School me on 18650 bored Elzetta bodies?

[napeequa55]

Can somebody explain what the trade offs would be on the bored out Elzetta bodies?

I have two elzettas as weapon lights, but would prefer a rechargeable for the gun I carry for coyote - as it will be frequently used.

What are the tradeoffs? What downside is there to running an 18650 vs the two 123s?

Basically I'm asking why wouldn't I switch over to a bored body?

I'm mostly battery illiterate so small words please.

Thanks!

 

[MX421]

How small do the words need to be? :nana:

I have an unbored Elzetta and use 16650s in it. My capacity is only 2500 mAh, but that better than the (up to) 700 mAh of the RCR123s (16340) and way better than primaries (regular disposable CR123s). Bored, you can go up to 3500 mAh and probably better over time, but 2500 mAh is good enough for me. Most of my 18650 lights use my recycled batteries which are only in the range of 1500 (sometimes less) to 2400 mAh anyway, but those were free, so i don't worry to much about changing them out and essentially half the runtimes on maximum (which i don't use constantly). Even that is better than primaries, both in terms of cost and capacity.

If you don't know much about lithium batteries, read up, they can be dangerous. As long as you have a smart charger though you should be fine.

Good luck!

 

[Grizzman]

Are you using an AVS head, or a standard head with separate drop-in module?

I've currently got one bored Bravo, with a Bravo and Charlie being bored by Oveready now. I personally consider the ability to use 3400 mAh cells vs ~2300 mAh (16650's real capacity at 4.2 volts) as well worth the $25 bore fee. When my Bravo was unbored, it sat around while the bored body was used...with constant swapping the AVS and standard heads back and forth.

The circuits of protected 18650, 16650, 17670, etc cells aren't overly robust, so it's possible for the rifle's recoil to kill the circuit, therefore killing the light's output. Unprotected 18650 Li-Ion cells can be used, but they're the least "safe" option available. 18650 cells with IMR chemistry is "safer" than unprotected Li-Co Lithium Ion cells.

If you're using a standard head with M60 or M61, it should become visibly dim long before the cell has been drained to an unsafe level. I need to verify the output of the AVS head with a mostly depleted 18650.

 

[scs]

Can somebody explain what the trade offs would be on the bored out Elzetta bodies?

I have two elzettas as weapon lights, but would prefer a rechargeable for the gun I carry for coyote - as it will be frequently used.

What are the tradeoffs? What downside is there to running an 18650 vs the two 123s?

Basically I'm asking why wouldn't I switch over to a bored body?

I'm mostly battery illiterate so small words please.

Thanks!

Output is substantially reduced on 1x18650 as a result of the lower voltage, and constant output regulation is as good as gone, IIRC.

 

[Grizzman]

Output is substantially reduced on 1x18650 as a result of the lower voltage, and constant output regulation is as good as gone, IIRC.

My measurements, confirmed by 880arm, show that the AVS head outputs approximately 500 lumens from an 18650. I happily give up tightly regulated output to not burn through primaries.

If napeequa (that's quite a screen name) is using an M60, then the output from 4.2 volts is visually indistinguishable from when it's fed two CR123s. Naturally, the tight regulation is eliminated.

Here's some reading material. http://flashlightguide.com/2014/09/oveready-custom-bored-elzetta-bodies/

 

[bykfixer]

A pair of primaries gets you regulated run time with a nice, slow dim as cells decline below the regulated voltage.
Instant darkness with rechargeables.

Plus with primaries there is not circuit interuption due to shock causing protection to kick in.

People use rechargeables all the time. But Elzetta sends them out with using primaries in mind. And until a couple more laws of physics are able to be hacked they will likely continue that.

 

[Grizzman]

Before making likely incorrect statements about the operation of a single Li-Ion cell in a Bravo, we must first know what head or drop-in is used. The M60 and M61 does not go from bright and usable light to total darkness, when using an 18650. The slow taper in output is significant.

I personally don't use Li-Ions in weapon mounted lights, using primary CR123s instead.

