another interesting M1 receiver from WW2 production

[RCS]

Here are some photos of a Springfield 1.5 mil rifle with original S-A 4-43 barrel. Everything looks normal until you view the receiver tang. Seems like something was just a little of correct alignment - or was it one of those 1943 receivers set aside because the firing pin pocket was too deep (Bob Seijas GCA Article). These were repaired after being set aside.

I think it was machining operation of the raw forging or perhaps the forging itself was not correct.

[browningautorifle]

Neat to find eccentricities... We don't see those here.

[Woodsy]

It was probably caused by a small piece of swarf in the holding jig which prevented the part being clamped in the correct position. Perhaps by a tired operator at the end of a long shift.

[jesse_]

Is the only issue here that cut around the outside of the heel?
looking at the flat edge on the side, was the cut done with a horizontal milling cutter with the heel sticking up towards the center of the milling arbor?

Also, whats up with the "pitting" on the underside? is it old corrosion or welding?

[RCS]

There is still a 50% chance that the firing pin pocket was cut too deep and later repaired by welding and milling to salvage this receiver.

The photo posted by Jesse is not what a normal receiver should look like underneath

Best answer is to have an x-ray which I have considered - just not that easy

[fjruple]

Is the only issue here that cut around the outside of the heel?
looking at the flat edge on the side, was the cut done with a horizontal milling cutter with the heel sticking up towards the center of the milling arbor?

Also, whats up with the "pitting" on the underside? is it old corrosion or welding? Attachment 126961

Jesse-

It looks like chatter from the milling reamer where a piece of steel filing got stuck into the cutting edge of the reamer.

[RCS]

That outside tang contour is not right

Some extra work was done on this receiver ?