6.5-284 Winchester

[gdc23]

I have a custom 6.5-284 Wichester rifle built approx 35 years ago, I have always used 284 Win brass necked down and have been told I cannot use 6.5-284 Norma brass due to the measurement just above the extractor groove being increased .005 on the Norma SAMMI spec preventing this brass from use in older 6.5-284 Winchester chambers. Lately I have seen many people talking about necking up 6.5-284 Lapua brass to use in their 284 Winchester rifles. Are these rifles bored to a larger Norma spec as it seems they would run into the same issue I would with my Winchester chamber. Why coulnt Norma just keep it the same, Bad enough they are stealing the naming rights for something they originally had no hand in. Any info is appreciated.

Thanks
gdc

 

[TaperPin]

I hadn’t heard of a change to the .500” maximum diameter of brass, and current SAAMI specs still show the maximum diameter of .500” still. Any idea what this new brass is actually measuring? Any idea what your custom chamber measures at the head? It made me curious so I checked my 6.5-284 barrel that was taken off a 10 year old Palma rifle and it is a little smaller than SAAMI, but not much.

Brass is often much smaller than the SAAMI maximum, so I wonder if Norma simply upsized their brass for a little less slop?