Suppressor Back Pressure Testing Part 1

Overview

A good suppressor isn't determined just by sound reduction, back pressure plays a huge roll in how your rifle will function (or not function) once a suppressor is attached. In this video we tested 22 different suppressors with a 16" AR15 using PMC XTAC 5.56 55gr to determine the amount of back pressure each suppressor creates. We utilized the Riflespeed gas control system, which allows 12 levels of adjustment, to determine the amount of adjustment needed to reliably obtain bolt hold open. See the list below for a full list of all the suppressors tested.

Skip To Video Topic

Intro - 00:00
Purpose - 00:40
Cons of Back Pressure - 01:11
Test Parameters & Setup - 02:28
Best Low Back Pressure Cans - 05:55
Full Test Results & Data - 07:43
Closing Thoughts - 08:14

Full List Of All Suppressors Tested:

Huxwrx Flow 556K
Huxwrx HX-QD 556
Huxwrx Ventum 762
Surefire RC3
Rugged Alaskan360Ti
KGM R-6
KGM R556
Dead Air Nomad 30
Dead Air Nomad L
Surefire 212 Mini
Rugged Razor 556
AAC Mini-4
AAC 762 SDN-6
SilencerCo Omega 300
Otter Creek Labs Polonium
Otter Creek Labs Polonium K
Otter Creek Labs MK12
Innovative Arms Grunt-M Mini
Dead Air Nomad TI
Dead Air Nomad LTI
SilencerCo Omega 30 Cal ASR
SilencerCo Omega 5.56

Video Transcript:

Hey everybody, Rob Orgel, and as you look at what you see in front of you, you say, "Man, that guy's a nut job and has way too many suppressors," and you're not wrong. In this video, we're going to take 22 silencers and put them head to head for their biggest drawback of suppressors, in my opinion, which is back pressure. We're going to find out which of these suppressors has the most optimum and minimal back pressure and which ones are just way over the top with gas in the face, tearing up too much back pressure. In future videos, we'll talk about how to mitigate that back pressure as well. Several more suppressors are already on their way given our first batch of videos, so make sure you like, comment, and subscribe so you don't miss any of our future content. The goal of this video is to gain a great understanding of how much back pressure each one of these suppressors is giving us. Therefore, we can figure out what we can pair it with or what suppressors will need mitigation and what doesn't really need mitigation. Goal of the video is understanding what back pressure is and what cans deliver the most and the least amount of back pressure. Now, having said that, what is the problem with back pressure?

Suppressors reduce recoil. Their internal baffle system and added weight to the end of the weapon make us have less recoil. However, on a semi-auto, because we're increasing how much gas is coming rearward, we might have a higher felt recoil because of that bolt speed due to the increased back pressure of our suppressor. So, knowing how much back pressure will give us a good idea of how much recoil and gas is where you get to the face. The other aspect is, as I mentioned, gas to the face. There's a lot of bad things inside of those gases that we want to try not to be inhaling. And with a high back pressure suppressor, especially in an indoor environment, you'll find that not only are you breathing this in, but it's tearing up your eyes and that is definitely not good for us. Finally, there's the malfunction aspect. You can over gas so much that you get what looks like a stovepipe or a forward ejection. Your brass should eject to about the three o'clock position and if you get it just right, closer to the four o'clock position. If you're gassing really hard, you'll find those spent casings will eject forward. That's one of many indications that you're over gassing. Now, this can lead to malfunctions, but at a minimum, it's definitely going to cause undue wear and tear at your weapon and gunk up the internals of your weapon much, much faster. So, again, understanding the gas back pressure and understanding when it's time to mitigate that back pressure so that you don't have undue fouling or malfunctions.

