14.3 it is.

Not only do Crosman say so, but I've weighed (individually !! must be mad ) best part of 1000 of the little blighters. Stats are:

Extreme spread - 14.0 to 14.7 grain
Proportion within +/- 0.1 grain of average - 84.3% (which is pretty good)
Average = 14.3 grain
Discard rate (skirt damage/malformed) - less than 1%

I usually chuck away those weighing 14.0 and 14.7 grain and batch the rest into 14.1-14.3 and 14.4-14.6, stored in film canisters in 100s (so's I can keep check on how many go through my Rapid between refills).

Have fun.

Biggles