Being in the firearms industry, we use a variety of terms. We realize many people don’t know what they mean. Since we are all about education here, it makes sense to explore some of these terms. In the future if you find yourself confused, bookmark this page and come back to it to better understand it.
Mil Spec - One thing to understand is that it is more or less a term that cannot and does not apply to any civilian rifle. In the most-strict definitions, a civilian AR 15 cannot be Mil Spec for numerous reasons. So when the term is used and applied to a civilian rifle or AR lower receiver it is not literal.
With civilian rifles, it is used to describe parts that are built as close as possible to military specifications. Technically they aren’t Mil Spec rifles, but they are built to the same standard material wise. Our AR lower receivers are 7075 aluminum, which is the same material used to build military receivers. The biggest difference is surrounding the lower receiver. Primarily, the military's ARs have the ability to go fully automatic. Since our build kits and lower receivers are not built for military use, they are not fully automatic. They are built as tough and durable though!
Billet - Billet receivers are unique and pretty cool. A billet receiver is an AR 15 lower receiver than is manufactured from a hunk of billeted aluminum. A billet receiver is a one piece lower that features unique lines and clean cuts. A billet lower doesn’t offer any advantages outside of aesthetic value. If you want something a little different from the standard forged receiver go with billet.
Forged - Forged receivers are the most traditional type of receiver. A forged receiver has been hammered into the shape of an AR lower receiver and then cut into its final shape by a CNC machine. Forged lower receivers are stronger than billet lowers and are also often more affordable. Forged lowers are also closer to being Mil Spec, in the civilian use of the term of course.
Raw - A raw receiver is an interesting concept. Raw lower receivers are for builders who want to take it a step up in their build process. A raw receiver is a receiver that is not finished and can have a finish applied by the end user. The advantages of a raw receiver are that you can choose and even apply your own finish to the lower much easier than the other options.
Fire/Safe Markings - The Fire/Safe Markings are stamped into marked AR Lower Receiver. The fire and safe markings correspond to where the safety selector will lay. A lot of 80 lower receivers do not feature these markings, but many of ours do. You can choose to order either. These simple markings are a must have for beginners who need a little reminder of where safe and fire are.
Anodized - Anodized receivers are receivers that have already have a finish on them. Anodizing is a type of finish that uses an electrochemical process to coat the lower or other parts with a tough finish that protects the aluminum of the receiver. Anodizing is the process used by the United States military.
Hopefully, we’ve cleared up some of these terms for you. If you are still confused, feel free to contact us with your questions. Now that you know the terminology, check our AR Lower Receivers here: https://www.ar-15lowerreceivers.com/collections/80-lower.DISCLAIMER: If you are new to the world of DIY AR-15 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. 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.