I heard an interesting rumor. The claim was that the .308 Larue rifles have feeding issues with PMags due to out of spec magwells and that is why you need to use the Larue mags.
I talked to Shawn about this, asking if the issues he saw with several Larue rifles might have been caused by that. The issue Shawn saw was failures to extract, and they were using the Larue mags, so I don’t think that is related.
But weirdly enough, when I had a Larue Ultimate Upper on a Larue lower, I did have some odd feeding issues. I thought maybe the gun needed a break in.
Later, when I ran the Larue upper on the Knights Armament Lower, I had no functioning issues.
So I can’t say if this is true or not, but I think it is worth sharing.