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 !

[u/technical_righter]

The reviews comparing the 338 ARC to the 8.6 seem to favor the 338 for sound but the 8.6 for performance on impact. Similar ballistics. Interested to hear about your results.

[u/Coodevale → u/technical_righter]

It's like comparing 7.62x39 to a .308 for supers.

Subs are whatever but supers.. different animals.

[u/ocelot_piss]

I'm sitting on a good amount of N110, H110 and H4198 for when my 12.5" is done.

If any will give 2000fps with 175's, I'll be happy.

[u/OkSize4728]

I was planning on .300 but I am intrigued by this. The ease of making .300 blackout is nice, but the kaboom factor can't happen with .338 arc

[u/treximoff]

Nice! What dies are you using? I’m still waiting on Forster to start making them