The importance of the AR-15’s gas port is often overlooked. When there’s talk about gas systems and tuning a rifle, the conversation usually focuses on gas blocks, buffers, and gas tubes. There’s little mention of gas port size. Maybe you’re building an AR-15 from an 80% lower, and need to verify you’ve got the right…
Does your AR feel a bit too punchy in the shoulder? Are you pulling your bolt after a modest range day, only to find it’s caked in carbon fouling? Getting a little too much heat in your face when you run a suppressor? These are all symptoms of the likelihood that your AR-15’s over-gassed. There…
We covered how the AR-15’s gas tube length affects dwell time, which can also cause the rifle or pistol to be over-gassed or under-gassed. Is your AR short-stroking or, inversely, producing excess felt recoil and throwing spent brass 30 feet across the range’s lanes? This is easy to diagnose. Let’s review. What is “Over-/Under-Gassed”? The…
If you were looking up how to build an AR-15 upper, or how to install a new gas block, you might’ve come across this topic: Does your AR-15 barrel need dimples for the gas block’s set screws? What is dimpling, anyway? Let’s cover it. What Are AR-15 Barrel Dimples? Barrel dimples are small indentations made…
You’ve probably heard or saw discussions about why the relationship between the AR-15’s gas length and barrel length — which determines dwell time — matters so much. But what even is dwell time? Let’s cover it, and why it matters for the sake of your rifle’s reliability. What is Dwell Time? Dwell time measures the…
This next section of our Master Guide to AR-15 Parts for builders dives into the components and functions of the AR-15’s gas system. Learn the differences between direct-impingement and piston-driven systems and all the important stuff you need to know for your build: Gas tube lengths, gas block diameters and types, and what setup you…
