The 80% Jig Compatibility Guide
Picking the right 80% jig starts with the platform you’re building. This guide covers which jigs and tooling fit AR-15, AR-9 and LR-308 (AR-10) lowers.
AR-Type 80% Jig Compatibility
AR jigs are made for AR-pattern lowers.
AR jigs come in two sizes
AR-15 jigs are designed for 5.56/.223 lowers, which can also chamber rounds like 300 BLK. Most AR-15 jigs are also compatible with 9mm (AR9) lowers.
LR-308 jigs are designed for .308 (“AR-10”) lowers, which are physically larger than 5.56/.223 lower. The .308 lower can also chamber rounds like 6.5 Creedmoor and .243 Winchester.
Elite Builder Patriot Jig (AR-15, AR9, AR-10)
The Elite Builder Patriot Jig is compatible with all three types of 80% lowers: AR-15, AR9 and LR-308. This jig is made from aluminum and steel. Its various templates provide guidance for drilling the hammer, trigger, and safety lever pin holes, and for milling the fire control cavity to make room for a lower parts kit.
This jig fits both aluminum (billet or forged) and polymer AR-type lowers.
Optional Bits
- (1) ⅜ Drill Bit – 5”
- (1) 5/32 Drill Bit – 3”
- (1) ⅜ Short End Mill – 3”
- (1) 5/16 Short End Mill – 4”
- (1) ⅜ Long End Mill – 4”
These bits are optional, but highly recommended, and they hold up for more than one build. Replacement plates and bits are available if any wear or damage occurs.
Liberty 80% Lower (AR-15, AR9)
The Liberty AR Jig is basically a cheaper, simpler version of the Elite Builder Jig. It uses the same basic design — side plates with drill guides, and top plates with milling guides — to fabricate an AR-15 or AR9 lower. Unlike the EB Patriot, though, it cannot physically accommodate larger .308 lowers.
Optional Bits
- (1) ⅜ Drill Bit – 5”
- (1) 5/32 Drill Bit – 3”
- (1) ⅜ Short End Mill – 3”
- (1) 5/16 Short End Mill – 4”
- (1) ⅜ Long End Mill – 4”
The optional bits available for the Liberty Jig are the same as the Elite Builder Jig.
Frequent Jig Questions
Q: What jig fits a 300 BLK lower?
A: A 300 Blackout-chambered lower is merely a 5.56/.223 lower receiver. The only difference between a 300 BLK and 5.56/223 AR-15 is the barrel and gas system length.
Q: What jig works with 9mm AR lowers?
A: Any jig that works with standard 5.56/.223 lowers also works with the available 9mm (AR9) 80% lowers currently on the market.
Q: Do any jigs come with an 80% lower?
A: No. Because of recent ATF decision-making, 80% lowers and 80% frames are sold separately from jigs and tooling.
Q: What tools do I need to use my jig?
A: All AR-type jigs we sell are designed for a standard drill press.
Our Builder’s Guide compares drill press and router jigs.
Q: Are jigs considered firearms?
A: No. A jig on its own is a tool, not a firearm or firearm part under federal law.
However, some states and cities restrict jigs and jig tooling, and we don’t ship them to those locations. See our jig shipping restrictions and check your state and local laws before ordering.
