A Working Man's AR-15 weaponlight - 2 Experiments

glock24

Gunny Sergeant
Full Member
Minuteman
Sep 14, 2006
2,043
49
West Michigan
My latest build project has focused on minimizing the weight and bulk of my next carbine. Instead of dismissing the few extra ounces here and there on every component, I tortured the numbers over and over, trying to minimize the mass and bulk as much as possible. Special thanks to Vuurwapen for the information he provides about component weights.

My investigation has now turned to the weapon light I will use for this low-drag build. Compact and lightweight are still the primary considerations. The usual suspects include the crown jewel, a Surefire M300A Scout light. I really like this light because of the light weight and small size. Using only one CR123A battery shortens the body tube significantly as well as allowing it to drop some mass. I’m not a fan of pressure switches; instead I favor a tail cap switch. That is good news because an M300A with tail cap switch and Gear Sector Scout light mount mount produces a setup that weighs only 3.9 ounces. That is very impressive.
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(Surefire M300A w/ Gear Sector Scout light mount)</span>
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What are not impressive about this setup are the cost and performance. As everyone is well aware, Surefire weapon lights are the most expensive. The M300A retails for $335, and that is before the $60 Gear Sector mount. While I’ve been known to swallow high costs on some components, the aspect that ensures I will never slide the credit card on this particular Surefire light is the lack of horsepower. The M300A only produces 110 lumens. Frankly, that is pathetic in this day and age, and I refuse to accept it. Two hundred lumens is my benchmark, but I can only get that performance in Surefire’s M600C Scout light. Of course this is at the penalty of a longer, heavier package, more money, and an additional battery. (2xCR123A). There must be another way.
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<span style="font-weight: bold">Option #1</span></span>

Refusing to pay more for less, I decided to check out some other options. I knew I wanted a compact light, and that meant using only one CR123A battery. That decision led me to the currently obsolete Surefire 3P. This light was basically the little brother of the universally-known Surefire 6P. The Surefire 3P however was half the size and used only one CR123A battery. Everything else was identical to the 6P including the P60-sized bezel and tail cap. It seemed like a perfect solution except for the lack of availability. Fortunately, the popularity of the Surefire 6P light has led to many aftermarket clones. A couple of these clone manufacturers still produce a 3P body. The two I found were the Solarforce L2M, and the Anglefire A1M. Yes, these are Asian copies of the real thing, but since the real thing isn’t around, I have no problem substituting.

At this point I needed a P60-sized drop-in that was designed for a single, 3V lithium CR123A battery. I found two choices, the inexpensive Solarforce LC-1 drop-in, and the moderately expensive Malkoff M31 drop-in. Both of these drop-ins are designed to power the LED with lower voltages, but without giving up light output or run time. Both units produce just over 200 lumens out the front of the lens. The Malkoff is American-made with a lifetime warranty, but for this experiment I decided on the cheaper Solarforce drop-in.

I like to run my weapon lights at 10 o’clock. It makes for very easy activation with the thumb of my left hand, and being higher on the rail keeps any barrel shadowing to a minimum. Even though this 3P clone is a bit bulkier than the Surefire Scout lights, I didn’t want to feel like the light was hanging out in space like some weapons light mounts can do. Keeping the light positioned close to the rail is an important consideration when moving in a building, or keeping the carbine from snagging on seat belts when exiting a vehicle.

The mount I chose was the Gear Sector 6P light mount. I really like this series of mounts due to their sleek, low-profile design, and light weight. This 3P clone fit perfectly at the end of my mid-length Omega X rail. It is obvious Gear Sector designed this light mount to hug the rail as tight as possible. This setup with battery weighs 5.3 ounces. Yes, a bit heavier than the M300A setup, but with easily 100 more lumens, more run-time, and much less money. The beam quality of this drop-in is as good as any of my Surefire lights. It has a nice white center with a gradually dimming outer region. There are no dark rings or spots in the beam.

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<span style="text-decoration: underline"><span style="font-weight: bold">Option #2</span></span>

One thing I haven’t mentioned yet is the difference between a weapon light and any regular old LED flashlight. For me, that difference is battery retention. The reason all of Surefire’s lights are so widely regarded as weapons grade is because they utilize compression springs at both ends of the battery terminals. There is a spring in the tail cap, and another spring at the lamp assembly. This dual-spring configuration not only creates a more reliable electrical connection during bumping and jarring of the light, it also helps prevent the batteries from smashing into the sensitive electronics when the flashlight experiences recoil. When any weapon is fired, all things attached to it are jarred forward. In the case of a flashlight, the batteries accelerate until they are stopped either by a compression spring, or the circuit board of the light. I’ll take the compression spring any day.

Below is the typical design configuration of a non-weapons grade LED flashlight. The positive end of the battery simply rests against a copper terminal on the back of the circuit board. I prefer to follow Surefire’s design of using a compression spring at this location.

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That said, I present the JetBeam Raptor RRT-0 Rapid Response Tactical light. This is another one of my choices for a suitable Surefire M300A alternative. Starting with the recoil problem I just described, JetBeam designed all their RRT lights with a dual-spring system via a spring-loaded brass button that makes contact with the positive battery terminal at the lamp assembly. A standard compression spring is in the tail cap. JetBeam also incorporates a plastic guard that physically separates the electronics from the batteries. These two provisions are there to counter the effects of recoil, and because of them, I deem this flashlight weapons grade.

