who me ?
in the end as long as ur bullets are all the same they should fly the same path. crimped or not
My two cents...
Bench shooting with a bolt - do whatever you want. I crimp my semi-auto ammo because I don't want the bullet seating to change with all the slamming and hammering - no matter what. I have never had any issues with bullets moving ever, but I don't want to take a chance.
Second factor (for me) is that a Lee crimp die is like 25 bucks and there is a space for it on my progressive, so...why not.
Anyway, keep doing what works for you, but that is my reasoning.