Elzetta Design creates some of the toughest and most distinctive flashlights on the market today which, owing to their tactical nature, are specifically designed for use with industry standard CR123 lithium primary batteries.  This choice of battery type makes perfect sense when considering the intended law enforcement and military applications of these lights but may frustrate some users who would like the ability to use larger, more powerful, lithium-ion rechargeable batteries.

OVEREADY has taken steps to fill this void by boring (enlarging the battery compartment) of the Elzetta Bravo and Charlie flashlight bodies.  These bored Elzetta bodies may then be purchased separately or as part of a complete “turn-key” flashlight with the high-output AVS head. 

I purchased a bored version of the Charlie body for my personal use a few months ago.  A bored Bravo body was provided by OVEREADY for use in this review.

OVEREADY Bored Elzetta Bodies – Overview

Externally the bored Elzetta bodies look no different than their stock counterparts.  The only giveaway is the slightly larger battery compartment with an 18.75mm inner diameter versus the stock 17.33mm.

A comparison between a bored version (left) and stock Elzetta body (right) better illustrates the larger battery compartment and its effect on wall thickness.  The Elzetta Rotary switch (press for momentary, twist for constant-on) will not work reliably with the bored body due to the narrower lip.  The High/Low, High/Strobe, and regular click type tailcaps all work fine with the bored bodies.

As with other custom bored OVEREADY products, a battery retention lip at the head of the body keeps the battery (or batteries) in place when the head is removed.

18mm AW rechargeable batteries fit the bored bodies with ease.  The Bravo can now be used with a single 18650 or two 18350 cells while the Charlie will comfortably hold two 18490 batteries.

OVEREADY Bored Elzetta Bodies – Performance

The Elzetta AVS head is a nifty piece of equipment that adjusts its output based upon the voltage of the batteries supplying it.  In the 2xCR123 Bravo configuration (roughly 6 volts) the AVS head is rated to produce 650 lumens of output.  When reconfigured with the 3xCR123 Charlie body (9 volts nominal) the AVS head bumps its output up to 900 lumens.  For a more thorough description of the Elzetta flashlights and the AVS head, including beamshots, be sure to read their full review.

Runtime tests were conducted using the AVS head with a variety of battery types and sizes.  For the Bravo body, baseline tests were conducted with a selection of batteries sized to fit the stock body.

The results show that none of these rechargeable options come close to matching the regulated output and runtime of the Battery Station CR123 primary batteries.  The AW 17670 struggled to keep up and was only able to provide regulated output for approximately 11 minutes before beginning a fairly steep decline in output.  The K2 Energy LFP123 cells were able to maintain solid regulation for over 30 minutes but output began to drop alarmingly fast as they were depleted.  The KeepPower 16650 had the best performance with regard to runtime but it too showed a rapid decline in output as it was depleted.

So, can a bored body and larger batteries really make much of a difference?  Definitely.

As indicated on the chart, size does matter when it comes to rechargeable batteries.  The AW 18650 IMR cell outperformed the smaller KeepPower 16650 even though they both have the same rated capacity.  However, the AW 18650 3400mAh battery is the real star of the show and matched the regulated output of the Battery Station CR123 batteries for the first 37 minutes of runtime followed by an extremely long tapering output as the battery was depleted.  Although not shown on the chart, the AW 18650 3400mAh powered the AVS head for over 3.5 hours before output dropped to 10%.

When the Bravo body is used with two lithium-ion batteries, the AVS head boosts its output to 900 lumens, albeit with a short runtime.

To maximize output at this higher level, the longer Elzetta Charlie body must be used, allowing the use of additional or larger batteries.

As with the Bravo body, the K2 Energy LFP123 cells maintained good regulation for a while but output dropped like a rock after a little more than 30 minutes of runtime.  The AW 18500 and 18490 cells also handled the load extremely well and were able to maintain maximum output much longer than the Battery Station CR123 batteries.  However, after dropping out of regulation they do not have a long period of tapering output like the primary batteries.

After about 66 minutes of continuous operation with the protected AW 18500 cells, output dropped to the vicinity of 650 lumens and was maintained at that level for about 3 minutes.  At that point the low voltage protection circuit in one of the batteries was triggered, shutting the light off completely.  The unprotected AW 18490 cells provided nearly as much regulated runtime, 58 minutes, before dropping to the lower output level.  The test was ended at this point but the cells would have continued to provide light at this reduced level for several minutes providing some warning of the need to change batteries, disengage, or switch to a backup light.  At the conclusion of the test, the 18490 batteries measured around 3.2 volts with no load.

It should be noted that the combined length of two AW 18500 cells is slightly longer than three CR123 batteries.  As a result, two 18500 batteries make for an extremely tight fit in the Charlie body (too tight in my opinion) and may require loosening the head slightly to make enough room.  The AW 18490 cells are slightly shorter and fit without any issues.

OVEREADY Bored Elzetta Bodies – Conclusions

The Elzetta AVS head works extremely well with lithium-ion rechargeable batteries.  I expected this when using two cells with the bored Charlie body, but I was a little surprised at just how well the Bravo body and a high-capacity 18650 battery worked with the AVS head.  The bored bodies worked and fit perfectly with stock Elzetta bezels and tailcaps, with the exception of the Rotary Tailcap.  Elzetta bodies are always well machined and the boring process performed by OVEREADY appears to be up to those same standards.

The test results highlight some of the disadvantages lithium-ion rechargeable batteries can have in critical use situations.  First and foremost, when used in multiple cell configurations, these batteries tend to drop in output (or shut off altogether) with very little warning when they are nearly depleted.  Also, in the case of protected batteries, we are introducing another piece of electronic equipment (the protection circuit) and its corresponding failure potential into the equation.  This second concern is only made worse by the proliferation of cheap knock-off and counterfeit lithium-ion rechargeable batteries that are on the market today.  These are tactical lights and having one suddenly and unexpectedly shut off could be catastrophic in a life or death situation.

This is why Elzetta specifies the use of quality USA made CR123 cells for critical use.  It’s not because they make their own batteries (they don’t) or because they are stuck in the past (they aren’t) but rather for the advantages these batteries offer.  For one, quality is more consistent across the USA made brands which introduces very little variation in performance.  Also, the CR123 battery format is well established and has proven itself to be reliable in hard use situations.  Add in their long shelf life and gradual decline in output as they are depleted and the primary batteries have a lot going for them.  These are all things to consider before making the switch to rechargeable batteries.

For less critical tasks, the bored Elzetta bodies are a terrific enhancement to an already great family of lights.  A single 18650 in the bored Bravo body generates the same maximum output as a pair of CR123 cells and provides a huge improvement in useful runtime.  The bored Charlie body is impressive in its own right with the ability to provide nearly an hour of dead flat regulation at the AVS head’s maximum output level.  Whether using primary or rechargeable batteries, quality cells from a trusted vendor are a must.

For more information about the items mentioned in this review, visit the OVEREADY website or use the links to individual items below.

• Custom Bored Elzetta Bravo with AVS head
• Custom Bored Elzetta Charlie with AVS head
• Custom Bored Elzetta Bravo host
• Custom Bored Elzetta Charlie host
• AW Lithium-Ion Rechargeable Batteries

The CR123 batteries used in all runtime tests were provided by the fine people at Battery Station.  Their support has been invaluable.