...I knew nothing about these bullets , so I went and read thier site. Less than 10min max time. The lead bullets are placed in a bath and plated using electric current. The time in the bath controls the thickness of the plating.
They make different bullets , but mainly pistol and rifle types. The pistol ones are made for a max of about 1200 fps , not for magnum loads. In the rifle section is listed the 30 carbine , it says there on THAT page a max of 1950 fps. Maybe they make the core a little more undersized than pistols and leave them in the bath longer to bring them up to spec. with a thicker-than-pistol plate on them.
Does not sound like rocket science to me.
Chris