In case you’re planning on building an AR-15 or some other AR platform at home using parts kits, a jig kit, and a lower receiver blank, then you can save a lot of time by getting upper and lower kits instead of buying the parts piecemeal.
Here’s the thing: not all AR15 upper kits come with all of the parts you need to complete a functioning rifle. Nor do all lower parts kits, for that matter.
At a minimum, here are the parts your AR-15 upper parts kit should come with, whether they’re assembled or not. (Note, some come with all of them and are assembled, and are known as assembled complete upper receivers).
● Upper receiver (sometimes referred to as a stripped upper if not a part of a kit): This is the component that will accept the BCG as well as all of the other parts of the upper assembly.
● Barrel: Barrels are caliber specific and come in a variety of lengths. Make sure the barrel you choose is compatible with your cartridge and the rest of the parts of your build kit if it did not come with them. Two of the main finishes offered in AR-15 barrels are stainless steel and chrome-moly-vanadium.
● Handguard: The handguard gives you a place to grip the rifle (since most sporting rifles lack forends) while also serving as a place to mount accessories. Two of the most popular options are Pic rail handguards and M-LOK handguards.
● Gas system (gas block and gas tube): Choosing the proper gas system is vital to ensuring that your rifle cycles smoothly and effectively. If you buy the block and tube separately, make sure that the tube is the right length for your barrel and the block is the right size for your gas journal.
● Muzzle device: Muzzle devices like brakes and flash suppressors are not always included with AR-15 upper parts kits, but if they are you may not need to buy an extra; pay close attention to the list of parts.
● Charging handle: The charging handle assists in the manual cycling of the rifle. Not all upper parts kits come with them. If you see “No CH,” you’ll need to buy a compatible charging handle and install it yourself.
● Bolt carrier group: This is another part that does not come with all AR-15 upper parts kits. If you see “No BCG,” you’ll need to get your own. Mil-spec BCGs are phosphate coated for corrosion and wear resistance, but there are many other alternatives with high-tech coatings that are harder, tougher, more corrosion-resistant, and offer better permanent dry lubricity.
● Forward assist: The forward assist, like the CH, assists in manually cycling the action. Specifically, it can be hit to ensure that the bolt is fully forward and locked. Upper parts kits often do not come with these; however, they are affordable and straightforward to install.
● Ejection port door/dust cover: Another part that often does not come with upper parts kits, the ejection port door allows spent brass to exit the rifle’s action while serving to provide a reasonable level of ingress protection against sand, dust, and other external debris.
This is just a list of what often comes with AR-15 upper parts kits. Remember that this is not all you’ll need to complete a finished rifle. You will also need a lower parts kit, a receiver blank, a jig kit, and any other parts that did not come with the parts kit. (For example, many parts kits do not contain trigger assemblies, pistol grips, or magazines).
Where Can I get AR15 Upper Kits
Looking for high-quality AR15 upper kits (as well as complete rifle kits, lower parts kits and associated hardware and accessories) that you can use to create your own sporting rifle at home? Visit SARCO, Inc., at SarcoInc.com.
Their collection is huge and contains many hard-to-find parts and accessories, so even if your aim is a maintenance project and not a build project, they can help. Visit their online store and give them a call at 610-250-3960 if you have any questions.