I assume you measured that yourself; at what amps did it (almost) hit that 5000 lm?
Yesterday I did a quick test of the FT03 I’ve modded to a SFN40 6500K (I believe) a while back and I got 16,8A (peak) at the tailcap. I’m just curious in what range the output (theoratically) might be.
I still haven’t done all the (possible) mods on that light and I used a P42A battery for the test, not a JP40/40PL, so there might still be a little more room to push it a little further.