 

[bykfixer]

^^ same here.
And now that I've discovered the 'magazine' I preload them with fresh cells for quick change out in my oversized lights. Seconds saved swapping batteries and a nice brace around the cells to keep things nice in straight with positive contact at all 3 points (2 cell configuration) at all times.

 

[MX421]

Agreed that Elzetta (as well as Surefire and others) recommend only primaries in weapon mounted lights.

It sounds like you two are way more educated on the circuits than i. I understand that the protection circuit is what gives out due to the shock if Li-Ions are used. Therefore if i were to run this, i would use unprotected cells (i have a bravo, so only one) which is most of my battery collection. Not that i use it on a weapon much, but i plan to...

 

[MX421]

Ahh, read the thread above and i see the benefit now of boring as far a runtimes and drop-off rates are concerned. Still, if I'm going in to a situation where i will need a weapons mounted light, i would ensure i had a fresh battery after looking at that chart. Then again, in a life or death situation where i needed it, i would then have primaries. Still, i can't get away from the fact that the bored lights have a thinner wall....

Luckily, I'm not in a profession (rely on weapon light day after day) where i need to rely on primaries. I'm sure in those situations, the employer (local or big brother government) would pay for the primaries.

 

[bykfixer]

Unless you plan on driving over the light with a school bus wall thickness shouldn't be a concern post boring.

From what I read oveready gives nice accurate cuts when removing material.

Wall thickness of my old Streamlight weapon mounters is less and they're good to go on a 12 gauge.

 

[Grizzman]

The wall thickness will be approximately the same as Malkoff MD2s, Moddoolar Pockets, and FiveMega's 1x18650 bodies. These are all regarded as highly durable lights.

A negative aspect is that if you get the body from Oveready, their machine shop removes one of the tailcap threads. A positive aspect is that they replace this thread with a second o-ring slot.

Using CR123s in the bored body will allow them space to rattle side to side. Oveready (and other sources) sells Delrin sleeves to take up the excess space, but they're not free. There are lots of other ways to take up this extra space, most of which are free....except for paper currency.

 

[Grizzman]

Considering it'll output 900 lumens from 9 volts, it did quite well on the low voltage side. When the cell had discharged to 3.6 volts, it was outputting approximately 76% of the lux delivered by a full 18650. This is likely to be around 380 lumens. At this point, the output difference between it and another AVS fed 6 volts was visible when shown side by side, but not one after the other. At 3.2 resting volts, the output was obviously diminished. With the battery at 2.75 volts, the light wouldn't power on to high mode, but stayed on to a lower voltage once it was lit (by charging the cell very briefly).

Are you still around, napeequa, or did our flashlight geekiness scare ya off?

 

[MX421]

Unless you plan on driving over the light with a school bus wall thickness shouldn't be a concern post boring.

The kids all get on school buses, so that scenario is perfectly feasible :laughing: There is also the trash truck that comes twice a week

From what I read oveready gives nice accurate cuts when removing material.

I've heard that as well, i guess i'm a purist and like to keep my flashlights as they were originally made, but i may get a bored elzetta or surefire in the future after reading the article. Then again, i have some other lights that take advantage of the few +3000mAh 18650s I have, so thats a luxury at least to me.

The wall thickness will be approximately the same as Malkoff MD2s, Moddoolar Pockets, and FiveMega's 1x18650 bodies. These are all regarded as highly durable lights.

I do have a FiveMega body and more recently a MD2 (finally) and they are pretty tough lights as well. Just getting into this drop-in light stuff, so i'm still learning obviously.

Considering it'll output 900 lumens from 9 volts, it did quite well on the low voltage side. When the cell had discharged to 3.6 volts, it was outputting approximately 76% of the lux delivered by a full 18650. This is likely to be around 380 lumens. At this point, the output difference between it and another AVS fed 6 volts was visible when shown side by side, but not one after the other. At 3.2 resting volts, the output was obviously diminished. With the battery at 2.75 volts, the light wouldn't power on to high mode, but stayed on to a lower voltage once it was lit (by charging the cell very briefly).

Are you still around, napeequa, or did our flashlight geekiness scare ya off?

Do you blame him