This is your ultimate AR9 pistol guide! We’re covering parts compatibility between the AR-9 and AR-15, how to pick the right parts for the perfect 9mm AR build, and we’re providing instructions on how to build an AR-9, start to finish. Let’s get started. What is the AR-9? A typical 9mm AR Pistol Kit The AR-9…
A lot of “AR-15 experts” who proudly declare their uncontested knowledge of the AR platform are about to get upset. That’s too bad, because those people are, objectively, wrong on this matter. Here’s the truth: When it comes to AR-15 bolts, there is zero meaningful difference between a 9310 bolt and a C158 bolt. Cue…
We won’t keep you waiting ’til the end: 6.5 Creedmoor offers more power and better long-range accuracy than 6.5 Grendel — but there are plenty of reasons you might still prefer 6.5 Grendel. See our detailed comparison of these two rounds to find out which one is best for you. 6.5 Grendel: What Is It?…
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…
With dozens of calibers available for it, the AR-15 has become one of the most popular rifles in America. But with so many options, picking any one cartridge can seem overwhelming — so, here are our the top picks for various tasks: All-purpose, long-range, personal defense, subsonic/suppressed fire, and more. Best All-Purpose Caliber: 5.56/.223 Specifications…
Whether it’s safe to shoot 5.56 NATO in a .223 Remington-chambered rifle has been a longstanding debate, especially in the world of AR-15s (we cover this in detail in our guide: 5.56 vs .223: What’s The Difference?). That debate can be laid to rest, now, thanks to the introduction of the .223 Wylde. What is…
There’s one question every new AR-15 owner asks when buying ammo for the first time: Can you shoot 5.56 NATO in a .223 Remington gun? And is the opposite true: Can you shoot .223 Remington in a 5.56 rifle? The most burning question of all, though, is: What are the real, verifiable differences between 5.56…
Lots of math, physics, and engineering have gone into maximizing the accuracy of modern firearms, including the rounds we chamber. Ballistic coefficient (BC) is one way of calculating the accuracy of a bullet in flight — but what, exactly, does it represent? Let’s explain. What is Ballistic Coefficient? BC measures the ability of a bullet to…
The 1911 has, since its original design over 100 years ago, remained relatively the same ever since — but there are some key differences between the gun’s original design, called the Series 70, and the updated design, known as Series 80. Let’s compare. What is a Series 70 1911? The Series 70 1911 — exampled…
Bought a 1911 slide kit? Finishing your 1911 build kit? Here’s how to assemble your slide! If you’re completing an 80% 1911 build, follow our guide on how to assemble your frame. NOTE: These instructions cover assembling a series 70 slide. Series 70 slides are what both 80% 1911s and many “mil-spec” retail 1911s use….
DISCLAIMER: If you are new to the world of DIY gun building, you likely have a lot of questions and rightfully so. It’s an area that has a lot of questions that, without the correct answers, could have some serious implications. At 80-Lower.com, we are by no means providing this content on our website to serve as legal advice or legal counsel. We encourage each and every builder to perform their own research around their respective State laws as well as educating themselves on the Federal laws. When performing your own research, please be sure that you are getting your information from a reliable source.
