It sounds very much like what you described to be an out of round drum. If you have an auto parts store locally that can turn drums have them set them up and check the runout. Generally if it is that far out even turning it probably wouldn't work. Plus it shouldn't be necessary to turn a new drum. Since it's new, the supplier should replace it.
Fred


1956 3100 Pickup/Red/350/3sp OD/PS/Disc Brakes
1957 Bel Air Sport Coupe/Red/355/TH350/PS/Disc Brakes
2017 Silverado LT Single Cab SB/Black/5.3/6 Speed Trans
1947 Willys CJ2A w/F-Head engine