I bought a bag of 100 new Remington .221 Fireball cases about 20 years ago and about 1/3rd of the brass in the bag had split necks exactly like shown in the OP's original picture. The rest had terrible neck thickness variation (.006" on one side and could almost see through the other) and were basically unusable. Went 'round and 'round with Remington CS and never did get replacement brass.