338 ARC – 300 gr HPBT – Ultramax (ULT-338ARC-1-N) – 200 Rounds

Suppressed 338 ARC shooters who want a heavy, accurate subsonic option beyond the factory Hornady loads have a new choice. This listing is Ultramax Subsonic 338 ARC 300 grain hollow point boat tail match ammo, MPN ULT-338ARC-1-N, sold as a 200 round bulk case.

The 300 grain hollow point boat tail match (HPBT) bullet is a heavy, high sectional density projectile designed for accuracy at subsonic speeds, where heavy bullets make the most of a suppressor. Ultramax loads this as a subsonic cartridge, so it stays below the speed of sound for quiet shooting. Match bullets are built for precision on paper and steel rather than controlled expansion.

The 338 ARC (Advanced Rifle Cartridge) is a newer Hornady cartridge built for the AR-15 platform and standardized by SAAMI in 2025. It fits a standard AR-15 lower with a 338 ARC barrel, a bolt and magazines made for the ARC case family. A common question is whether 338 ARC is interchangeable with 300 Blackout. It is not: the two use different cases and bullet diameters, so only fire this ammo in a firearm marked 338 ARC. The cartridge was designed around suppressor use, and Hornady offers it in both supersonic and subsonic loadings. Its .338 inch bullets range from lighter supersonic hunting loads to heavy subsonic projectiles, so one rifle can cover deer and hog hunting at moderate range as well as quiet suppressed shooting. Subsonic loads may need a suppressor or adjustable gas to cycle reliably, so confirm function in your rifle. A 200 round case covers tuning and range time.

Ultramax ULT-338ARC-1-N is new production ammunition, not reloads, made in the USA. Each cartridge uses a brass case with a boxer primer and is non-corrosive, and the boxer primed brass is reloadable for handloaders. Buying by the case also keeps you on one production lot, so point of impact and velocity stay consistent from box to box. This case comes in factory packaging as 10 boxes of 20 rounds for a total of 200 rounds of 338 ARC 300 grain Hollow Point Boat Tail Match (Subsonic).