Surefire Fury DFT and 18650 batteries

MATTB

Newbie
Network Support I
#1
I just tried out my Fury DFT. After a function check I swapped out the CR123's for one of my P1R's factory 18650s. Clicked the tailcap.. nothing. Clicked it again and the light came on for a few seconds and then shut off. Reinstalled the CR123s and functions perfectly. Tried a second 18650 and it functions fine.
I just measured the 18650s with a carbon fiber digital caliper. The OAL length of the problem 18650 is 2.70"
The 18650 that works is 2.71". The shorter 18650 works fine in my P1R. I'm planning on marking it for P1R use only.
 

JeffM.

Newbie
Network Support I
#2
Are these the older 2600mah batteries or the newer 3400mah? The 2.7” battery and the 2.71” battery convert to 68.58mm and 68.83mm, respectively.

69-70mm seems to be more common for higher capacity button-top protected batteries. The Panasonic NCR18650B batteries mentioned in a recent post should be in the 69.5-70.5mm ballpark in length, for example.

A lot of protected button-top 18650 don’t come that way directly from the big name manufacturers. Their unprotected flat-top batteries, generally produced for use in battery packs for laptops etc, are sold to 3rd parties who then add those features, so length (and quality) can vary, even if the same base cell is used.

I haven’t found mention of who is and/or was OEMing the batteries for SF, but things can change enough over time to create issues as companies try to up the lumens while still having usable runtimes. The P1R was initially introduced with 2600mah batteries, then latter provided with 3400mah batteries (and a bump in published run time). The Fury DF might simply be designed to accommodate the higher capacity batteries being produced now that are pushing the physical limits of the 18650 size. It might be worth calling SF and letting them know about the issue. They may be willing to replace the shorter battery with a newer and possibly longer one. IMHO SF 18650 batteries should work in SF 18650 compatible lights.
 

MATTB

Newbie
Network Support I
#3
Thanks for the reply Jeff. Great post. These are both 2600s. The long one was produced 07/16 and the shorter one in 05/16. I will be on the hunt for some 3400s now.
 

MATTB

Newbie
Network Support I
#4
Now after charging the 18650 that worked last night it doesn't function. Could the Surefire charger be pushing the positive terminal in?
 

MATTB

Newbie
Network Support I
#10
When I got home from work on Friday the 18650A's were waiting for me. No more issue like what I described above. Tonight the Fury did shutoff by itself after being on continuously for about three minutes. It was warm but not hot.After cycling the switch twice( off then on) to get it back on it ran fine.
 

MATTB

Newbie
Network Support I
#13
I took advantage of Surefire offering 40% with Free Shipping for 2 18650A's or a charger with one 18650A. Two more 18650A's on the way. I mentioned this issue with some Surefire folks at the NRAAM right before running into "Matt Six Actual". They were definitely aware of it.
 
#14
Update. Old blue Streamlight 18650’s are a no go. I have two brand new 3400 mAh Panasonic 18650’s that are also a no go after some testing. Same issues, intermittent on/off only. Can’t rely on it for duty. Running 123A’s results in no issue whatsoever. Surefire cells should be enroute.


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Corey Barnes

Newbie
Network Support I
#15
At this point it seems like the general consensus is run SF batteries in the Fury DF and Scout DF and you should have no issues and any other batteries are hit and miss. No?
 
#17
Update. Been carrying the DFT as a secondary light the last few nights. The lumens are impressive with 18650’s. Using the Panasonic’s until my Surefire 18650’s show up and have been carrying another light on the belt. Using the Panasonic’s is intermittent. It almost seems as if there is a dimensional issue going on because if I get the intermittent on/off it seems to correct when I back the tailcap off a half turn, jar the body, then tighten back up. No issues for a bit then again later intermittent activation. I know there was a question of the dimension having something to do with this issue. Will further update when the Surefire cells arrive.


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Mike_IA

Amateur
WARLORD
#18
A Surefire Fury DFT is 0.10-0.122 biggier in diameter than the legacy Fury tactical. So with an appropriate amount of round file and Dremel work a new Fury DFT will fit in the legacy Surefire V70 light holster. The new light will sit higher but ass is shown in the photo it isn’t any higher than my ASP and the spring retention still works. (Belt stuff slid together for the photo, not how I wear it)
 

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