16650 in surefires?

yearnslow

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Probably been covered somewhere on this forum, but do 16650 batteries fit into surefires', like the 6P and C2L?

Thanks!
 
Probably been covered somewhere on this forum, but do 16650 batteries fit into surefires', like the 6P and C2L?

Thanks!
16650 batteries will physically fit in 6P but voltage of single 16650 is less than pair of series primary CR123A.
16650 batteries may or may not fit in E2E, A2 and such sized bored out flashlights.
 
Probably been covered somewhere on this forum, but do 16650 batteries fit into surefires', like the 6P and C2L?

Thanks!
They fit in my stock 6P and three E2E bodies but didn't fit in my L2 Lumamax (until I modded it).
Hope that helps.
 
Ok thanks guys. I didn't realise that they were that underpowered compared to 123's.

That's sort of a vague word.

A 123 cell is 3v and ~1500mah of capacity, yielding 4.5 watt hours of energy. Two of these in series gives 6 volts and 9 watt hours.

A single 16650 runs at 4.2v and 2500mah, giving 10.5 watt hours.

Yes, I neglecting to calculate voltage drop. This is napkin math.

That said, if your light is tolerant of 4.2 volts, 1x16650 runs just fine.

I've used a 16650 in a surefire L4 for ~15 years. Just upgraded the head to something more modern... the 16650 works like a champ.
 
Ok thanks guys. I didn't realise that they were that underpowered compared to 123's.
If you're looking for a rechargeable option. SureFire, and Watson make 3.0 volt RCR123s. If looking for a single-cell option, a bored out 6P to fit an 18650 is still the best bet. E-series, honestly not sure.
 
If you're looking for a rechargeable option. SureFire, and Watson make 3.0 volt RCR123s. If looking for a single-cell option, a bored out 6P to fit an 18650 is still the best bet. E-series, honestly not sure.
These are not direct substitutes. Especially in multi cell lights. They may work or may not. But I would call them a one for one option
 
Ok thanks guys. I didn't realise that they were that underpowered compared to 123's.
Its not that dramatic of a difference. They do produce a slightly dimmer light if you compare them side by side but its not extremely different, to me at least. I use them in 6Ps, LX2s, and Kromas
 
@yearnslow - Follow the good advice given here, and go for it! CR123s are great, but I really got tired of throwing away so many when I used them every day. Since I 'switched' to Li-ions, a key advantage was that while with 123s I never knew how much run time I had available in my pocket / holster when I left the house (unless I had just changed them), but w/ Li-ion, I always know I'm leaving with fully-charged run time. I may know how much I expect to need, but can't ever know how much I might need. Sure spare cells work, but only when one has time / circumstances to change them. Life doesn't always provide time for that.
 
@yearnslow - Follow the good advice given here, and go for it! CR123s are great, but I really got tired of throwing away so many when I used them every day. Since I 'switched' to Li-ions, a key advantage was that while with 123s I never knew how much run time I had available in my pocket / holster when I left the house (unless I had just changed them), but w/ Li-ion, I always know I'm leaving with fully-charged run time. I may know how much I expect to need, but can't ever know how much I might need. Sure spare cells work, but only when one has time / circumstances to change them. Life doesn't always provide time for that.
Really off topic but….This is why I love cradle rechargeable lights. The nicd type. I know they're huge and heavy and low capacity, but my polystinger will give many hours of excellent throwy light. And it's always fully charged. Always. No need to take out the batteries. And it's better than a usb rechargeable lithium ion light
 
Really off topic but….This is why I love cradle rechargeable lights. The nicd type. I know they're huge and heavy and low capacity, but my polystinger will give many hours of excellent throwy light. And it's always fully charged. Always. No need to take out the batteries. And it's better than a usb rechargeable lithium ion light
Here here! My Strion incan was a total game changer for me (well over a decade ago), along with the original Strion LED which followed it, and the latest Strion LED [DS HL) I bought just this year!;-)
 
Ya. I haven't tried a mag charger. But I have a stream light ultrastinger. The 200w incan one. It's just a light Sabre. I've build better lights. But it's still there. Always at 100%
 
Ya. I haven't tried a mag charger. But I have a stream light ultrastinger. The 200w incan one. It's just a light Sabre. I've build better lights. But it's still there. Always at 100%
Factory incand UltraStinger hass 10W halogen bulb.
These are not direct substitutes. Especially in multi cell lights. They may work or may not. But I would call them a one for one option
These are regulated 3 volt nominal RCR123A
As long as battery length fit and load is not over 1.5A will work just like primary CR123A without overdriving.
 
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I do use 16650 in my Surefire lights and they fit perfectly fine in my book. Perhaps, they produce a bit less lumens, but having in mind all of them are being used for utility purpose 100% of the time it is not an issue by any means.

More of that both 6Ps in my pockets right now have been modded (drop-ins) they output their 1000+ lm perfectly well.

The 100% original Fury (600 lm one) performs sufficiently as well.
 
Factory incand UltraStinger hass 10W halogen bulb.

These are regulated 3 volt nominal RCR123A
As long as battery length fit and load is not over 1.5A will work just like primary CR123A without overdriving.
FM. 200w was a typo. Not sure how that happened.
As far as the regulated batteries…..say in a 9p. You're saying 9v going into a p90 is fine, when it's designed for 7.5v? That's a lot of overdrive. That bulb won't last long
 
Every 2 cell SF I own other then the new DFT series has a 16650 in them any 3 cell has 2x 17500 cells in them. And I have a few no issues for years of use. I little less output but longer runtimes makes it worth it and I'm not buying primary's for daily use.
 
Every 2 cell SF I own other then the new DFT series has a 16650 in them any 3 cell has 2x 17500 cells in them. And I have a few no issues for years of use. I little less output but longer runtimes makes it worth it and I'm not buying primary's for daily use.
Same. Gotten to the point I buy only half a dozen CR123 primaries a year, just in case. For daily use, one of numerous 18650 or 21700 powered LED lights.
 
As far as the regulated batteries…..say in a 9p. You're saying 9v going into a p90 is fine, when it's designed for 7.5v? That's a lot of overdrive. That bulb won't last long
Each of mentioned battery in post #15 will drop to 2.5 volt and 3 of them will not flash a 3 cell bulb or P90 which works perfectly with 7.5 volts.
That voltage drop is not because of load but from circuit which is inside each battery.
However, for P90 bulb in 9P body pair of 17500 or pair of 18500 will work better if bored out for 18mm cells.
You can use your bored out 9P body with 35mm ExCap and pair of 18650 and enjoy the lloonngg run time and white bright beam of P90 or P91
 
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