Without a gage to measure your base to shoulder dimension before and after FL sizing, you really have no way of ascertaining that what you are doing is correct.

And if you are not keeping your brass trimmed to sami specs after FL sizing, you risk a chamber explosion from a pinched bullet.

For best brass life, listen to what the experts are saying (above) and only work your brass enough to fit YOUR chamber. Anything more just shortens brass life and possibly yours too if it fails catastrophically.