I am not afraid to use virgin brass on load testing at all anymore. Many times I have had loads shoot just as good on the first firing with quality brass as I have on sequential firings after that.
I fired the 2.73" group below with virtually no vertical using virgin ADG brass at 871 yards prone from an Atlas bipod and 4-24x Trijicon Tenmile scope. What you might find even more impressive than it being virgin brass alone is that the group was fired with virgin 300 PRC brass necked up to make rounds for my 338-375 Ruger. The other photo shows a virgin piece of 300 PRC necked up to 338 cal on the left, and next to it on the right is a Fireformed piece of 338-375R brass. You can see that the shoulder on my 338-375R blows quite a ways forward when Fireformed. I have more work to do with this load because it has not been ladder tested yet and the brass has only one firing on it, but it's looking like a good place to start.
I have also had similar results in two 300 Norma Mag Improved rifles using Lapua brass, a 20 TAC Fireformed from 223 cases, and a 7mm Mag with virgin brass.
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