Saw the following in a description of a Boland 450 NE on Cabelas web site :

"[...]double rifle nitro proofed for black."

I'm at work and don't have my references available (should be working but it's Christmas Eve after all...).

I cant' remember the history of the 450. I believe that it was originally BPE cartridge.

Does this mean that it's only proofed for 450 BPE? I'm not familiar with Belgian proof marks.

Merry Christmas.

-Steve