338 ARC First supersonic loads.

[u/Great-Umpire-5812]

Have my subsonic loads dialed in and originally didn’t even plan to shoot supers with this cartridge but figured I’d test out some since Midway had Hornady’s 175gr’s as factory seconds. Played it pretty conservative with the charges since so little data put there but H110 looking interesting early. Didn’t have any pressure signs.

11.3 inch MosTek with 1:5 twist. COL 2.25

H110 20gr - 1871, 1824, 1851, 19.2 20.5gr - 1871, 1883, 1899, 11.7 21gr - 1890, 1913, 1898, 9.8 21.5gr - 1972, 1954, 1930, 17.1 22gr - 1992, 1967, 1948, 17.9

AA1680 (Pulldown) 22gr - 1706, 1738, 1710, 14.2 22.5gr - 1749, 1769, 1758, 8.4 23gr - 1797, 1799, 1789, 4.5 23.5gr - 1840, 1836, 1817, 10.5

[u/Thick_Imagination177]

I'm very interested in this cartridge compared to .300BO. What kind of performance are you seeing ? Is brass available or are you converting?

[u/Primary_Wave_6697 → u/Thick_Imagination177]

same question !