I was hanging out with the guys behind Dead Air Armament a week or so ago and while we may have been sleep deprived and slightly intoxicated, we had an idea. Silencers work great when it comes to sound reduction, but how well do they work in terms of flash reduction? Well, we were in a cabin in the middle of nowhere, had a bunch of rifles, a handful of silencers, and a reasonably competent photographer (yours truly), so we decided to try to capture the difference on film. The results were pretty interesting . . .
I decided to set up the camera to have about a 1.5 second exposure for each image. This would give plenty of wiggle room to pull the trigger, and capture the entire muzzle flash in one image. Slow motion video of a muzzle flash usually shows a rolling ball of fire effect, but I wanted a way to show that entire flash in one still image. What you see is basically a composite of the entire muzzle flash ball-o-flame, which gives an excellent idea of the shape and intensity of the flash in one glance rather than having to make a GIF of each video and leaving things up to interpretation.
That first picture is the “control,” if you will. We removed the muzzle device from a 16″ barrel AR-15 rifle, and shot with just bare threads. This is what you would see if there were no muzzle devices on the rifle at all, which was honestly brighter than I expected.
Next up is a Colt Competition muzzle brake. This device is designed solely to reduce the recoil of the firearm, and no design effort went into any flash reduction capabilities. What you see is a nice bright flash, and you can even clearly distinguish the different blast chambers on the brake. Definitely better than the bare muzzle, but not ideal.
Just real quick, a word on how flash hiders work. Muzzle flash occurs when the unburnt powder and other combustible materials in the exhaust from your barrel (along with the blazing hot exhaust gasses themselves) mixes with the oxygen in the air. When the proper air-to-fuel mixture is reached, it burns and creates the flash you see in the top image. Any muzzle device will interrupt that mixture process and disperse the burning gasses to cool them down, but exactly how well it performs that task will be based on how well it interrupts that combustion process.
The Dead Air Armament folks have come up with their own muzzle brake / silencer mount that has some flash reduction capabilities. Instead of trying to disrupt the mixture process with a chunk of metal, they decided to try and use a port on the side of the brake to blow that flame out just like a kid blows out his birthday candles. It redirects gasses from inside the device along the side, and should (in theory) snuff out most of the flash along the side of the brake.
There are two versions of the device, a 5.56 sized one and a 7.62 sized one. So naturally we tried both.
The 5.56 brake definitely has a smaller “halo” of brightness around it than the plain Cold Competition brake, but you can also see the impact those gas jets are having. There’s a ton of small sparks flying all over the place, almost definitely the result of that lateral force imposed by the gas jets. The overall effect is good for signature reduction, but still not ideal.
The 7.62 version of that same muzzle brake / silencer mount shows an interesting result. There’s a visible cone of flame on the front of the 5.56 version, but it appears to be almost attached to the brake. With the larger hole of the 7.62 version, that cone of flame has been pushed out a couple inches in front of the brake. The same shooting sparks are still visible and present, but with the exception of the placement of that front cone there doesn’t seem to be any real difference in the size or intensity of the flash.
Right, enough faffing about with muzzle brakes, time for the main event.
The Dead Air Armament team makes two fast attach silencers, the Sandman-S and the Sandman-L. I’ll be bringing you a review in a few days time, but suffice it to say they are pretty cool. The difference between the S and the L is about 2 additional inches of baffle stack, which reduces the sound of the report by about an additional 4 dB (I’ve personally tested and confirmed this, not just some manufacturer’s claim here). But does it also reduce muzzle flash?
Keep in mind that we’re testing the first-round flash here. There’s some data to indicate that with subsequent pulls of the trigger the flash is reduced due to the lack of oxygen in the silencer itself, but we aren’t testing that today.
Let’s start with the shortie.
There’s definitely some flash there, and it definitely seems to be brighter than the flash we’ve seen with the muzzle brake. Smaller than the brake-free barrel, but present nevertheless. The brightness is probably due to the high concentration of the combustible materials — with nothing to spread them out, they clump together at the end of the can and burn brighter.
Huh, that SilencerCo brake thinger might not be completely useless after all.
This one is the Sandman-L silencer. Two inches longer, but those two inches make a huge difference. Note that these last two pictures were taken from the same distance away, and were cropped to the same size before posting (you can see an album of the raw images here). The difference is night and day — nearly a 75% reduction in muzzle flash with just two additional inches of baffles. That’s pretty cool.
Do silencers reduce muzzle flash? Yes, yes they do. Do they eliminate it? Heck no, at least not for the first round. In fact, it might actually be worse than the muzzle brake alone. But the noise reduction coupled with the flash reduction is nothing to sneeze at.
I gotta try this with more cans . . .