Trouble measuring Ultrafire 186500 protected 4000 mah with Accucel6

Hi all,
Not sure what i am doing wrong, but I am having trouble measuring Ultrafire 186500 protected 4000 mah with Accucell6. These are the batteries:

This battery powers my $8 C8 Cree for hours at a time (~8) .
When I discharge it on NiMh setting to 3.0V, at even .1A, the voltage starts sagging fast, and reads empty with only ~200 ma.
Same when charging, at 1A to .5A, only takes from 80 to 200 mah.
It must be better than that or it would not keep the C8 lit for so long. I tried the C8 with a unprotected fully charged Sanyo and Samsung, it isnt much brighter…
I’m thinking I doing something wrong….Charger seems to work properly with the unprotected Samsung and Sanyo laptop pulls i have.

Different cell won’t give you more light but longer runtime. About the cell - you probably got one of these:

Open that UltraFire cell and post what you find inside.

You should try to measure the tailcapcurrent.
8hours…LOL this must be a nuclear powered ultrafire bat…

This is consistent the test shows the voltage sags that would mean that in the flashlight the same would happen, on lower voltage less current flows and so the light is longer working but less bright.