This reminds me of a discussion I was dragged into while in Sarajevo. I had the wonderful duty of transporting our local-hire news reporters-translators to the daily NATO-UN-IPTF-HCR news briefing.
After one briefing, I was dragged into a discussion between an American reporter and the NATO press officer, a Brit Para major whose name escapes me (Chris something, good guy). The discussion revoled around American equipment naming conventions. For some reason, the reporter, in her attempt to get the nomenclature correct (an odd occurrence in itself), could not wrap her head around the fact that the M60 did not have any other name.
The M1 was called the Abrahms, and the M2 was called the Bradley, why was the M60 not called something, surely it must have a name. The NATO press officer tried in vain to tell her that was the case. "It just does not have a name, they could have called it the M60 Sausage, but they did not."
I was called over to help explain how the M60 was kind of derived from the M48, which was called the Patton and the M60 was going to be called the Super Patton but it did not stick and so forth. Her eyes glazed over and the major bought me a drink at the bar later that night.
Oh, all US nomenclature systems, despite best intentions, should just be considered random. Same with unit numbering.
paints 
