There are two problems related with ranged attack damage:
1) The ineffectiveness of a critical hit
2) How the actual damage-per-shot delt does not match the base DMG of the weapon fired.
A very simple example of how much ranged damage suffers in comparison to melee would be comparing two weaponskills: Blade: Hi and Heavy Shot.
Blade: Hi - 4.0FTP 60%AGI WSC. Can critical hit.
Heavy Shot - 3.5FTP 30%AGI WSC. Can critical hit.
Blade: Hi has an offhand hit, effectively giving it 5.0ftp. Thus we can say Blade: Hi has 1.5FTP and 30%AGI WSC over Heavy Shot that makes it stronger.
But on the flip side, Blade: Hi is also done with a 50DMG (roughly) weapon. An equally strong Gun would be performing Heavy Shot with around 160DMG. That's over 3 times higher. On top of that Heavy shot uses fStr2 instead of fStr. Essentially this means for every 1 Base Damage you get from adding Str+ on Blade: Hi, you gain 2 base damage on Heavy Shot. This goes right up to the fStr cap. a Weapon Rank 5 katana will cap fStr at 13. The fStr2 cap on a Weapon Rank 6 Gun caps at 28.
Let's say we're in abyssea with capped fStr and about 220 AGI (80 Base, 50 from cruor buff, 50 from Gnarled Horn, 40 from equipment). The base damage of the two weapon skills will be:
Blade: Hi - 50+13+132 = 195 Base Damage
Heavy Shot - 160+28+66 = 254 Base Damage
Now we're comparing 1.5ftp against 50-60 Base Damage on the weaponskill. I'm in no way saying Heavy Shot should be stronger on paper than Blade: Hi, please don't think that for a second. Blade: Hi also has the other benefits of being a melee weaponskill: Double and Triple Attack. Sadly for Rng and Cor, Double Shot and Triple Shot do not proc on weaponskills.
However the point I'm trying ot make is that if Ranged attacks worked in a similar way to melee attacks then Heavy Shot shouldn't be terribly behind Blade: Hi. But ranged attacks are calulted differently, critical hits add very little damage, and even with the enormous Base Damage on a weapon (Armageddon (85) + Dark Adaman Bullet or Oberon's Bullet: 138 DMG for Cor and 166DMG for Rng) and even with the fact that STR's increase on base damage is double that of a melee weapon, the actual damage per shot we deal is still only on par with much lower DMG melee weapon
With Critical Hit/Dmg atmas, Heavy Shot should be a very strong weapon skill, but it's not. It's very average and even with said Crit Dmg/Rate atmas averages out about equal to Slug Shot, which can't critical hit and is also a very average weaponskill compared to the critical hit melee ones available
A few years ago you made a very significant fix to Two-handed damage calulations. It's about time you made another fix to ranged damage calulations too. This should be looked at regardless of the other problems Ranger or Corsair are faced with. (Rng and Cor issues are not for discussion here)
It is no wonder this has not been brought up seriously before. There are only two ranged attacking jobs, one of which (ranger) is so flawed that only die-hard fans still play it, and who's voice alone has not been enough to shout out for this change. Now there's this outlet for communication with the development team, it's time that this was addressed and the ranged damage calulations were fixed.
The tl;dr:
1) We have enormous DMG weapons compared to melee jobs, a Empyrean Rng has 166DMG Gun. The highest dmg melee empyrean is Drk which has a measly 127DMG. (Lv85 versions). The actual damage-per-shot of a Gun does not reflect this at all.
2) Critical hits add a very insignificant amount of damage compared to a melee critical.
I'm sure you can see the problem face by rangers and corsairs who have to pay gil for their damage (antlion arrows are 20k a stack, dark adaman bullets are 40k a stack, oberon bullets are 80k a stack) just to deal damage that is much weaker than a melee's. Cor at least has a 2nd purpose to make up for their poor damage and high cost - the can buff the parties. Rangers, on the other hand, have nothing. Ranger's only purpose is to deal damage and yet it's damage is so far behind a melee's, whilst having to pay extra gil for ammunition, it's not even funny.
I know I mentioned ranger's pitfalls a few times within the post, but I did not touch any of it's issues apart from that last point, I would ask we please keep this thread on the topic of the ranged damage calulations, and not to do with ranger and corsair's personal issues. You can venture into the ranger or corsair forum to see any of that.