For those of you looking at a project to add a new AR to the safe, if you’re going to build it, you have two basic options. Build with all the parts, piecemeal (or with a build kit), or get a lower, lower parts kit, and an assembled upper, rather than piecing it all together. There are advantages to both avenues, but in this post we will look at the reasons you might want to consider an assembled upper for the build.
Save Time and Maybe Money
The most obvious reason to start with an assembled upper, regardless of whether you’re building a full-size rifle, a carbine, an ARP or even an SBR is that you can save a lot of time doing so. With a few takedown pins you can mate a complete upper with a complete lower and have a functioning rifle.
Also, it can potentially save you money too, as when kits are bundled (as in the case of an assembled upper) there are usually some savings that go along with it as well.
You Can Still Customize
Don’t think that just because you choose an assembled upper for the build, that you need to compromise on customizations. It won’t be quite as flexible as if you bought all the parts separately, but you can still more or less add or swap in any part you want, like a muzzle device or an AR-15 bolt carrier group.
Also, if you do happen to upgrade any parts, you can hang onto the original part you swapped out so you’ll always have a spare in the event you need to make a quick replacement.
You Just Want to Get the Job Done
There are some people that thoroughly enjoy working with their hands, and who take pride in the craft of their work. Not everyone is like this, and if your goal is literally just to get a rifle built so you can start shooting, then the extra time it would take to assemble a rifle with AR upper parts or with an upper kit is just not worth it. Get an assembled upper and run with it.
Also, this is a good option if you want multiple-caliber flexibility, as you can mate some lower receivers with different uppers and one platform can be used for more than one chambering.
If You’re Not Familiar with Firearm Mechanics This Is the Way to Go
Anyone not familiar with firearm mechanics would probably do best to start with an assembled upper as it can be very confusing how all the parts work together, especially for the uninitiated. You can second this opinion if this is the first rifle or ARP you’ll be building or assembling and an AR-15 assembled upper only makes even more sense.
Sheer Convenience; They’re Plug and Play Solutions
No matter how you look at it, and whether or not you fundamentally understand how an AR platform works, an assembled upper is a far more convenient option than a bunch of upper and lower parts, or even a build kit.
The other thing is that it’s just less work. You can pair an upper up with a compatible lower and the project is basically done. It takes more time and effort and therefore it’s less convenient to assemble all the parts and hardware when you’re working on a rifle, making a complete assembled upper the far more convenient of the two options. The only thing that could be easier is buying a complete, finished rifle.
You’ll Have Enough Work to Do with the Lower
Lastly, if you’re going this route, you’ll have enough work to do on the lower, whether or not you start with a lower blank. Assembled lowers are not sold generally since they require an FFL transfer. Therefore, you will either need to mill out the slots for the fire controls and trigger on an 80% lower, or you will need to buy a finished lower (which requires an FFL transfer) along with a lower parts kit and put that together.
In either case, that comes out to more time spent on the lower than on the upper, so if you need to save time somewhere, one of the best options at your disposal is to get an assembled upper and start with that.
Shop Assembled Uppers Here
Ready to start your next project? Even if you’re not sure what size upper you’re looking for, what chambering you want to build around, or whether you want to go with traditional direct gas impingement or something else like blowback that will shorten and lighten the upper, we have options. Check out our collection of complete, assembled uppers and other AR parts (including AR15 build kits) and if you have any questions about compatibility before you buy, let us know.