Not so. You pretty much need a 'M' dies to make cast load with bottle necked rifle brass. I have some brass that have been reloaded 10x or more for cast loads and haven't worn out yet. The bell on the neck is very tiny- only about .002" or less and keeps the case mouth from scraping the bullet- the case neck expands and contracts much more than this every time its fired and resized.

Another neat benifit of the 'M' die is that you can use it for jacketed bulelts as well, I go an extra step and remove the expander ball when I resize, use a universal decapper to punch the primer out, and use the 'M' die to expand the neck back out. It makes the case necks straighter and works the brass even less than if you simply FL resized with the expander ball in place.

The 'M' die is pretty much unknown to most people unless they have reloaded lead rifle bullets, but its worth its weight in gold.