Nosler brass is made by almost every brass manufacturer, most likely cheapest bid gets the contract. They use remington, federal, and winchester for everything unless it is only made by Norma.
I was using Nosler brass a lot lately but have found many loose primer pockets out of the box, or after one firing where winchester brass didn't. Nosler brass is very uniform, well sorted by weight and chamfered, deburred, flash holes and all, it's nice but much too expensive when it doesn't last as long as the cheaper stuff.