Something else to remember is that the West Germans had a rather large military which would translate into a rather large number of weapons and all the support that entails.
Yes, it was a large investment, but one that was well worthwhile in my opinion (and obviously their's prior to reunification). Who knows, the rest of Nato might have seen the wisdom of the 4.7mm caseless round and today it might have become the standard (except of course for the Americans, stuck fast on the idea of the 5.56).
It is interesting to note however that their reservists were to be armed with a conventional 5.56mm weapon. My initial impression is this was due to the vast stockpiles of 5.56 Nato had stored in the country, although as their standard weapon until then was the 7.62 G3....
