Flash hole too small?

US manufacturers generally punch the flash hole, they don't drill it. It's why all those flash hole uniformer tools exist to remove burrs. Off center flash holes aren't new. I've got enough examples of the products of military ammo plants to know that one of the plants, (TW head stamp), needs (needed?) to selectively reduce the workforce in the tool & die shop. Or maybe in the machine setup group.
 
A drill size of .080” was mentioned. I had .0775” and .0925” available, so I went with the smaller bit after checking that it fit rather loosely in the flash holes of the brass I decapped with the standard diameter pin.

That'll work.

The SAAMI spec. for rifle cases using the large primer is 0.078" - 0.082"

Small primer pocket rifle and pistol cases use a smaller flash hole size of .074" - .078"

European CIP brass use 1.6mm - 1.7mm flash holes.

The Lyman Flash Hole Uniformer tool cuts a .080" dia. flash hole.

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