Need to replace jig parts for your 80% project?
The drill bits and end mill bits that turn your 80% lower into a finished, precision-milled AR 15 receiver are the critical components of any 80 Lower Jig. Using dull, over-worked bits will produce a sub-par receiver that hangs triggers, sticks magazines and fails to fire consistently. Even worse, the milling process can result in some nasty injuries thanks to broken bits and flying debris.
Generally speaking, a good set of bits can finish two 80% lowers. We strongly recommend investing in an extra mill bit for your first build, just in case – after all, you’re turning raw aluminum with steel at high rates of speed. Pressure, heat and speed can result in a broken bit and a halfway-finished lower sitting in a jig.
You never want to remove your lower from the jig once you’ve started machining, so having extra bits on hand will prevent issues like this. We only sell quality, made-in-the-USA hardware. Our 80 Lower Drill Bits and end mill bits are solid carbide steel and feature 0.75” flutes for performance and precision.
You’ll also find we carry 3/8” bits, 5/32” bits, 19/64” bits and 3/8” drill stop collars – that includes everything you need to begin machining and finishing your own 80 Lower.
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