As this is a single shot rifle crimping is a moot point unless there is some deviation in the neck tension when seating the bullets and I would be greatly surprised to see this in Lapua brass . The primary reason for crimping is to reduce any potential bullet seating shift due to recoil on bullets stored in the magazine of a firearm. Single shot equals no magazine. Another good place to use crimp is where bullets need to be seated long in a case where freebore vs bullet setback has become an issue. It helps to replace the neck tension lost due to less bullet contact in the case neck and will tend to create a more uniform "starting pressure" when ignition of the powder breaks the bullet free from the case. I use factory crimp dies on all my repeaters and taper crimp on my .223 bolt gun tack driver.