Introduction to the AR-15 Platform

Introduction to the AR-15 Platform

Posted by STNGR USA on Oct 7th 2022


Hello! My name is Rick Barrett and it is my pleasure to welcome you to the STNGR Workshop, a place where we talk about everything related to firearms, from gun maintenance to gun accessories. The goal of these videos going forward is to increase our knowledge of firearms regardless of where we are, whether we are seasoned pros or for novices, looking to get into guns for the first time.

In today's video, we are going to be talking about the AR-15 - without a doubt, the most popular rifle in these United States of America. We are going to go over the history of the AR-15 and then after we're gonna break down the parts of the AR-15: the upper and the lower. We are gonna introduce the vocabulary and terminology of both the upper and the lower on the AR-15 today, so that way when we get into specific videos covering each one of these topics, we don't have to waste as much time going over the terminology, we can just get right into the good stuff and learn as much as we can about these specific parts.


History of the AR-15

Without further ado, let's talk about the history of the AR-15. When we talk about the term AR and AR-15, you're gonna get 10 different answers from 10 different people, everything from assault rifle to automatic rifle and other kinds of wacky things. In this case it's not that complicated because the AR in AR-15 simply stands for ArmaLite rifle, the company that came up with the original platform in the 1950s.

ArmaLite and Colt's Manufacturing Company

So the guys at ArmaLite came up with the platform as something they could sell to the military and to law enforcement. But ironically enough they had a lot of trouble selling the concept. So a mere nine years after they created the AR-15, ArmaLite Rifles sold it to the Colt's Manufacturing Company.

Within five years of ArmaLite selling the AR-15 platform to Colt, it would reemerge for military use as the U. S. Military would select Colt to manufacture the automatic rifle for their troops in the Vietnam War. We all know it as the M16.

ArmaLite AR-15 with flash hider and early 25-round magazine. Springfield Armory National Historic Site Archives, United States National Park Service

PFC John Henson of the 1st Battalion, 327th Infantry, 101st Airborne Division cleans his XM16E1 rifle during the Vietnam War in July 1966. Image from www.army.mil.

Colt's Semi-Automatic Version

Having proved itself in Vietnam, Colt ramped up manufacturing of a semi-automatic version that it could sell to the public and to law enforcement. This semi-automatic rifle would be marketed under the name the AR-15. Now Colt enjoyed relative exclusivity with the AR-15 and the platform until the 1970s when its patent expired.

After that, any manufacturer was free to use that ArmaLite platform, to the point where now today we have hundreds of different kinds of AR-15s available to you and me. No matter what the cosmetic differences are, know that they are all running that same initial design created by ArmaLite in the 1950s.

Complete Colt AR-15A2 rifle set with manual, 5.56 mm ammunition and magazines. Image by Steve Rainwater.

1994 Federal Assault Weapons Ban

So from the 1970s up until 1994, the AR-15 enjoyed relative popularity among the public for shooting sports for hunting and self-defense. However, all that changed with the Public Safety and Recreational Firearms Use Protection Act - you and I would know it better as the Federal Assault Weapons Ban in which the Colt AR-15 design was specifically named as a banned item. This meant that the original AR-15 platform could not be bought while the assault weapons ban was enacted.

2005 Sunset of the Ban

This ban would stay in place until 2005 when it was allowed to sunset, marking the return of the original AR-15 platform to the civilian market. With the expiration of the assault weapons ban in 2005, the American public was eager to get their hands on the original AR-15 platform again, and they did so with a vengeance. So much so that the National Shooting Sports Federation in 2019 put out numbers saying there were 17.74 million AR-15s in circulation in these United States of America and that was before some events happened in the year 2020 that made obtaining an AR-15 that much harder.


Intro to the Upper and Lower of the AR-15

So now you know a little bit about the history of the AR-15 and you've decided that you want to buy one. Let's talk a little bit about the actual parts in an AR-15. Now once again, we're not gonna go in-depth in this video in which each specific part does. What we're gonna do is we're gonna introduce the concepts so that way when we do full videos about them, you'll have an idea of where they are in relation to other parts of the AR-15 rifle.

Now the first two parts we'll talk about is the upper and the lower. If you were to look at an AR-15 it is split into, well, an upper and a lower and these two parts have multiple parts within them that make the gun function.

Image from Jason Baird

AR-15 Upper Components

The parts that are included in the upper of an AR-15 are the barrel, the gas block and gas tube, the bolt carrier group, charging handle, forward assist, rail system (or some people would call it a handguard), the ejection port cover, the upper receiver and the muzzle device.

Now don't get nervous if it seems like it's a lot. It's okay because we're gonna take our time going forward in future videos to break down each one of these parts. But at least now you have an understanding if you hear bolt carrier group or ejection port, you know it's in the upper of an AR-15.

AR-15 Lower Components

Now that we have talked about the upper receiver of an AR-15, let's talk about the lower part of the AR-15 known as the lower receiver. It is the serialized portion of the firearm but that's something we can talk about at a later time. We're talking about the internals of a lower receiver on an AR-15, which includes the following parts: the trigger group, the lower parts kit, the buffer tube, the buttstock, and grips.

Once again, an overall look at the inner workings of a lower receiver on an AR-15, which we will get into in later videos.


Final Thoughts

So that's it for our first episode from The STNGR Workshop, my name is Rick Barrett. I hope you enjoyed this video and I'll talk to you soon.


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