My grandson was shooting some RORC 5.56mm L2A2 NATO ammo in his Bushmaster AR 15 yesterday when he experienced a blown primer. Did not discover the blown primer until we were policing the brass after he had finished firing.
On checking other cases fired, most had a shiny spot wiped on the head of the cases, likely from the ejector.
I haven't had much AR experience, but the older gas guns (M1 & M14) were pretty hard on brass, too, but I can't remember ejectors marking the case head. As I recall, the extractor did a number on the case rim.
The blown primer is definitely a sign of high pressure (or excessive headspace for that particular round). Does the AR usually leave the ejector mark on rounds loaded to normal pressures or should it be considered a pressure sign, as it would be in other rifles? Anyone else have any problems with the surplus RORC ammo? Either way, will not fire remaining RORC ammo.
Regards,
hps
On checking other cases fired, most had a shiny spot wiped on the head of the cases, likely from the ejector.
I haven't had much AR experience, but the older gas guns (M1 & M14) were pretty hard on brass, too, but I can't remember ejectors marking the case head. As I recall, the extractor did a number on the case rim.
The blown primer is definitely a sign of high pressure (or excessive headspace for that particular round). Does the AR usually leave the ejector mark on rounds loaded to normal pressures or should it be considered a pressure sign, as it would be in other rifles? Anyone else have any problems with the surplus RORC ammo? Either way, will not fire remaining RORC ammo.
Regards,
hps