I don't have a Ranger in my game; instead, I have a homebrew class called 'Hunter'. One of the Hunter's class abilities is the ability to do damage which requires precision (sneak attacks, point blank shot, the hunter's own damage bonus) at higher and higher ranges as he increases in level. While the class ability can't be picked up as a feat to silo the Hunter abilities, in my opinion, this is a feat equivalent ability and since you'd have no reason not to step on the Hunter's toes you could do something like.
ACCURATE SHOOTER [General, Fighter]
You can make precision attacks at longer range.
Prerequisite: Wis 13, Dex 13
Benefit: You can add the damage bonus from Point Blank Shot up to 30' further away (normally 60'). You can also make sneak attacks and other attacks requiring precision at this range. At 7th level, your skill improves so that you that you can make precision attacks up to 60' further away (normally 90'). At 14th level, the range limitation increases to 90' further away (normally 120').
I also have this feat available in my game:
SNIPER [CLASS]
You are deadly even at a distance.
Prerequisite: far shot, point blank shot, precise shot, base attack +3, sneak attack ability
Benefit: You may use your sneak attack ability at ranges beyond 30’. You must spend at least one round doing nothing but observing your target with a readied missile weapon and you must not be detected by your target before you can use this feat. Only your first attack after focusing qualifies. You may make a sneak attack at a range of up to 30’ beyond the normal limitation, plus an additional 30’ for each extra die of damage your sneak attack does beyond the first. For each additional interval of 30’ or portion of an interval beyond the first additional 30’, your sneak attack bonus damage is reduced by one die.
With both feats a 20th level rogue could do a +5d6 ranged sneak attack at a distance of 300' (60 squares).
WARNING: If you use rules of this sort or do alot of sniping in your game, you will quickly discover the that rules for Spot are BROKEN. If you normally only use a static +1 DC/10' from the target to modify Spot, then a sniper 300 feet away will have effectively +30 bonus to hide. This will effectually make them more invisible than if they were invisible even while engaging in a sniper attack.
The brokenness of this rule can be easily observed from the fact that the difficulty to spot something actually increases according to the natural log of the distance from the target and not linearly. That is, while it's reasonable that if being 10' away gives you a +1 bonus to hide, and being 20' away should give you a +2, to get a +3 bonus should require you to be 40' away and not merely 30'. A person 200' away is only 2-4 times as hard to see as one 100' away, and thats not what happens when you add large linear bonuses in the D20 system. Consider for example the spot DC of a mountain. Obviously, missing the mountain requires failing like a DC -10 (or something) Spot check. But if you add +1 DC per 10' of distance, then the mountain is invisible to most people only a bit over 300' away. By constrast, if you assume a non-linear relationship between DC and distance, the mountain remains easily visible out to the horizon and beyond which is what we'd expect.
The stock Spot/Hide rules assume that combat occurs indoors at ranges of no more than 60' or so (dungeon distances). They will not work for you in any other situations.