If you're within range, then hits are scored on rolls of 1,2 or 3, regardless of the Gun factor. Range is also always limited to the current visibility, which fluctuates throughout the battle as dust and smoke take their toll. Having the two different systems to resolve ranged fire does a nice job of modeling the interaction between weapon and target types. After all other Movement and Fire is concluded, units can engage adjacent enemy units in Close Combat by moving into their hex. This fire is resolved at a range of 1 hex and any attackers who are suppressed must return to their original hex and do not participate in the Close Combat resolution.
German units can call for artillery support during entry fire.
Note the range of 1 hex specified for Entry fire, many units in the game have a range of zero and therefore cannot fire at all until Close Combat is actually joined. Close Combat itself is resolved simultaneously, with preference given to combined arms. In fact, many armor units cannot target infantry unless they are accompanied by friendly infantry. This lets the Soviet player recreate the historical tactic of using artillery and ranged fire to suppress the German infantry and then close assaulting any unescorted German armor that comes forward alone. Unfortunately, the rules for Close Combat are poorly worded, or outright omitted, this paragraph draws heavily on the errata.