Many shooters build their AR-15s at home to save on costs. By putting in the work yourself, you're saving cash on labor. You're also avoiding all the gun store fees and marked-up prices that come with buying a firearm over-the-counter. The affordable alternative involves the 80% lower and an 80 lower jig.
If you're reading this, you've probably got a good idea about how this process works. The jig completes the lower, turning it into a stripped AR-15 receiver - a firearm. So, what's the most affordable 80 lower jig you can grab in 2019? We broken them down by category: Single-caliber, multi-platform, and polymer.
Let's take a look!
Most affordable AR-15 jig
If you're like most builders, you probably want to put together a classic AR-15, and nothing more. That's great! That's how we got started. Even though it's the oldest and simplest jig, the 80% Lower Easy Jig is the cheapest jig you'll find for 5.56- and .223-chambered 80 percent lowers.
This is the 80 lower jig that started it all a couple years ago. It's also the only jig you'll find for under $200 that can complete typical billet and forged aluminum lowers, making it a great choice for a classic black rifle build.
- Completes a lower in 30 minutes to 1 hour
- Capable of completing 20+ lowers with tooling
- Built-in drill depth guides do the measuring for you
- Each plate is individually replaceable in case of mistakes
- Does not require a drill press - you can use a hand drill
- Includes written and video instructions
- Includes bits/tooling
The 80% Lower Easy Jig is so simple because you'll be drilling numerous pilot holes before you machine the fire control group (the cavity where you install your trigger and parts kit). If you're a builder who likes to go slower and take your time, this is the jig for you. The video instructions are tailored to first-timers, so there's no guess-work or scratching your head. Because this jig is set up for only AR-15 lowers, there are fewer parts and instructions you need to sift through.
Because the Easy Jig requires more pilot holes to be drilled than other jigs, overall machining time is a little longer. You also can't use this 80 lower jig to machine other lowers (like AR9 and LR-308). This jig doesn't include a hardened steel drill bit stabilizer (which makes drilling quicker and simpler), but the provided top plate is reinforced to prevent mistakes and poorly aligned holes.
Cheapest multi-platform jig
If you want to keep things affordable but you don't want to sacrifice future build opportunities, investing in a multi-platform 80 lower jig is the best choice. The cheapest multi-platform jig currently on the market is the Easy Jig Gen 2 Multi-Platform.
Easy Jig likes to keep things affordable, and that's the case here. The multi-platform Gen 2 Easy Jig is a step up from its less expensive sibling, and it allows you to complete any billet or forged AR-15, AR9, or LR-308 80 percent lower.
- Completes a lower in 30 minutes or less
- Compatible with AR-15, AR8, and LR-308
- Requires just one pilot hole before milling
- Requires no disassembly to remove lower
- Swaps between lowers/calibers in a few seconds
- Does not require a drill press (just a hand drill)
- Includes hardened steel drill stabilizer
- No-touch side plates prevent tool-on-jig contact
The Easy Jig Gen 2 Multi-Platform works quicker because you only need to drill one pilot hole. You'll be doing more milling with the provided end mill bit instead. Even though milling is more involved than drilling, the included no-touch side plates make it easy. You don't need to calculate or measure anything - the jig does the work for you. All you need to do is keep your drill and router stable while they drill and cut. The included guide plates will guide your router along until the fire control group is completely machined.
The Easy Jig Gen 2 is more capable than the 80% Lower Easy Jig, but it requires more setup. You must also ensure you're using the correct side plates and attachments, though the provided instructions spell everything else quite clearly.
Cheapest lower-and-jig combo
Most 80 lower jig options ship by themselves, no lower included. That's because most lowers are compatible with certain jig configurations, and multi-platform jigs can serve a multitude of calibers. Nonetheless, savvy builders looking for the absolute cheapest 80 lower jig will be happy to know there is, in fact, a sub-$100 combo kit available for AR-15 builds: The Polymer 80% lower and jig.
We're talking about the G150 Phoenix, a relatively new polymer lower that includes its own jig. The G150 isn't just a gimmick. Weighing in at around 0.3 pounds, this is perhaps the lightest lower receiver you can throw on a black rifle. With a lower parts kit installed, total weigh reduction comes out to around 50%. And for being ultra-light, this lower isn't cheap in quality. Engineers test-fired this lower and reinforced it by roughly 15% even though it passed initial testing. It's also compatible with all 80 lower jigs and regular AR-15 parts.
- Completes included lower in less than 1 hour
- Lower made of a composite solid-core design
- Features reinforced buffer tube housing
- Stiffened mag well and integrated trigger guard
- Compatible with all 80 lower jigs
- Compatible with all AR-15 parts
- Includes its own jig
Machining polymer is incredibly easy - obviously, more so than metal. If you're concerned that you can't build an AR-15 from scratch because machining might be too difficult, a polymer 80% lower will eliminate those concerns. Completing the polymer lower using the provided jig should take less than one hour. Since you're working with polymer, you can even use hand tools (including a hand drill) to complete the lower. Final cutting and finishing can even be accomplished with hand files.
Because the included jig is also made of polymer, chances are it'll be sacrificed during your build. Nonetheless, this kit's so affordable that ruining the jig while machining shouldn't be a concern. Polymer is also easier to machine than billet or forged aluminum, so it's easier to make mistakes with this lower and jig if you rush. Take just a little extra time to make sure your tooling isn't removing too much material while you work.