Does seating a projectile change brass?

[Stix]

I prefer it shallow, though i guess you could cut the specimen jar down....

Mine is an old air rifle pellet tin from another lifetime when i could see out of my eyes well enough to shoot...

I like the shot just deep enough to do a neck, no more...
204 case for comparison...

2019-04-30 19.57.42.jpg (449.64 KiB) Viewed 4047 times

[Apollo]

It doesn't take much practise to work out how far to "Dip Your Wick"...