12v Lamp & 3xRCR123... Bad idea?

I recently got an Ultrafire WF-502C (Surefire 9P knockoff) and some AW RCR123 cells. I was thinking of running the rechargable cells with the G&P 12v lamp assembly, but would this instaflash it? I wouldn't wanna blow my new light the first day I got it, but the anticipation is killing me!

Well, as you won't be able to get the voltage higher than 4.2*3=12.6 V, it should prove ok for a 12 V lamp. However, I'm pretty sure that the G&P 12v is intended for four 3 V lithium batteries, which would sag down to perhaps 9 V during load, and that's what voltage the bulb is made for. If you knew the power consumption/current draw of the lamp, I could give you a better answer here.
If the lamp is too powerful and pull too much current, you might trip your cells if they are protected too, especially at startup.

If you have more bulbs and they are inexpensive, you can always try. I'd give it a 30% chance of working ok, 50% tripping the cells, if they are protected and 20% blowing the lamp, but don't take my word for it. Someone else muct have tried this before.

Good advice.

FWIW, Nugget has run the SF M4 MN61 lamp (12V down to about 10V under load) with unprotected RCR´s in the SF M6. It apparently ran OK and these were two stacks of 3 in series, overdriving the bulb and this was still OK but will probably shorten bulb life. the idea was the same--three RCR´s voltage adding to the same 4 primaries voltage to drive the lamp. But, as previous advice the only way is to try it I don´t think it will instaflash.

The bad news: I've hot-flashed three G&P 12V lamps, each time using three 150A cells.

The good news: Two or three CPFers successfully run this lamp on three unprotected RCR123A cells without instaflashing and they love the brightness.

AW's newest protected RCR123A cells (good for 1.5A) should work, too.

If you like the P91's white wall of light, you'll love the G&P 12V; I've described it as the P91 on steroids.

I think your 150A's will hold their voltage too well under the load of the lamp. The little RCR123's will sag more making it less likely to pop.

My 12v G&P bulb hasnt popped from RCR123's yet.

Would the larger capacity of the 150A cells lead to the instaflash problem?

[edit]Nevermind, shoulda refreshed the thread before I posted [/edit]

Well, I tested it out, and it worked amazingly. Gotta love having the power of my old mag hotwire (6 cell bulb w/ 2x18650) in a pocket sized package! :rock: However, after using it intermittently for a few minutes, the tailcap got stuck and won't click anymore, leaving it stuck in the off position. Is there anywhere I can get a new switch? Getting a whole new tailcap would be nice, but I don't mind doing some soldering if someone knows where to get the reverse-clicky switches.

Paul_in_Maryland said:

The bad news: I've hot-flashed three G&P 12V lamps, each time using three 150A cells.

The good news: Two or three CPFers successfully run this lamp on three unprotected RCR123A cells without instaflashing and they love the brightness.

AW's newest protected RCR123A cells (good for 1.5A) should work, too.

If you like the P91's white wall of light, you'll love the G&P 12V; I've described it as the P91 on steroids.

Click to expand...

Sounds like it's already over driven on the primaries if it instaflashes on three 150B's, but not 3 RCR's. No wonder it is so bright. Makes me wonder about reliability and bulb lifespan.

cmaylodm said:

Would the larger capacity of the 150A cells lead to the instaflash problem?

[edit]Nevermind, shoulda refreshed the thread before I posted [/edit]

Click to expand...

Slightly less voltage sag under load because the cells are larger than the RCR's.

From this it sounds like the bulb is already operating on the edge.

cmaylodm said:

Would the larger capacity of the 150A cells lead to the instaflash problem?

[edit]Nevermind, shoulda refreshed the thread before I posted [/edit]

Click to expand...

Slightly less voltage sag under load because the cells are larger than the RCR's.

From this it sounds like the bulb is already operating on the edge.

That's a shame you needed a new switch. I just threw my UF light in the trash a week ago. I would have sent you the switch for free. The rest of the light was busted though (my fault).

Where did you get your 12v lamp? Or did it come with the light (and where did you get the light)? I've been looking for a 12v lamp but there seems to be some variations among them.

I got my Ultrafire 9P and G&P 12v bulb from an eBay seller by the name of NothingToBid. I emailed him about the broken tailcap and he is sending me a new one free of charge, hopefully this new one doesn't crap out as fast. In the meantime, I am just going to have to use my light as a twistie instead of a clickie.

cmaylodm said:

Would the larger capacity of the 150A cells lead to the instaflash problem?

Click to expand...

Not quite. The low internal resistance of the 150A cell leads to instaflashes as the voltage won't sag as much as with RCR123.

Now that I think of it, they were 150B cells (1000 mAH), not 150A (1200 mAh). I was using them in a G&P 4.5-cell body (3x123A body + 1.5-cell Surefire A14 extender). 150Bs have only a third more capacity than a typical RCR123A cell, which shows you far the smaller cells are already pushing the 12V lamp.

Are all or most of the G&P lights thread-compatible with SureFire parts (extenders, tailcaps, and such)?

cmaylodm said:

Are all or most of the G&P lights thread-compatible with SureFire parts (extenders, tailcaps, and such)?

Click to expand...

Yes. Specifically, you can mix and match Surefire heads, tails, and bodies with G&P's T (tactical) series and its clones. But not with G&P's E (Economy) series.