Yes, I have..............
As the others have pointed out, usually from an overworked (reloaded) piece of brass.
They clear easily (relatively speaking, as stoppages go), as the shooter found out.
The next cartridge, after the one that separates, acts as a removal tool and gets it out as you work to remove the second-jammed cartridge.
Quote History Originally Posted By StealthyBlagga:
Yes, I’ve seen quite a few case head separations, even happened to me once or twice. Not that uncommon with reloads, and one of the best reasons to have a forward assist on your rifle. Was this a legitimate factory fresh round with virgin brass, or some kind of reloaded case?.
View Quote
No, There is no need at all to use the forward assist.
Either the second cartridge will catch it and remove it as you remove the cartridge-trying to figure out what is going on.
Or, as the brass cools and contracts, it will fall out.