"Dead" Batteries?


Newly Enlightened
Sep 25, 2004
Not sure if this is right forum, but here goes:

My two M6's have been sitting unused for some time and I wanted to see if they would still work. I tried both lights, one with the MN20 the other with MN21 lamps, and nothing! Figured I would clean and re- grease the threads and o-rings. Put the lights back together and started to work the tail caps back and forth to work in the new grease. To my surprise, both lights started to give a faint yellow glow. A couple of days later, I decided to try the lights again. The MN20 light put out a nice, white beam while the MN21 still put out a yellow beam, but brighter than before.

Any idea why both lights started working again when it originally looked as though both sets of batteries were dead? I just got my new supply of SureFire 123's and now the MN21 is back to full, white brightness. However, the MN20 light looks so good that I have not replaced the old batteries yet! Is there such a thing as primary batteries going into a sleep mode if not used for a long time?

Thanks for all your thoughts,