The brass colored Winchester Primers are not plated as a cost cutting measure is the only thing I can surmise from the situation.

The older silver colored ones are nickle plated.

Obviously they didn't put a warning label on the box telling you they are undersize. Take my word for it. Buy something else is what I'd do.

Google it and you'll see several things about it on reloading forums.


No government employees were harmed in the making of this mess.