This is how I used this Jig to turn a 80 percent lower into a working firearm.
http://www.modulusarms.com/Modulus-Arms-heavy-duty-universal-ar-15-80-lower-receiver-jig/
I started by Drilling out the Trigger Hole all the way thru the receiver into the trigger area.
I used this as my point to insert my Router to mill out the lower without drilling out the rest of the holes (I think I should have drilled all the holes so I had less Material to Router out).
What lower looks like when done drilling the one trigger hole (rest will be routed out later).
What the Depth Gauge looks like when using it.
You have 3 Areas (A: Trigger Hole, B: Rear Shelf, C: Fire Control Pocket).
Also the depth Gauge Refers to the depth you will drill the Lower Fire control Pocket with the drill Jig installed (each hole is labeled A, B, C according to depth needed to finish Pocket. Ref Top Picture).
What it looks like when working on Trigger hole One pass at a time.
What Rear Shelf looks like as you Route it out with increasing depths.
What Fire Control pocket looks like as you route it out, you just keep increasing the depth till done.
What Pocket Looks like when Done, But of course leave it in the jig till you drill trigger pin holes and the safety selector hole.
Drill These holes out after you are done with pocket.
Drill from each side not all the way through from one side to the other.
And when completed with drilling and Router work this is what it looks like:
http://www.modulusarms.com/Modulus-Arms-heavy-duty-universal-ar-15-80-lower-receiver-jig/
I started by Drilling out the Trigger Hole all the way thru the receiver into the trigger area.
I used this as my point to insert my Router to mill out the lower without drilling out the rest of the holes (I think I should have drilled all the holes so I had less Material to Router out).
What lower looks like when done drilling the one trigger hole (rest will be routed out later).
What the Depth Gauge looks like when using it.
You have 3 Areas (A: Trigger Hole, B: Rear Shelf, C: Fire Control Pocket).
Also the depth Gauge Refers to the depth you will drill the Lower Fire control Pocket with the drill Jig installed (each hole is labeled A, B, C according to depth needed to finish Pocket. Ref Top Picture).
What it looks like when working on Trigger hole One pass at a time.
What Rear Shelf looks like as you Route it out with increasing depths.
What Fire Control pocket looks like as you route it out, you just keep increasing the depth till done.
What Pocket Looks like when Done, But of course leave it in the jig till you drill trigger pin holes and the safety selector hole.
Drill These holes out after you are done with pocket.
Drill from each side not all the way through from one side to the other.
And when completed with drilling and Router work this is what it looks like:
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