So, for our test, what we did is we took a 16-inch AR-15. That's this one you're seeing behind me. We put a Geissele rail on a couple other accessories, but the really important accessory is the rifle speed gas block. The rifle speed gas block has 12 settings of gas back pressure. What we found is that on setting 10, it's rather ideal for unsuppressed fire, meaning no suppressor attached, 10 is where we need to be. Most AR-15s are so over gassed that you can swap out a bunch of parts and the gun will continue to function. When we get our gas setting just right, if you start tinkering, you might find you need to do the test again. How do we know it's the right amount of gas? Easy. 12 is the maximum amount of gas. As we choke that gas down all the way down to position one, we're looking for last-round hold open, meaning the cycle of operation is the hammer comes forward, strikes the firing pin, the firing pin ignites an explosion as it hits the primer. Primary ignites the powder, powder pushes the bolt down the barrel, and then it unlocks because of the gases that hit the gas key. As the bolt carry goes to the rear, the bolt unlocks and begins traveling rearward, extracting and then ejecting out the ejection port. It's got to come back far enough to grab the next round, but more than that, it has to come back further to get last-round hold open. During our test, what we're looking for is last-round hold open and then the repeatability of last-round hold open, not just one time, but say three times in a row that we still get last-round hold open on said setting. If I choke the gas all the way down to setting two and I'm still getting last-round hold open, then I'll choke the gas down to setting one and look for last-round hold open again. If I'm still getting last-round hold open on setting one, that means that suppressor is a very high back pressure suppressor. As opposed to if I'm on setting seven, eight, nine or ten, that's pretty darn close to where I need to be to shoot unsuppressed, which means I'm only adding a little bit of back pressure and I continually choke it down until I don't get last-round hold open. Now, it's important to note that we actually did this on more than one day. There was the first day we did the test and we came back out and did it all over again. Some of those numbers fluctuated, but usually only by one or two settings. I'll give you the breakdown of those numbers, but in the end, we really categorized into three separate sections. There's the very low back pressure suppressors, there's the relatively high but not horrible, and then there's the very high back pressure suppressors. Now I'll break down which one these are, but I want you to know that if you're on a low back pressure suppressor, you really don't need to do a whole lot to mitigate gas. You maybe don't even need adjustable settings or to worry about any of that. In this middle section, you should probably consider some type of mitigation. There are several types out there and we'll make a video on gas mitigation or back pressure mitigation, but when you're in that middle category, you need to be thinking about it. When you're in the far end category, real high gas back pressure, I highly recommend you do something to reduce that back pressure.

Here's what we found in the results for our experiment. Remember setting 10 on one of our days was no additional back pressure, such as unsuppressed. On the second day, setting 9 was our last round hold open without a suppressor. Between 9 and 10 were our hold opens for no suppressor.

The Flow K from Huxworks, the QD from Huxworks, and the Ventum from Huxworks performed the best. The deviation between the first two and the third and fourth, let's say, is actually pretty extreme. The Flow K on day 1 was setting 10, equal to unsuppressed. Day 2 of the Flow K, setting 8 to get last round hold open. On day 2, it showed just a little bit more gas back pressure, but such a tiny amount. It's almost hard to observe. The QD, that's this suppressor, the predecessor, the older version of what's now the Flow K. Believe it or not, I like the suppressor a lot. I'll go into that in another video, but this suppressor performed very well with last round hold open on setting 8 on both days. I remember on day 1, 10, and 9 for unsuppressed. The Ventum, it was a big leap to go to the Ventum. Instead of 10s and 8s, we dropped to the 6s. The Ventum did offer a decent amount of gas back pressure, but not an insane amount. Still, a very low back pressure suppressor. It's being a 6 on a scale of 1 to 10, 10 being unsuppressed. Finally, we tested out the new Surefire RC3 on day 1, setting 5, and on day 2, setting 6.

Of low back pressure suppressors, it performed pretty well, but by comparison to the Huxworks, it did not perform pretty well. After the Surefire, we jump into the OK category of back pressure. The OK category, I'm going to summarize it as being a 4 and a 3 all the way down to a 2, which is pretty unimpressive. 4 and 3, it's not a ton of back pressure reduction, but they're lower back pressure suppressors. Now that we've gained this information about what levels of back pressure our suppressors have, if you want to know specifically what each one has in the graph, we'll show you all the numbers and break down of what we got. If you're curious as to the ammunition we used, we used PMC X-TAC 55 grain that was standard across all of the ammunition on both days.

In the end, the biggest takeaway I got is my favorite suppressors for back pressure specifically is on this side of the table. Truth be told, I'm not really in love with Surefire suppressors. In fact, I've kind of had a thing against them for a very long time. This is one of the better ones because it's low back pressure and the historic ones, as you see, are relatively high back pressure. But the Huxworks, now we know Huxworks was the pioneers of the flow through design, so it's no surprise that they performed the best. But between the two highest performing ones, both of them require Huxworks specific muzzle devices, which I'm not a big fan of proprietary. I like universal and the Ventum offers a universal mount system. So it's got that standard hub. So now I'm allowed to put my AAC or my whatever system you like. Personally, I like the SilencerCo ASR system and so you'll see I have the ASR attachment on the bottom of this. Now this suppressor can be handed out to all my weapons from 7.62 on down and I can get that reduced back pressure. So my biggest takeaway is this is one of my new favorite suppressors because of its modularity and low back pressure. I hope you enjoyed the video. I hope you gained some good insight and it will help you in your purchasing power of your next suppressor. In addition, if you don't mind, this is all my personal gear. This is our personal investments. We're putting a lot of time and energy into this and we're not gaining anything from this. We're just sharing our experiences and hoping you gain something as well. So please hit the like, subscribe, comment, all that good stuff. It takes a second. It's free. Even if you just say, "Hey, good video." That really helps us defeat the YouTube algorithm of them not liking us, talking about this kind of stuff. For reference, I call them suppressors, silencers, and cans. And if you don't like that, feel free to say something in the comments that you think I'm dumb. Anyways, have a great day. As always, stay safe.