PSA 8.5" 338 ARC Lightweight Hex Complete Upper

The PSA 8.5" .338 ARC Lightweight Hex upper is the cheapest complete-upper route into Hornady's .338 ARC cartridge. It drops onto any standard AR-15 lower and ships with everything the caliber needs to run: the 9310 nitride full-auto-profile bolt carrier group built around the 6.5 Grendel Type 2 (.136) bolt face, a charging handle, and a DuraMag .338 ARC 10-round magazine. Because .338 ARC feeds from C-Products DuraMag 400 Legend pattern magazines rather than 5.56 STANAGs, having a correct magazine in the box removes the most common stumbling block for a first .338 ARC build.

The barrel is 4150V chrome-moly-vanadium steel with a nitride finish and the Hornady-specified 1:8 twist, which stabilizes the heavy .338-caliber projectiles the cartridge is built around. At 8.5 inches with a pistol-length gas system, this upper is tuned for short, suppressed shooting; the 5/8x24 muzzle threads accept a .338-rated (.36-bore) suppressor and .338 ARC muzzle devices. The .338-inch bullet exceeds a .30-cal bore, so a .30-caliber can is not rated for this cartridge; pair a .338 Lapua-rated can like the SilencerCo Omega 36M. The 7-inch Lightweight Hex M-LOK free-float rail keeps weight down at the front and leaves room for a light or hand stop.

This is the value foundation for a suppressed .338 ARC pistol or SBR. Pair it with a standard AR-15 lower, add DuraMag .338 ARC magazines, and the only remaining decision is the can.