338 ARC vs 300 PRC head-to-head: ballistics, platform, recoil, and real-world use cases for big-bore builds. This guide breaks the topic down in plain language so you can make a confident decision for your build.
The 338 ARC and 300 PRC are both big-bore cartridges built for serious work at distance, but they live in completely different platforms and serve different purposes. One runs in an AR-15 frame. The other is a purpose-built precision rifle round. The right choice depends on your platform, your range, and your bullet.
What Each Cartridge Is
338 ARC. Hornady introduced it in 2023 with one goal: push .338-caliber bullets out of a standard AR-15 lower. The case traces its lineage to the 6.5 Grendel family, sized to feed reliably through a modified AR-15 upper without requiring a new lower receiver. It headspaces off the case shoulder, not a belt, which improves consistency and supports accurate handloading. It drives 250 to 270 grain bullets at practical velocities from 16 to 18 inch barrels.
300 PRC. Hornady standardized it with SAAMI in 2018, based on the .375 Ruger case necked down to .30 caliber and designed around 212 to 250 grain high-BC bullets. Like the 338 ARC, it headspaces off the shoulder. Unlike the 338 ARC, it demands a magnum-length bolt-action receiver. You cannot chamber it in an AR-15; the case is simply too large. U.S. SOCOM adopted it for precision sniper applications, which tells you exactly what it was built for.
Ballistics Head to Head
The 300 PRC hits harder at the muzzle. Hornady's 212 gr ELD-X from a 26 inch bolt-gun barrel runs approximately 2,860 fps and around 3,850 ft-lbs. Step up to the 250 gr ELD-M and you are looking at roughly 2,735 fps and 4,154 ft-lbs. The 338 ARC, running a 270 gr ELD-M from an 18 inch AR barrel, produces approximately 2,350 fps and 3,310 ft-lbs. Drop to a 16 inch barrel and velocity falls to the 2,250 to 2,280 fps range, so spec your barrel accordingly.
At 500 yards from a 100-yard zero the gap is real. The 300 PRC's 212 gr ELD-X, with a G7 BC around 0.536, drops roughly 42 to 45 inches. The 338 ARC's 270 gr ELD-M carries a G7 BC around 0.368 and drops closer to 65 to 72 inches. Wind drift tells a similar story. Past 800 yards the 300 PRC wins on paper, and there is no honest way to argue otherwise.
Inside 400 yards, the 338 ARC's numbers are more than adequate for any common game animal, and the supersonic difference never comes up.
Platform and Build Considerations
Your existing AR-15 lower carries over completely for a 338 ARC build. Stock, pistol grip, lower parts kit, buffer tube, all of it stays. What you need is a dedicated upper with a 338 ARC barrel and matching bolt carrier group. Barrel length runs 16 or 18 inches, twist rate should be 1:9 or 1:10 to stabilize 250 to 270 grain projectiles, and you should upgrade to an H2 or H3 buffer because the cartridge generates more bolt thrust than 5.56. One more detail: standard PMAGs do not work. You need magazines with feed geometry designed for this cartridge.
The 300 PRC requires a magnum-length bolt-action receiver. Full stop. Common platforms include Remington 700 footprint actions, the Ruger Precision Rifle, and full custom builds, with barrels running 24 to 26 inches. This is a platform you commit to, not one you adapt from existing parts.
If you want semi-automatic capability, a familiar manual of arms, and fast follow-up shots, the 338 ARC is the only one of these two that gets you there.
Recoil, Suppressors, and Shootability
The 300 PRC generates roughly 30 to 35 ft-lbs of recoil energy in a 10-pound rifle, putting it in .300 Win Mag territory. The non-belted case and efficient powder burn give it a slower push rather than a sharp snap, but it is still a hard-kicking rifle over a long day. The 338 ARC in an AR-15 runs closer to 18 to 22 ft-lbs depending on buffer weight and muzzle device, and the gas system spreads that impulse across a longer cycle.
Suppressing a bolt-action 300 PRC is mechanically simple: thread the can on a 5/8x24 muzzle and you are done. The large case volume limits how much the suppressor can reduce the sound signature, so it earns its keep more in blast and recoil reduction. A suppressed 338 ARC build needs an adjustable gas block. A fixed block will over-gas the rifle with a can attached, causing reliability issues and accelerated wear. On a suppressed build, the adjustable block is not optional.
Hunting and Real-World Use Cases
In mixed timber and cedar country, shots on whitetail and feral hog rarely push past 300 yards. The 338 ARC covers that range completely. The .338-caliber bullet cuts a wide wound channel, and bonded or monolithic loads retain weight through heavy bone, which matters on big hogs and black bear where penetration decides the outcome. The semi-automatic platform is a genuine advantage on hogs: a sounder moves fast in low light, and a bolt gun gives you one shot before the group scatters.
The 300 PRC is built for bigger animals at longer distances. A 212 gr ELD-X still carries over 2,000 ft-lbs at 800 yards, which is enough for an ethical shot on elk or moose where the 338 ARC has already faded. It is also gaining traction in PRS competition as a wind-bucking option at extreme distance. The tradeoff is weight, cost, and a bolt-action manual of arms.
Ammo Cost, Availability, and Reloading
Neither of these is cheap to shoot. The 338 ARC launched in 2023 and factory options are still limited, with Hornady essentially the only source. Plan on ordering online or handloading. The 300 PRC has more factory options, mostly Hornady Precision Hunter and Match loads, at $4 to $7 per round for match-grade ammunition. That adds up fast at volume.
Reloading changes the math on both. The 338 ARC uses a case derived from the 6.5 Grendel parent case, so brass forming is straightforward and standard .338 bullets are widely available and affordable. The 300 PRC burns 75 to 85 grains of slow powder per load, so component costs per round run noticeably higher, especially with match projectiles.
Which Cartridge Fits Your Setup?
Terrain decides the winner as much as ballistics does. If your shots stay inside 500 yards and you already own an AR-15 lower, the 338 ARC covers every shot you will take and does it on a platform you already know. If you travel to open country where 700-plus-yard shots are realistic, a 300 PRC bolt gun makes sense as a dedicated second build.
Still comparing? Read the 338 ARC vs 300 Win Mag breakdown and the 338 ARC vs 308 comparison. When you are ready, browse complete AR uppers or contact the shop at ar15parts.com.
