I am thankful that the batteries menehune's must be watching over my family last night as I simply left them in the charger while playing with the M6's. I should look for those probes with alligator clips to monitor the actual charging voltage from now on.
I have an old Chinese made hand-me-down multimeter from the 90's, of which I have no clue how to calibrate or if it's even calibrate-able. That could be error source #1. However, could it have been off by a whole volt? That's like a 20% error? I will try a couple more readings on some enelops and RCR123's that I have later, as references.
Charger is a several weeks young Pila IBC unit, the one that a lot of seasoned CPF'ers recommended as almost idiot-proof.
Don't remember a whole lot from those circuits classes I had decades ago, but I do remember the this nitro-glycerine term very very well. Not sure if the FM holder puts all three cell in series, but if I made a mistake on inserting them incorrectly, could I have even gotten a reading out of the holder's terminals? I actually double-checked (maybe something I learned from circuits class) by reversing the DMM probes and did get a negative reading in the exact magnitude.
My play-time stopped last night after the bulb blew (btw, it's really a very gentle flash, nothing dramatic. No burn mark inside the bulb or on the filaments either). I have since been thinking about using the unprotected cells just for powering the M60 lamps in a C2 or 6P, or at least until I read the responses here. Supposedly, those blue unprotected cells are new and only had a couple of cycles. I want to use them because I did pay for them, but if they are wacky I don't even want to sell or give them away as they may be dangerous.
With all that said, I must say the 3x17670 + WA1185 combo definitely outshone the 6xR123 + MN 21. Unless, of course, I was playing with an almost self-exploding flashlight last night, perhaps.
With Aloha,
Clarence
bulb that I just bought. 
