October 23, 2023
One of the most frustrating situations you can run into when building an AR-15 rifle is a finicky gas system. This doesn’t happen as often with 5.56/.223 guns, but it can happen to any new build. I was having trouble tuning a 6mm ARC AR-15 I had recently built, and I was growing increasingly frustrated trying to find a solution. I tried different buffer weights and springs, magazines, two different gas blocks and I stripped and rebuilt the upper twice. Still, I was getting inconsistent cycling. The solution came when I met the owner of Riflespeed, offering a unique, toolless adjustable gas block with the greatest range of adjustment you can find on the market today. The short version of this story is the rifle now runs great both suppressed and unsuppressed.
What is Riflespeed?
So, what exactly makes this adjustable gas block different from others? At a glance, you’ll see a dial on the front that’s marked one through 12. It wraps around the barrel, and you can manually turn the dial to increase or decrease the flow of gas. Adjustable gas blocks aren’t new, but this is the first one I’ve ever seen that doesn’t require a key or tool to adjust, let alone have 12 settings. The secret sauce, so to speak, is a unique plunger system that moves to regulate the gas. As the Riflespeed website says, “Need more gas? Turn it up. Need less gas? Turn it down.”
Many rifles may run fine most of the time, but once you start adding a lot of variables, you introduce more opportunity for gas problems. Changing suddenly from unsuppressed to suppressed, extreme temperature variations (especially cold), different calibers, and different bullet weights can all greatly affect how your rifle cycles. Start adding different variables like these, and your perfect rifle may find itself under- or over-gassed. With the Riflespeed gas block, you can easily fine-tune the amount of gas your rifle needs in a few seconds, essentially removing the variables that would have caused issues with your rifle. This gas block system makes even more sense once you get into rifle barrels that are less than 12 inches long.
To get started, Riflespeed needs a few details on your gun, and the website has a handy configurator to match the correct model to your needs. The Riflespeed gas system is available with the common .750 inch diameter (tested), .875 inch or .625 inch diameter. You’ll need to know your barrel length, gas system length (pistol,carbine,mid,rifle), and finally your handguard length. All of this is to find out which control knob length will work on your build. The control knob length ranges from 1.9 to 5.8 inches, and you need it to extend beyond your handguard but stay inside the muzzle. It's important to note that the Riflespeed gas system is only compatible with straight gas tubes, so be sure you get the correct-length straight gas tube with a new gas block.
Installing the Riflespeed gas block is essentially the same as a Mil-Spec model. First you pin the gas tube to the gas block with the gas tube roll pin. Unfortunately, Riflespeed hasn’t found a way to make that any easier; I only dropped that damn pin three times on this particular installation. Then you slide the gas block into position, tighten the set screws, and you’re in business. The Riflespeed gas block comes out of the box with the standard plunger installed with the control knob. However, there are 10 different plungers you can select to even greater fine-tune your rifle’s gas system, and swapping the plunger is not difficult.
My rifle build centered around an 18-inch 6mm ARC barrel From Shaw Barrels, which is one of the most underrated barrel manufacturers on the market. For a handguard, I used an Aero Precision Atlas S-One M-LOK, one of the thinnest handguards you’ll find for an AR-15. The Riflespeed gas block looks bulky, but the Atlas handguard fit without issue, so the Riflespeed gas block should be compatible with basically any AR handguard on the market. My Silencer Central Banish 30 Gold suppressor arrived not too long ago, so I finished my rifle build by installing the Banish 30 Gold quick-detach (QD) muzzlebrake.
Tuning the New Gas System
Once I had the new gas block installed, I went to the range to tune the system. Riflespeed has a set of instructions after installation to find out the best setting for your rifle. To get started, make sure the control knob is on position one, and load a one-round magazine. You shoot one round at a time until the bolt-carrier group (BCG) locks to the rear. For me, this happened on setting 11 when shooting unsuppressed. Once the BCG consistently locks to the rear, you know that the rifle is getting exactly as much gas as it needs to cycle. I repeated the process with the Banish 30 Gold suppressor, which cycled correctly on setting eight.
This is where the other plunger options come into play. While my gun is now running perfectly, I’d like the gas setting range to sit closer to the middle of the 12-setting adjustment range. You accomplish that with a different plunger so you can have a greater range of adjustment on either end of your primary settings. That way, if you run into cold weather or different bullet weights, you have more wiggle room to tune the system.
I was beginning to give up hope on getting this rifle to run properly, but now it shoots perfectly, suppressed and unsuppressed, at the flip of a switch. With factory Hornady 6mm ARC ammo and my own handloads, I’ve had zero issues, and it’s become one of the smoothest-shooting AR-15s I’ve ever shot, which is because the rifle is getting exactly as much gas as it needs.
The Riflespeed gas block does require more maintenance than a standard gas block, but it’s not much and entirely worth it. After you get done shooting, put a small drop of CLP on the base of the plunger and give the control knob a few spins. After every 1,500 rounds or so, Riflespeed suggests removing the plunger to clean any fouling or carbon buildup on the plunger, and you can use a pipe cleaner to clean the inside of the gas block. Riflespeed has complete maintenance instructions on its website along with an extensive technical guide and any other information you might need for the system.
So, what’s the catch? I’ve no doubt that this is the best AR-15 direct-impingement gas system I’ve ever used, so why not have one on every single AR? As you might’ve guessed, it’s not cheap. The Riflespeed gas block will set you back $200. That’s an expensive gas block by any standard. If you can afford to put one every rifle you own, good for you! You should, but that’s not realistic for most of us. However, I do think it’s worth it if you’re going to go all-out on one rifle. I think everyone should own at least one “ultimate” rifle, so $200 is money well spent for your go-to gun. The Riflespeed system does everything it claims to do, and Riflespeed is proud to be a 100% made-in-the-U.S.A company. Whether you’re building your ultimate AR, want to upgrade a rifle for suppressed shooting and everything in between, the Riflespeed gas block gets it done.
About the Author
Jack Oller is a U.S. Army veteran, having served in the Military Police with one deployment to the Camp VI Detention Facility in Guantanamo Bay, Cuba. He has extensive firearms training from military and civilian schools and is a passionate shotgun shooter and hunter. Jack has an English degree from Illinois State University, and he started his career in the outdoor industry as Associate Editor for Guns & Ammo magazine. After Gun & Ammo, he worked as Brand Manager for Crimson Trace and now is the Digital Editor for Firearms News.
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