rechargeable 2-cell for SureFire 6P Classic

jcy1012

Newly Enlightened
Joined
Jul 18, 2020
Messages
3
Ordered a 2-cell SureFire rechargeable battery from B&H but when it arrived it was about 2mm too wide to insert into my very old 6P Classic. Is it a known issue or did I get a bad battery? It's the one that uses USB to recharge.
 

lightfooted

Flashlight Enthusiast
Joined
May 6, 2010
Messages
1,017
Unfortunately it is a known issue that you may have realized after doing a bit more research. I'm guessing you ordered a Surefire branded 18650 thinking it would fit in your very old 6P. Yes it is exactly 2mm wider...however there are single cell solutions that while they will work fine in your old 6P, they would work better with a replacement P60 LED drop-in.

You should look for 16650 cells to use in your old 6P. You will need to get a charger unit as well. The one caveat to using a Li-Ion cell in your old light, assuming it is still an old incandescent, is that you have no protection for the cell itself unless it has it built in and in that case you won't be able to just run it until the cell is too low as the protection circuit will just cut power completely.
 
Last edited:

ChrisGarrett

Flashlight Enthusiast
Joined
Feb 2, 2012
Messages
5,726
Location
Miami, Florida
Just get a naked 4.35v naked 16650 Sanyo cell, a cheap Liitokala 100 USB charger and charge it up to 4.35 volts and see what you can see.

Chris
 

Timothybil

Flashlight Enthusiast
Joined
Nov 9, 2007
Messages
3,662
Location
The great state of Misery (Missouri)
When I still had my 6P and G2, I used one of the Lumens Factory drop-ins with a 16650 cell. If you want to stay incandescent, I seem to remember LF also offering 3-4v incandescent drop-ins as well.
 

jcy1012

Newly Enlightened
Joined
Jul 18, 2020
Messages
3
Thanks for the tips guys. Total newbie here, but found my old 6P that had been in drawer for 15+ years. I'm trying to hold onto the 6P as a primary but not sink a ton of $$ into it and to keep it simple, hence the rechargeable. I haven't researched bulb conversion, but I will now!

RE: 16650. Do I need anything else, or just the battery and charger? Is upgrading the bulb (I assume 6v) recommended?
 

fivemega

Flashlight Enthusiast
Joined
Jan 28, 2003
Messages
5,530
Location
California
Bought the battery from B&H but it seems to be about 1-2 mm too fat. Does anyone know what my options are for rechargeables? Thanks.

In order to fit an 18650 battery, you may have some machinist bore out battery tube or get an readily bored out 18650 tube.
BTW, average capacity of protected 18650 (3400mAh) is way more than 16650 (2000mAh).
 

Grijon

Flashlight Enthusiast
Joined
Oct 14, 2014
Messages
1,359
Location
Midwest, USA
Thanks for the tips guys. Total newbie here, but found my old 6P that had been in drawer for 15+ years. I'm trying to hold onto the 6P as a primary but not sink a ton of $$ into it and to keep it simple, hence the rechargeable. I haven't researched bulb conversion, but I will now!

RE: 16650. Do I need anything else, or just the battery and charger? Is upgrading the bulb (I assume 6v) recommended?

The cheapest and simplest way to go rechargeable is to get a 16650 and a charger. You should be able to reliably get an hour of runtime per charge before the light starts to dim dramatically - but be aware that even at full charge it will not be as bright as on the pair of CR123A primaries that it was designed for.

I recommend that before investing in li-ion batteries and chargers, you may want to buy a 6-pack of CR123A batteries and just replace them as needed. This would give you 3 hours of actual use before needing more, and in that time you may decide that you would rather upgrade or replace the light rather than put more money into it as a primary user.

How much money are you thinking?

The 6 CR123A batteries would be around $12 online.

A single 16650 and charger looks to start around $25. That would be all you have to spend to get an hour at a time of dimmer incandescent light.

A Lumens Factory incandescent bulb that is designed to run on li-ion is in the $15 range if you want to stay incandescent. It would be bright but still limited to around an hour runtime.

A Malkoff M61WLL is an LED dropin that would mimic the incandescent P60 in appearance, but with literally ten times the battery life. It costs around $50.

With a 6P you have many many options. :)
 
Top