The AR-308 Router Jig - Universal AR-308/AR-10 80% Lower Receiver Jig

Universal Compatibility: The Router Jig is truly universal for all 308 80% Lower Receivers - AR-308, LR-308, AR-10. The .308 platform is not as standardized as the AR-15, especially when it comes to exterior dimensions. A lower receiver is mounted in the jig in the same manner as it will mount to an upper receiver; by the front takedown, rear takedown, and buffer support. By using these known standardized features to mount the lower, and in conjunction with our No-Touch Side Plates, we can guarantee universal fitment for any AR-308 / AR-10 lower receiver regardless of exterior dimensions or slight design variations. Many other jig designs make use of non-standardized features or rely upon clamping the lower into the jig by the sides. The result is non-universal fitment and the opportunity for out of spec finishes. By mounting the lower receiver in our jig by standardized features, an additional benefit is the most accurate finished product possible. In order to guarantee proper fitment and operation once the lower is finished, all finished features must be aligned, centered and parallel with the components for which they are designed to receive.

No-Touch Side Plates: Our industry first No-Touch Side Plates have additional channels machined into the inner surfaces to further provide ample clearance on either side of the lower receiver to accommodate .308 platform variations or oversized exterior features. This no-touch approach prevents accidental damage or marring to the side of the lower receiver during assembly, use, and disassembly. As an added bonus, the jig only contacts the jig by its mounting points, therefore the lower can be mounted or removed quickly and without entirely disassemble the jig. In most cases only 3 screws and 2 quick-release pins are all that's needed to mount or remove a .308 lower from the jig. Some .308 designs will require the user to partially loosen, but not remove, the side plates.

Centered and Parallel Features: Using the standardized features to mount and locate the lower receiver in the jig guarantees the finished fire control group pocket, trigger slot, safety selector, and trigger/hammer pins will be perfectly within tolerance. This ensures proper fitment and trouble free operation once the lower has been completed and assembled to an upper. As the sides or other dimensions of .308 platform lower receivers are not controlled or consistent, using them as a means of mounting the lower into a jig can result in an off-center fire control group pocket and trigger slot, misaligned safety selector holes, or misaligned hammer and trigger pin holes.

Optimized For Router Use: By far the most popular method for completing 80% lower receivers at home is by use of a handheld router. This is for good reason, of course, because it's the most cost-effective and readily available method, and finished results can rival those of an expensive CNC machine or mini-mill. Our Universal Router Adapter addresses certain drawbacks previously associated with using a woodworking router to mill aluminum. First, for the main milling operation, all other router jigs rely upon "tracing" an internal FCG pocket shaped template by running the end mill shank against a template surface. This method generates excessive heat, excessive wear on the template surface its self, and the end mill is not supported in all directions for the milling operation. Our Universal Router Adapter incorporates two main features which reduce or eliminate any drawbacks to utilizing a compact router for milling aluminum. First, the Adapter houses a high-speed bearing which assists in centering the Adapter to the router, and supports the end mill in all directions at all times, greatly reducing tool chatter during the entire milling operation. Second, the Adapter accepts 3 sets of Guide Pins, corresponding which each of the 3-step milling process, which are utilized to trace two external templates. The external templates with Guide Pins completely eliminates the need for an internal template coming in contact with the cutting tool.

Less Drilling: Advancements in The Router Jig's design allowed us to reduce the drilling portion of finishing the FCG pocket and trigger slot to only 2 holes! The integration of our bearing supported, fully optimized 5/16" end mill make the milling portion faster, easier and safer than ever before. Removing the bulk of material by drilling is no longer necessary because the milling portion is so fast and easy. Our end mill design and bearing support system allow the user to remove material safely at a much faster rate than with other jigs. Other jigs rely upon the drilling portion to remove the bulk of material, which is extremely time consuming and labor-intensive. Beyond that, unsupported 1/4" end mills used with other jigs are not nearly as fast and effective in removing aluminum. In fact, with some 7075-T6 forged 80% lower receivers, milling with the inadequate cutting tools offered with other jigs can be downright frustrating and painfully tedious. As an added bonus beyond the time savings, our extensive testing revealed that optimal finish quality is achieved when fewer holes are drilled. Additionally, preventing the end mill from "jumping" from one drill hole to the next reduces the opportunity for the end mill to shatter.

Oversized Hybrid End Mill:
Our Patent Pending custom reduced-shank 5/16" diameter end mill is an industry first, and an absolute game changer in the realm router based 80% lower receiver milling. We identified the end mill tool as a weak link in many existing router based jig designs, and addressed the drawbacks with a fresh outlook. Two of the limiting factors related to the end mill tool size are the router collet size, and necessary minimum length for the application. Currently, all other router based jigs utilize a 4" long, 1/4" diameter end mill which is unsupported entirely during the milling process. The result is a cutting tool much longer and narrower than what would otherwise be ideal. The effect of this is unwanted tool chatter, tool breakage, unsettling feedback, slow milling operations, and poor finish quality. Our reduced shank end mill utilizes a portion of the end mill shank which is 1/4" in diameter in the collet portion of the shank, but 5/16" for the remaining length of the tool. Our end mill is exponentially stronger and more rigid than a 1/4" diameter of similar material construction and length. Milling your 80% lower receiver is now a fast and smooth process with the 5D Tactical AR-308/AR-10 80% Lower Router Jig.

High-Visibility Milling: The 5D Tactical Universal 80% Lower Receiver Jigs utilize recessed milling templates, which are incorporated into the router support plate and therefore do not rely upon using the end mill shank for tracing an internal template. The result is a wide-open viewing area directly above the fire control group pocket. With the Jig oriented in a manner where the buffer support is closest to the user, full visibility of milling is possible for the majority of the process. Additionally, the router support plate’s viewing port is large enough to accommodate even a full-size wet/dry vacuum attachment for fast aluminum chip removal. Keeping the FCG pocket clear of chips is a major factor in guranteeing optimal finish quality.

Super Fast Assembly: The Router Jig's professionally engineered design minimizes the number of total components and screws necessary for assembly. What's more, once the Jig has been assembled, it never needs to be disassembled! Only three to six screws and two quick-release pins are required for fixing or removing a lower from the Jig.

Integrated Depth Gauge: The Router Jig's 1-2-3 finishing process is made even easier by the integrated drill and end mill depth gauge which is numbered for each corresponding step, with depth markings for each milling pass. This design allows the user to keep both hands free to adjust the router plunge depth, and secure the drill bit stop quickly with total precision. Fast and accurate drilling and milling has never been easier!