What’s the highest amount of ranged attacks a pure fighter can make in one turn consistently?

I’ve been working on a 20th level character concept for a while and trying to optimize it for use in a future game, the requirements would be as follows:

  • Only 3.X WotC handbooks (No 3rd party books, no magazines, no online-only content except for web enhancements of handbooks, no adventure-specific content).
  • Only handbooks from the D&D 3E standard setting/Greyhawk (no eberron, faerun, dragonlance, etc).
  • The only base class used must be fighter, any prestige class is ok as long as it doesn’t grant any magical abilities (includes psionics, incarnum, etc), also no martial powers.
  • Optimized for ranged damage output, without relying on allies, consumables, or very low frequency abilities (1/day stuff and the like).

Given that, the concept I’ve got so far is a pure SAD dexterity fighter dual wielding auto-realoading hand-crossbows, boosting damage with feats Dead Eye and Crossbow Sniper, plus specialization and mastery feats. The damage per attack is not too bad (1d4+31), and I’m now looking for ways to increment the number of attacks I could make.

So far I get 4 attacks from BAB, 3 from TWF, 1 from Rapid Shot, and 1 from Haste, for a total of 9 attacks.

I’m specifically looking for methods to increase the number of attacks per full attack action. But I’d also welcome any general advice to improve the build given the previous requirements.