X-Com: Gray Dawn Range Penalties
The Range listed for a firearm is its "long" range. Medium range is half that, close range is one quarter. "Close" range is one-quarter the listed range; shots fired at this range or less do not suffer range penalties. At medium range, there is a -5 penalty to the attack roll. At long range, -10, and extreme range -15. Shots fired at point-blank range (one meter or less) inflict maximum damage.
When taking a firing action, you can choose to brace and take more careful aim. This requires the shooter to sit still, and turns them into a stationary target. While bracing, you do not get to add your dodge/cover skill to defense rolls.
Shotguns and range work a little differently. They have a long range of 40m, but the nature of their spread means they are more likely to hit at longer ranges. At close range, they gain +2 to the attack roll, at medium range +4 and at long range +6. They also do less damage at greater range, subtracting one die of damage for every range bracket. Shotguns do not have an "extreme" range. At anything more than the max range, the individual pellets will lose enough potency that they will not provide substantial penetration.
A scope can only be used from the bracing stance. It will further reduce the range by another category (long becomes close, extreme becomes medium, double extreme range is long and four times extreme range is extreme). Bracing will reduce the range category by one; a shot at long range would be considered medium range. Close range shots with a rifle can be taken out to 50m instead of 25. Given time to line up a shot, the concentration perk can be added to long-range shots. To gain the +1 bonus from aiming, an entire combat round must be dedicated to aiming (not just an action within a combat round).
Long-range weapons certainly have some great advantages. Shorter range weapons also have tactical advantages that are sometimes ignored in the pursuit of bigger (must always)=better. If this were truly the case, all our police officers would always carry rifles.
Firstly, there are certain intangible (in tabletop combat) concerns which mostly affect role-playing. Long guns are difficult to conceal and/or carry around all the time. Soldiers in the field don't really care about this too much; they are often laden down with tons of other gear, too, and soldiers don't generally need to hide the fact that they are armed. For a police officer, it is difficult to deal with someone in a non-confrontational way while you've got a shotgun or an M-4 cradled in your arms. At the ref's discretion, certain skill checks may suffer a penalty based on what gear (including weapons) your character is lugging around.
Second, long guns are more difficult to effectively wield in close-quarters. Rifles require a certain minimum amount of aiming, otherwise you might as well just be laying down covering fire. Smaller weapons can be more easily aimed while in a tight spot like a small room or a hallway. Rifles will also more readily telegraph their point of aim. Shots from a carbine or rifle in close-quarters may give the target a dodge/cover bonus (ref's discretion).
Lastly, the shorter a weapon (generally), the quicker it is to get sight alignment, and the sooner the shooter will be able to put shots on target. Longer guns like rifles will require more time to line the sights up on the target. Smaller weapons trade range for utility. A carbine weapon adds +1 to initiative. SMG-sized weapons add +2, and lastly, pistols add +3. Shotguns will add +3 to initiative, also; though they are longer weapons, part of their design is that they don't require as much precision aiming. You can still snap off a relatively quick "aimed" shot with a scattergun. This is also why they are effective CQB weapons. Of course, the biggest drawback to shotguns is that most of them have very limited magazines, and they are slow to reload.
