H4831sc, Norma brass, Win Mag Primers, 168gr Berger .284 Target
 89F

(3shot avg)
53gr = 2782 fps
54gr= 2833
55gr = 2852
56gr = 2940
57gr = 2981
58gr = 3003 (nearing max, cases sticking)

2.428" lands contact.
2.400" oal using Hornady Comparator.
27" Barrel

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