Sellier and Bellot brass
 

I have some Sellier and Bellot the flash hole is to small for
my decapping pin? Can these be used, or should I toss them?

Welcome aboard.
The first question I have is , are you sure it`s Boxer primed? or is it Berdan? If you can de prime it it will work. I would suggest that you use a small drill bit to open the touch hole.

What is the differnce in the two?

All the S&B brass I have ever seen is Boxer primed. And I have had the same problem as you mention. Opening the hole up a few thou is easy enough to do.

Boxer primed cases have a single flash hole in the middle of the primer pocket, and can easily be reloaded.

Berdan primed cases have two flash holes on either side of the center of the pocket. They are almost impossible to reload.

The peculiar thing is, Berdan was an American, and his system is used primarily in Europe, and Boxer was a European, whose system is used primarily in the US.

From memory, the flash hole is a "number" sized drill and is .080-.081" in diameter. Die hard benchrest reloaders have been known to "uniform" flash holes to next larger size, which is only a couple thousandths larger. You might check out a benchrest site to confirm this if you have a large enough quantity to make it worth while.

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