I'm shooting a CVA Magbolt 50. The bore is .500 to .501, grooves are .508 to .509. The NE's I have are .503. If I remember right the Whites are also .503. Either way they should work in my gun.

Where do you guys get them? There is one store locally that carries the larger ones but I have never seen the 400's there. Also, what's a good price for them?

Thanks for the comments so far.