Kutter:
As I'm sure you know, all manufactured goods vary a bit in specs from one "lot" to another. Generally, this variance is not important. It's just the price we pay for getting zillions of something at a cheap price.
However, I just measured some Fiocchi 209 primers v. some Winchester 209s in my shop. The Fiocchis came out to .249 wide just under the flange. The Winchesters came out to .249 just under the flange. No hull in the world would know the difference.
I will admit that Winchesters have a stepped construction with a smaller cup diameter toward the flash hole. But this is undoubtedly for "feed" purposes during automated insertion in ammunition manufacture.
Finally, I've reloaded Fiocchi primed/fired cases with Winchester primers again, and nothing falls out. Win 209s fit fine.
Perhaps Fioccchi at least has refined their specs to match Winchester -- or I have an oddly compliant bunch of imported primers.
