuse to follow orders, the target spots the assault and moves, so on and so forth.

Close combat is never a sure thing.

Dog Soldier