A friend explained to me that similar to the throat, an eroded or non uniform barrel crown will allow gases to escape more erratic when a boat tail exits the barrel vs a flat base.
He also stated that his belief is a Nosler partition can " seal" the back of the bullet / barrel interface due to the lead being exposed caudally.
I have had a barrel or three recrowned by a gunsmith and it seemed boattails grouped better. But my observations are anecdotal at best.
Last edited by Angus1895; 02/28/21.
