Will a Surefire G2 handle a P90?

I've replaced the lens with the UCL from flashlightlens.com, so I'm good there. The P90 actually puts out a little less than the P61, but I just want to ask to see if anyone has had any problems with the higher output lamps...

No problems here with a P90 and nitrolon. This is a setup I use pretty regularly. I've heard that nitorlon can handle the P91 without any problems too. You do need the glass lens though.

That Nitrolon is good stuff and takes heat very well. I've tried all the G2 combos, (P61, P90 and P91), and my favorite by far with the G2 is the P90 with 2X3.7V protected R123's. Great amount of light and long runtime.

Gene said:

That Nitrolon is good stuff and takes heat very well. I've tried all the G2 combos, (P61, P90 and P91), and my favorite by far with the G2 is the P90 with 2X3.7V protected R123's. Great amount of light and long runtime.

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I'd like to hear more about this. I just attached a G2 to my shotgun. I've got the P61 lamp in there now, which frankly doesn't seem much brighter than the P60 to me. (Perhaps the hotspot is bigger rather than brighter? I need to experiment more.)

Anyway, would the P90 + R123s be significantly brighter? How much runtime, exactly? Does AW sell those 3.7V cells? I'm thinking of purchasing a couple 17500s from him for my Streamlight TL-3, and could easily add some R123s if he sells 'em.

Oh, and I guess I need an UCL too. Can't forget that...

Just to piggy back, I have a G2Z with older Z24 beamshaper (flood and throw), P90 and 2x 3.7 protected RCR123s from AW. This is an incredibly fun setup. Given the latest information Silverfox has found out about peak temperatures for li-ions (100-140 degreesF) nitrolon is probably the ideal material because it retains a bit of the heat from the lamp. I also like being able to charge these cells on my Pila charger, they charge in 30-40 minutes. The only downsides to this setup that I can think of are the relatively short runtime and the double/triple tap. Other than that, it's a lot of flashaholic fun!

Hmmm, having to triple-click a weapon light would probably be a Bad Thing. I got the impression that some of the newer rechargable cells had less finicky protection circuits? Does anybody know of a cell that will "light on the first click" in the application we are discussing here?

Finally, can somebody explain how two 3.7V cells can adequately drive a lamp assembly that is designed to be driven by three 3V cells? Does a non-rechargable 123a really sag that much under load?

The P91 lamp sounds really fun. I hope that turns out to be an option!

DaveNagy said:

Finally, can somebody explain how two 3.7V cells can adequately drive a lamp assembly that is designed to be driven by three 3V cells? Does a non-rechargable 123a really sag that much under load?

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Basically the 3v primary cells have a loaded voltage lower than 3V, more like 2.7v, so 3 of them is about (3x2.7=8.1v). The 3.7v cells are actually 4.2 volts with no load, and about 3.7-3.8 volts under load, so 2 of them is (2x3.8=7.6v), so under load, both setups are "close" enough to drive the 9V lamp, although the 3xcells should give you a longer runtime than the 2xcell setup

I have personally ran the P90 and P91 on two unprotected RC123 cells and it works well, except for the short runtime as noted above. With protected cells, I have not been able to find cells that will work the first time since the initial current draw from the cold filament is too high and it triggers the cell's protection circuitry.

Will

Ah, so having unprotected RC123 cells is the key. I'll have to read more about them. Since they have no protection circuitry, you'd have to worry about over discharging them?

I also notice that there are li-ions which are twice the length of a regular 123a cell. The Pila 168s, for instance. Only one of those would fit into a G2. Would this cell be able to power a P91, or are you better off going with two RC123s?

Sorry for all the questions. My battery-fu is extremely weak.

DaveNagy,

Pilas are 3.7 volts each too. You would need two of them to power the P90 or P91. A lot of folks here like the SF 9P or C3 with two Pila 150s to power either their P90 or P91. That's how I have my M3/M3T set up (though with M3 lamps). No double taps. It seems less likely that you'll blow a P90 on li-ions, but there have been some reports of P91s going out using them. Remember that SF lamps are engineered for SF primary cells and not li-ions, so you use them at your own risk. You could look into Pila lights if you want something engineered for li-ions.

leukos said:

DaveNagy,

Pilas are 3.7 volts each too. You would need two of them to power the P90 or P91. A lot of folks here like the SF 9P or C3 with two Pila 150s to power either their P90 or P91. That's how I have my M3/M3T set up (though with M3 lamps). No double taps. It seems less likely that you'll blow a P90 on li-ions, but there have been some reports of P91s going out using them. Remember that SF lamps are engineered for SF primary cells and not li-ions, so you use them at your own risk. You could look into Pila lights if you want something engineered for li-ions.

Click to expand...

Actually there are 3.7v SF compatible LA....

Maybe this will help... :candle:


http://www.knivesandtools.com/de/help/flashlights-comparison.htm?dist=20m&flashlight1=20msfp60.jpg&flashlight2=20msfp90.jpg

enjoy!
Firebladz.

Wow, very helpful. :thanks: