You are good at scoring critical hits.
Prerequisites: BA +8, Proficiency with weapon
Benefit: With one particular weapon, double the critical threat range. Thus, if you had a weapon with a critical range of 20, this feat would change it to 19-20. If you had a weapon with a critical range of 19-20, this feat would change it to 17-20.
You can take this feat multiple times, but its effects do not stack. Instead, it applies to a new weapon.
Special : This feat stacks with supernatural enhancements that increase critical threat range.