Indeed, the standard deviation of muzzle velocity of 1990s production GP11 is typically between 4 and 4.5 m/s (13-15 fps), depending on the batch, and with a match barrel it typically stays within the 10 ring of ISSF target at 300 m (10 cm); in Switzerland the ammo is routinely used for 300 m CISM/ISSF standard rifle competition.Years ago I disassembled 10 rounds of GP11. Measured bullet weight, ogive, powder charge. case, overall weight, neck concentricity etc.
For mass produced ammo, it's darn near a hand load in consistency. At least the lot that I measured. Pretty impressive as it's typically referred to as "surplus".
For a bulk military issue cartridge, GP11 is insanely well done.
BTW, RUAG restarted the GP11 production lines in 2017, after more than 20 years break. This new production is just as good as the old one (and, regretfully, it is still berdan-primed).