Willfire MFG Division Ambidextrous M16 Drilling Jig
The Willfire MFG Division (WMD) Ambidextrous M16 Drilling Jig is made for properly locating the 1/8″ sear pin “third” hole for a full-auto sear in an AR-15 style lower receiver. Once located, the third hole can be drilled utilizing the hardened steel drill bushing. The rugged design allows the use of the jig for years to come without any issues with tolerance. The locating pins in the jig are made to exact tolerances for proper fitment in your lower receiver, reaming the rear take down pin hole to .250 and the safety selector hole to .375 will ensure an accurate placement of the 3rd hole.
*Note: These jigs are precision locating tools. If the locator pin holes are not reamed, the jig WILL require extra force (e.g. a rubber mallet) to fully seat against the side of the lower receiver. Once the hole has been drilled, a 1/4″ brass punch may be required to remove the jig. Each jig is hand-tested to fit in a standard Mil-Spec lower receiver.
The ambidextrous design of this jig allows the user to confidently drill the 1/8″ third hole on each side of the lower receiver without requiring a mill or drill press, while still achieving a straight hole through the lower.
