Next, milling out the magazine release slot.
Make sure to check fitment and adjust if needed.
While I had the right size endmill in there, I move over and milled the flats on the selector tabs. I dropped the selector in to check fitment.
Next up, the left hand grip panel is milled. You want to mill so that you finish 3/16 of an inch above center as the web thickness will end up being 3/8 when we are done. This finishes the left side, now for the right.
On the right side, I milled a shallow pocket for the head of the take down pin and then proceeded to mill the pocket for the mag release button. Now this operation involves milling the slot, and then, with the same 5/16 mill, mill a straight pocket down center of button pocket to accommodate the spring.
Once the pocket is milled, make sure to check fitment. You want this to move smooth and easy without hanging up.
Here I milled the right side grip panel to finish the 3/8 thickness. If done proper, it should be centered.
Here, the right side is done. I drilled the second hole for the trigger guard. Be sure not to drill too deep as it does not go all the way through. It is hard to see, but I also drilled a 5/64 inch vent hole up near the right take down pin. It is only 1/8 deep.
Next up on the list will be the buffer tube end. The hard part on that end will be drilling the hole for the pin that holds the bolt release lever in place. It is a small diameter (3/32) and needs to be long. I will make a drill guide out of a small piece of keystock to keep the drill from walking while drilling. I don't have a tap the right size, and don't intend to buy one as they are not cheap. I will drill and tap a couple holes in the forging where I will later mill the magazine pocket. This will allow me to bolt the forging to a piece of steel and I can then put it in my lathe where I can use a cutter to cut the threads for the buffer tube to fit into.