Question on Federal Match 22 rim fire cartridges

[RCS]

I found this "new" box of Federal Match 22 rim fire cartridges that I purchased around 1999 ?

My question - why is there a center hole in each rim fire cartridge ?

They were expensive back then - over $7.00 US

[browningautorifle]

why is there a center hole in each rim fire cartridge ?

The theory was, that dimple was to distribute the primer compound more effectively. Others used the spun method of primer distribution. The Russians apparently tried the same method but it's unclear as to how WELL the idea actually worked. More effort means more expense and regardless, it was dropped.

[painter777]

They were expensive back then - over $7.00 US

1999...... And they were on Sale?

[RCS]

The Russians invented the idea of a dimple in the center of the rim fire to improve ignition and Federal paid the Russians .

Obvious that this dimple idea did not work out as it would still be around