“Doughnuts” have little to no effect on accuracy if you have a chamber that allows the pressure ring on the bullet to be seat above the neck should junction. ( where the “doughnuts” live )If you do have chamber that will allow this, it’s hit or miss that the loaded round will still fit in the magazine. ( assuming you handload )
It’s only a couple or so of the latest cartridge designs that take “doughnuts” into consideration. 300prc comes to mind.
