I posted the suggestion that the hollow base COULD flare out like a badminton shuttlecock because I too,saw the same high speed photography Unclenick mentioned.
As Unclenick suggested,its more likely that would be observed in a .357.
If the loads are pushed to 9mm +p levels,they are in the range of .357 pressures.
I think you need to provide some evidence for this statement.
Sorry,I don't dance just because you snap your fingers. I consider the corroboration of both Unclenick and Dufus quite enough. Hollow bases are to provide seal and obturation for low pressure target loads that may not otherwise "bump up"
Knowledge of what happens to an over driven hollow base bullet has only been around since the Minie ball.
I really do not care if you believe me or not.If you want to learn something,take the lead and do your own research. Don't expect me to serve it to your satisfaction on a silver platter. I'm not worried about winning a debate or proving anything. I'm offering an insight for free.
The application for hollow base lead bullets is lower pressure target loads,and at some pressure point,skirt deformation will occur.I made no claim about what pressure that might be. Apparently ,since you seem,via your rebuttal,to be "uninformed" it was knowledge well shared.
Once again,I acknowledge there is 115 gr JACKETED 9 mm hollow base ammo.
The heavy copper jacket serves a different function and performs differently than the lead skirt on a cast or swaged hollow based bullet.
O'heir,wrong again (snicker). The pressure drops rapidly after the bullet exits.Tell me,if the pressure is sufficient to obturate the skirt outward to seal the bore,what happens when the support of the barrel steel ends suddenly,and before the pressure is lost?
For more fun thoughts,if pressure is zero immediately upon the bullet exit,how does a race gun compensator work? Folks who shoot comp guns want zero exposed lead because the bullet base lead spews and cakes up in the comp.