P60L runtime variation

Specs per SF website:

Light 6P G2 G3
Lamp P60L P60L P60L
Lumens 80 80 80
Runtime 11 12 9.42

How does adding a battery cut your runtime by 2 1/2 hours?

i've seen those same #'s and am disppointed by what i see.

the 3cell L6 burned longer than its lil' Luxeon brother the L5 (at least that's what i've read in the product pages for those lights).

if we accept these numbers as accurate, then the drive electronics must be very inefficient bucking the excess voltage, or possibly the G3L starts out brighter, or perhaps (and this could be the case, barring thermal limiting) burns brighter longer before output starts to decline. normally one would expect less current drawn by the drive electronics due to the higher supply voltage with 3cells, resulting in greater burntime (i've measured such when playing around w/various drop-ins. i'm still leaning (wishful thinking???) towards maybe SF is under-guesstimating the burntime, or some aspect of the light's brightness/burntime. haven't seen any burntime plots yet. sorry, i don't have an authoritative answer. size15's, you copy?

Theres actually a runtime chart in Surefire's catalogue (page 45, you can get the PDF off surefire's website). It seems that the P60L drops to about 70 lumens after a few minutes, and proceeds to run at that 70 for 3 hours on 2x123s, while it will run for 5 hours at 70 when driven by the 3x123s. The 11 hour runtime estimate is misleading, since 8 hours of that is at a quickly declining output (to <10) lumens.

Now that quick drop to 70 looks to be the thermal regulation kicking in, but it dosen't change the fact that your looking at about 3 hours of fullish ouput on the 6P and 5 hours on the G3. Being able to say 11/9 hours for runtime is great for Surefire's marketing division, but it in the end is misleading. The descriptions, in my opinion, should include runtime at optimal output then runtime at declining output.