Here is what it says thanks to babblefish:
"During the decade of 1970 they were carried out multitude of experiments with the intention to create a assault rifle - and its corresponding ammunition better than the existing ones. A line of investigation that studied in the preceding decade consisted of using very small and light bullets "microballistic", of between 1,1 and 3mm of diameter and cartridges of size of the one of pistol. The FN, in 1973, proved an intermediate concept. A bullet almost "micro" in an ordinary case of tamño. We suppose that the highest initial speeds had to be obtained, but that decrease very quickly with the distance. In fact sum the disadvantages of the ordinary cartridges (weight, volume and cost) with those of the subcalibers like 223 Rem that was causing complaints in Vietnam (reduced energy, much sensitivity to the wind and the foliage). Finally its study giveave, and we do not have the news that have gone deep much more in this line."
This is one of the typical .14-caliber sub-caliber cartridges, based on a small .223-type case. I can't see it being any worse than a .22-250 as far as barrel life goes.
