In the age of high-quality, dependable firearm-mounted lights, the handheld light remains an indispensable tool. In both police and armed civilian scenarios, it is common for the good guy to start the engagement without their pistol in hand; good guys are most often reactive to the threat.
As great as mounted lights are, they are often not the appropriate tool for the task at hand. If you are searching for a known bad guy or have other reasons to believe that there is an imminent threat, then a mounted light is the clear choice. However, the good guy is usually investigating something that falls below that imminent threshold, meaning that the search is happening with a handheld light and the firearm is holstered. This is where most professional training has let the shooter down.
When I was taught the traditional Harries flashlight technique, it was with a structured, numbered draw count. This is done to ensure that the shooter doesn't cover their support hand and flashlight with the muzzle of the gun. It's a good place to start, but most training never progresses past that. That's a huge problem because most of the time, that searching light will be in front of or above the shooter, not held tightly against the body. During real-life engagements, this means that the shooter is drawing from an unfamiliar position and can end up covering that support hand in a rush to get into the handheld technique of their choice. In force-on-force (FOF) scenarios, I have even seen shooters shoot themselves in the support hand. It also leads to sloppy, less effective techniques, contributing to many shooters' poor low-light shooting. Fighting in low light is very different from structured, square-range shooting in low light, and this fact seems to be lost on many shooters and trainers.
During the low-light package that is taught at the SureFire Institute, students are given instruction on multiple one-handed flashlight searching to shooting techniques. These include the old FBI technique and the neck or jaw index positions. The FBI technique requires the light to be held up and away from the body, ostensibly to give the bad guy a target to shoot at away from the good guy's vitals. In the age of 1,000-lumen retina burners, this aspect of the technique may be questionable, but what is not questionable is that this is a great searching technique. It allows the searcher to angle the light and utilize the corona and spill to accomplish the bulk of the work while leaving the center hot spot off reflective surfaces. If something of interest is caught in the corona, then it's easy and reflexive to place the hot spot on whatever you want to give some of those additional lumens.
When using the off-body searching technique, it's best to keep the beam out and away from your body and at a downward angle until you need to adjust the beam to your terrain; whether that is a tree outside or a file cabinet inside, the technique remains the same. By the way, if you ever hear an instructor tell you that "all you need to search inside a building is 200 lumens," I'd question their motives because they're probably sponsored by a company that only makes 200-lumen lights.
The off-body search technique is the beginning of a complete set of low-light techniques. From the off-body search position, I bring the light back to my jaw in a jaw index position if I encounter a threat. The jaw index should be the support hand pulled tightly into the jaw or neck, with the hand clenched into a fist and the thumb of the support hand activating the tail cap switch of the light. We'll get into the switchology of your light in a bit, but keeping that fist clenched against the jaw and the elbow tucked into the body as close as possible is very important.
This position accomplishes several things, including clearing the support hand out of the line of fire, illuminating the sights of the pistol, and putting the support hand and elbow in a decent defensive position in the event that the attack is happening in extremely close quarters. Another thing that I've observed during FOF training events is that even untrained shooters will often move to a half-assed jaw index when startled and under stress, drawing and punching the gun forward while bringing the light to their upper chest or jaw and blading their body toward the threat. From an instructional standpoint, it's always easier to build on a reflex than trying to completely retrain a movement.
Consider the jaw or neck index position to be a transitional shooting position, i.e., each movement should flow from one to the other. As the shooter searches with the light in front of or away from the body, once a threat or perceived threat is identified, the beam is turned on the threat while bringing the light to a tight jaw index. Simultaneously, the shooter draws their pistol and brings it on target. The light is then illuminating not only the threat but also the sights of the shooter's pistol.
The shooter's body shouldn't be bladed, but pushing the primary side scapula forward, or "punching" the pistol onto target, while slightly canting the sights inboard can help achieve a more stable one-handed shooting platform. Regardless of how well a shooter shoots one handed, two hands allow greater control of the pistol. Once the threat has been immediately addressed, the shooter should transition to a Harries flashlight technique, where the back of the support hand is pressed against the back of the primary hand, creating isometric tension to help control the recoil of the pistol.
The Harries technique is also misunderstood, and I have seen instructors move shooters from an isosceles shooting position into a Weaver shooting position to accommodate the Harries. This is nonsense! The underlying principle behind the Harries technique is isometric tension. This tension can be created in the isosceles by bending the elbows slightly and rotating them downward. There is no reason to move a shooter from Iso to Weaver — that's weak instruction by people who don't understand principles and simply regurgitate dogma. Avoid these trainers.
The last technical thing that I want to talk about is controlling the switchology of the flashlight. The best way to run a light is with a tailcap switch. Under stress, there is no rotating of the light to find a side-mounted switch. As soon as one grabs the flashlight, the thumb automatically indexes to the switch. It's fast, reflexive and repeatable. As far as the type of switch, I prefer a constant-on, or "clicky," switch. I understand the arguments against them, which is that you might inadvertently click it to constant on under stress, but that's an easy fix. Just click it again. I appreciate the ability to keep the light in the on position quickly if I need to, based on the tactical issue at hand, such as keeping the light directed on a threat during a reload so that the people I'm with can continue addressing the threat. Like anything else, try both types and decide what's best for you.
But what about firearm-mounted lights? If I'm going into an area with a high likelihood of needing my gun in hand, I'm going to be running my mounted light. Handheld techniques are not for those situations. But sometimes things don't go as planned, and bad things happen to those unprepared.
Fighting in low light is tough. It's unforgiving and scary, and your training should reflect that. If you have not yet availed yourself to serious low-light training, I implore you to do so. The SureFire Institute and Gunsite Academy are two training centers that I can recommend. There are also several independent trainers, such as Steve Fisher at Sentinel Concepts, who do great work.
Make sure that there is a robust FOF segment of training in the class; things that work well on the square range might not work as well when you're getting blasted with Simunitions. It's better to find out in training than when it's for real. Commit to the lifestyle, go get trained!