About seating out with straight walled cases. Most of these develope better ignition and accuracy due to better internal ballistics if the bullet is crimped, heavily. if there is no crimping groove where you want to crimp the bullet, the Lee Collet die, called the Factory Crimp Die can be used when no other die works without buckling the case. They are available for about any ctg. and Lee will make one for you, for rounds that aren't standard.