I have been testing Lapua, IVI, and Lake City brass in my 308 SSG69 with ZFM-6x scope.
All of the loads were tested at 2550 fps. 1/2 grain fluctuation in differing brass using Varget to match the Lake city match round. All were using the Berger 175 VLD. and Varget powder. tested 20 rounds of each in 5 round groups. Lapua held the tighter groups at 200 and 300 yds and matched the IVI at 500 and 600 yds. IVI was decent at all the ranges shot at which were 200,300,500,and 600 yds. The lake city was equal to the IVI at 200-300 but was better than both the IVI and the Lapua at 500-600. Tempurature was at 34F with a 90 degree wind at 4-5 mph. Barrel was allowed to cool by fan. Strings were shot in 2 min. for each 5 rounds. Barrel cleaned after each 20 round group of brass, with 2 fowlers fired after cleaning. This allowed me to fire form for my chamber some new brass.
The Lapua annealed fairly easy, IVI takes a little longer and the Lake City takes the longest.