The parts for the 03 and the 03A3 are supposed to be interchangeable but some of the contractor produced "end buy" or " all time buy " parts were pretty rough and would not interchange. Here is an example of a late CC bolt. Note how the bolt sleeve lock and the safety cut is made in one swipe. A cut was changed on the ejector which made them function erratically some times. Even the stamped part were supposed to be "usable on" the 03. I had a couple of bolts that did not have square locking lugs. It looked as if the bold had been chucked into a lathe and turned so that the locking lugs were round. I suspect that the contractors knew that the war was winding down, their contracts were final and they would be out of business before the parts wee needed.
FWIW
FWIW

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