Don't really know what that rule is supposed to accomplish, other than track who's buying what and how much. I shoot some calibers which are not typically carried and/or custom loaded - so I have it shipped to the local FFL. I see it as just another move to make it more difficult for those of us who shoot/hunt by those who feel we shouldn't do either.
Here's a picture of one of the not-common calibers: Hankins Custom 220 Swift, Brux Heavy Barrel - 1/9 - 26", Stiller Action, Jewel Trigger, Shehane Stock, Nightforce 8 - 32 x 56. She's heavy, bench-rest only, but it will send a 69 grain boat-tail down range in excess of 4000FPS.
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