When I first got into 1,000 yard F Class Competition 16 years ago, word went out from Highpower Rifle and Palma World Champion David Tubb that the Russian primers produced the lowest ES and SD numbers, and he bought 700,000 of them. At that time the primers were only imported by a guy in Phoenix, Arizona and came in a rather plain box with "NON-CORROSIVE, PRIMERS, Large Rifle, and KVB - 7 on them. I bought 5,000 of them and used them exclusively for competition. Eventually the Russian factory that produced them got contracts with PMC, Wolf, and Tula. They are indeed excellent primers.
Don