A lot of gear (with the exception of augmented snapshot gear) simply lists snapshot bonuses as "enhances snapshot effect" which isn't very helpful we just know it's a positive bonus of 1% or more.
With the Aurore Beret I assume the value to be 4% same as the haste, but I got an Impulse belt today and it has no real indication of it's value. So nothing is jumping out at me on the internet about testing and I have no real way to conclusively test it myself what with the ficulty of Ranged delay due to lack of auto-attack function and Rapid shot randomness etc.
If anyone has anything on the value or there best guess from experience would be nice.
Right now based on the degree of difficulty in obtaining and it's level I'd guess it was 2-4% and I intend to use it anyway for tp gain but would be nice to know an exact value if anyone has come up with one.
The real question though is why do we not simply recieve the benefits of haste (a well labeled and visible stat value on gear) with ranged attacks, appart from a semi immunity if you will to slow which we'll often be out of range of anyway or absorb with a shadow (if non aoe) what was the thinking behind this lol.