If you have a micrometer measure the diameter of the case .200" up from case rim.
It should measure .471-.473". Measure in two orientations to see if fired case is egg shaped.
What is diameter of case neck on fired case? Should be around .344.
Also measure case at shoulder and two dimensions and see if it is egg shaped there.
Ammo has a NATO symbol so case specs should be in spec.
Fire US commercial ammo and see what happens.
If you run fired case in FL sizing die will it go back in? I suspect the ammo is Berdan primer so remove decap rod before sizing case.
If it happens with US made commercial 308 call Remington Product Service in North Carolina and give them the details and email them the you tube link. Chances are good when you send rifle in they will send you a new barreled action with differen serial number.
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