When it comes to using a ranged weapon (besides a firearm), experience shows us that stronger people are able to exact more distance out of the projectile. In the Olympic shot put, for example, the difference between two contestants whose form and footwork are identical, is their strength. Form (which may be Dex based) can produce the largest impact on final distance, but Strength dictates potential distance. In D&D 3.5 and comparable systems, the DM may opt to implement the following variant rules for ranged weapons:
A character’s strength modifier applies to the actual (base) range increment for a thrown weapon. To determine the actual range increment, divide the weapon’s base increment by 10, multiply by the character’s strength modifier (positive or negative), and add this number to the weapons base increment.
Formula: new_base = base + (Str * base/10)
For example: a character with a +3 Str modifier can throw a dagger, which has a base increment of 10 feet, a total of 65 feet (5 x [10 + 3 * 10/10]), and an enemy standing 25 feet away only incurs a -2 penalty, since he’s more than one increment away (13ft.), but less than two increments away (26ft.). The same character could throw a javelin, which has a base increment of 30 feet, a total of 195 feet (5 x [30 + 3 * 30/10]), and an enemy 100 feet away only incurs a -4 penalty since he’s at least two increments away (78ft.), but not three increments away (117ft.).
Alternatively, a character with a -1 Str modifier could only throw the same dagger 45 feet with a range increment of 9, either taking a -2 penalty to attack a foe 2 squares away, or incurring an attack of opportunity from him to throw it while adjacent to him. He could instead throw the same javelin a total of 135 feet with a range increment of 27, taking a -2 penalty on attack rolls against foes more than 5 squares away.
Neither the penalty nor the bonus applies to bows of any kind. A composite bow, however, adds ten times its strength rating to its range increment. Thus a composite shortbow [ +2 Str] has a range increment of 90ft. instead of just 70. A character doesn’t get a bonus to this for above average strength, even if his strength is higher than the rating ( +3 for instance), but if his strength is insufficient he doesn’t take a penalty to range either (it’s just that much harder for him to pull back on the bowstring).
The Far Shot feat doubles the range due to strength as well, but doesn’t increase the penalties (Far Shot doubles the final range & increment, after modifying the base range increment). For instance, the second character could take the Far Shot feat and use his throwing dagger to attack anyone up to 3 squares away with no penalty because 15 feet is within the 18ft. range increment he would attain with the feat.
For convenience the DM may opt to round to the nearest 5 ft. square. In such case, the character from example #2 (with -1 Str) would not take the penalty against an enemy 2 squares away, as that equals 10 feet, which is the nearest 5 ft. increment, but he would still take the penalty against someone 30 feet away when using a javelin, because 27 rounds down to 25. As a rule of thumb, one should follow normal rounding conventions, which is to round up in case of an indeterminate value (’3s and ’8s in this case). If the DM and players are really ambitious, they can of course apply the modular algorithm, and multiply by 2 and use base 10 rounding rules, but the results are the same.