Jetbeamhead.jpg



Yes, JetBeam is another Asian company, but unlike most, it is clear they are actually designing innovative flashlights instead of just cloning someone else’s work. What attracted me to the RRT-0 was its use of a single CR123A battery, and the small and compact size. I was pleasantly surprised however by the recoil resistance and the great price (~$100).

I was also pleasantly surprised by the unique rotating ring that adjusts the light’s output! Limited to only their most expensive models, Surefire adds what they call “navigation lights” to some of their dedicated weapon light platforms. While I have no experience with them, it seems logical that there are times when dimming a weapon light would be necessary. The two examples I can think of include navigating (duh!) known areas, and conserving battery life. The RRT-0 comes with four output settings. While I certainly don’t need four, because grabbing and rotating the selector ring is so darn easy, I don’t mind. I’m also ecstatic that they chose not include a strobe setting. I have yet to figure out the use of a strobe setting on a flashlight.

Because the RRT-0 has an unusual body profile, I found the mounting options a bit challenging. I wanted to mount the light in the center of its body tube, which is 0.843” in diameter. If that wasn’t unusual enough, the body tube is one-piece, meaning the larger diameter tail cap does not come off. The battery is replaced by unscrewing the bezel assembly. This design unfortunately prevents some traditional mounts from simply sliding on the body tube and clamping to the flashlight.

In the end, I stayed with my Gear Sector 6P mount, and I am having a machinist friend build me a pair of Delrin spacers that fill the gap between the body and the mount. In the meantime for this experiment, I used a wrap of electrical tape to hold the light. I’m also sure a properly sized rubber hose would work if someone wanted to spend an hour at Home Depot. Luckily for me I have the resources, so I figured Delrin spacers would be the most professional. Maybe someone should try and talk Gear Sector into making spacers for other flashlights?

Fully loaded, this combination weighs in at 4.5 ounces. This particular RRT-0 also uses Cree’s latest LED, the XP-G R5. This gives me around 250 lumens for 1 hour. The run time would increase to 3 hours if I choose to reduce my output to 150 lumens with a simple twist of the selector ring. With two spare CR123A batteries stored away nicely in my MagPul grip, I’m happy with having only one hour of burn time on the highest setting.

I can tell this JetBeam is brighter than my Surefire 3P clone. Its beam however is also more “floody”, and doesn’t throw as far. I’m told this is due to the smaller reflector head and inherent properties of the smaller (but brighter) XP-G R5 LED. Even though this light uses the same Gear Sector 6P mount, the smaller diameter and more compact size make seem like it hugs the rail even more. Actually hugging the rail more could be a problem because it would make activating the ring selector more difficult. In its current position with this Gear Sector 6P mount, I can find and turn the selector ring very easily, even with gloves.


<span style="text-decoration: underline"><span style="font-weight: bold">Conclusion:</span></span>

I think both options exceed the performance of the Surefire M300A at a fraction of the cost. I’m partial to the JetBeam solution right now, only because it isn’t as bulky, and is a little lighter than the 3P clone. Only time will tell if the JetBeam can handle the 1000s of rounds I plan to give it, but I’m confident enough to give it a work out.


<span style="text-decoration: underline"><span style="font-weight: bold">Summary of Specifications</span></span>

<span style="font-weight: bold">Surefire M300A Scout light</span>
Battery: 1xCR123A
Weight with Gear Sector mount: 3.9 ounces
Output: 110 lumens
Runtime: 1.3 hours (total time before falling below 50 lumens)
Approximate Cost: $335 plus mount


<span style="font-weight: bold">Surefire 3P clone (w/Solarforce drop-in)</span>
Battery: 1xCR123A
Weight with Gear Sector mount: 5.3 ounces
Output: >200 lumens
Runtime: 1.5 hours (total time before falling below 100 lumens)
Approximate Cost with Surefire components: $50 plus mount


<span style="font-weight: bold">JetBeam RRT-0 Rapid Response Tactical light (XP-G R5 version)</span>
Battery: 1xCR123A
Weight with Gear Sector mount: 4.5 ounces
Output: 255 lumens
Runtime: 1.0 hour @ 255 lumens (or 3.0 hours @ 150 lumens)
Approximate Cost: $100 plus mount
 

rrflyer

Gunny Sergeant
Full Member
Minuteman
Feb 7, 2008
1,739
69
39
DFW, TX
Re: A Working Man's AR-15 weaponlight - 2 Experiments

nice setup...i've always just used a 1 inch scope ring a standard surefire light....its enough to nearly blind me from the reflection in the hallways as is!
 

christian77

Sergeant
Full Member
Minuteman
Re: A Working Man's AR-15 weaponlight - 2 Experiments

Great post...I've been teetering on the brink of buying a SF Mini-Scout Light, but was having a hard time swallowing the price tag on something I don't use often...the Jet Beam looks like a great alternative for a compact tac-light.