The 300 Precision Rifle Cartridge (PRC) fires a 0.308-inch diameter bullet from a beltless 2.580-inch case, producing a maximum overall length of 3.700 inches.Designed specifically for extreme long-range dominance, typical bullet weights span from 212 to 250 grains.Factory loads push these heavy projectiles to muzzle velocities between 2,800 and 2,860 fps, generating roughly 3,900 ft-lbs of muzzle energy.The cartridge operates safely at a SAAMI maximum pressure of 65,000 PSI and requires a magnum long-action platform.To properly stabilize its exceptionally long, high-BC bullets, the 300 PRC utilizes a fast 1:8 or 1:8.5 twist rate in standard 24- to 26-inch barrels.
300 PRC Specs
| Specification | 300 PRC |
| Cartridge Name | 300 Precision Rifle Cartridge (300 PRC) |
| Bullet Diameter | 0.308 inches |
| Bullet Weight | 212 grains to 250+ grains |
| Case Length | 2.580 inches |
| Overall Length | 3.700 inches (maximum) |
| Base Diameter | 0.532 inches |
| Throat Diameter | 0.3088 inches |
| Bolt Face | 0.540 inches |
| Shoulder Angle | 30 degrees |
| Maximum Pressure | 65,000 PSI (SAAMI) |
| Typical Twist Rate | 1:8 or 1:8.5 |
| Typical Barrel Length | 24 to 26 inches |
| Muzzle Velocity | 2,800 to 2,860 fps (factory loads) |
| Muzzle Energy | 3,850 to 3,950 ft-lbs |
| Ballistic Coefficient | ~0.673 to 0.777+ (G1) |
| Parent Case | .375 Ruger |
| Platform | Magnum Long Action |
| Supersonic Loads | 212 to 250 grains |
| Subsonic Loads | Not applicable (Dangerous to attempt) |
300 PRC Bullet Diameter
The 300 PRC bullet diameter is exactly 0.308 inches.While it shares this measurement with dozens of standard .30 caliber rounds like the .308 Winchester, the PRC chamber features a tighter throat diameter (0.3088 inches) specifically engineered to perfectly align modern, aerodynamic bullets before they engage the rifling.
300 PRC Case Length
The 300 PRC case length is 2.580 inches from the rim to the case mouth. Because the cartridge is beltless and headspaces off a 30-degree shoulder, this case length provides massive internal capacity—holding up to 80 grains of slow-burning powder without compromising brass life.
300 PRC Overall Length
SAAMI established the 300 PRC overall length at a maximum of 3.700 inches.This exceptional length is the defining characteristic of the cartridge, as it allows long, heavy, high-BC bullets to be seated completely outside of the powder column, maximizing propellant capacity and accuracy.
300 PRC Bullet Weights
Standard 300 PRC bullet weights are significantly heavier than older .30 caliber magnums. The cartridge is optimized around 212-grain and 225-grain match and hunting projectiles, with custom handloaders often pushing into 230-grain and 250-grain territory for Extreme Long Range (ELR) shooting.
300 PRC Muzzle Velocity
The 300 PRC muzzle velocity heavily depends on barrel length, but factory specifications rate a 212-grain bullet at 2,860 fps and a 225-grain bullet at 2,810 fps from a 24-inch test barrel.
300 PRC Muzzle Energy
Pushing massive bullets at high speeds results in devastating 300 PRC muzzle energy, generally starting between 3,850 and 3,950 foot-pounds.This translates to superior kinetic energy retention at distances beyond 1,000 yards.
300 PRC Maximum Pressure
The 300 PRC maximum average pressure established by SAAMI is 65,000 PSI. This high operating pressure takes full advantage of modern rifle actions and advanced progressive propellants.
300 PRC Twist Rate
To stabilize extreme-length projectiles, the standard 300 PRC twist rate is mandated at 1:8 or 1:8.5 inches.Older magnums typically relied on 1:10 twist rates, which fail to properly spin modern 225+ grain bullets.
300 PRC Barrel Length
The 300 PRC barrel length is traditionally 24 to 26 inches. The large case capacity dictates that the powder needs a long runway to achieve full combustion; cutting the barrel shorter than 24 inches wastes powder in a blinding muzzle flash.
300 PRC Ballistic Coefficient
The 300 PRC ballistic coefficient (BC) is best-in-class for the .30 caliber family. A factory 212-grain ELD-X boasts a G1 BC of 0.673, while the 225-grain ELD Match pushes a staggering G1 BC of 0.777, allowing it to easily slice through crosswinds and retain velocity.
Supersonic vs Subsonic
The 300 PRC is a dedicated, hyper-efficient supersonic magnum. Unlike smaller .30 caliber cartridges, it is entirely unsuited for subsonic applications.
| Load Type | Typical Bullet Weight | Velocity | Muzzle Energy | Main Characteristic |
| Supersonic | 212 – 225 grains | 2,800 – 2,860 fps | ~3,900 ft-lbs | Dominant long-range ballistics, stays supersonic past 1,500 yards |
| Subsonic | N/A | N/A | N/A | Highly dangerous; downloading massive magnum cases causes erratic ignition |
Attempting to download a case designed to hold 80+ grains of slow-burning powder to achieve 1,000 fps creates extreme safety hazards. Reduced charges can result in the deadly secondary explosion effect (SEE) or dangerous squib loads stuck in the barrel.
Factory Load Specifications
Because it is a precision-focused cartridge, factory 300 PRC loads prioritize heavy, high-BC bullets. (Data based on standard 24-inch test barrels).
- 212 grain: Hornady Precision Hunter ELD-X (Supersonic). Velocity: 2,860 fps. Muzzle Energy: 3,850 ft-lbs. G1 BC: 0.673.
- 225 grain: Hornady TAP / ELD Match (Supersonic). Velocity: 2,810 fps. Muzzle Energy: 3,945 ft-lbs. G1 BC: 0.777.
Cartridge Dimensions
The 300 PRC dimensions utilize a beltless, non-rebated design that perfectly aligns with a magnum bolt face.
| Dimension | Measurement |
| Bullet Diameter | 0.308 inches |
| Case Length | 2.580 inches |
| Overall Length | 3.700 inches |
| Base Diameter | 0.532 inches |
| Throat Diameter | 0.3088 inches |
| Bolt Face | 0.540 inches |
| Shoulder Angle | 30 degrees |
Barrel Length
Barrel length heavily dictates 300 PRC performance. Because the cartridge relies on a massive charge of slow-burning, progressive powder, it requires significant bore time to achieve complete combustion and reach its maximum velocity potential.
- 20 inches: ~2,675 fps. Sacrifices roughly 150 fps and creates a blinding muzzle flash and severe blast due to unburnt powder.
- 24 inches: ~2,775 fps. Offers an excellent balance of field mobility and magnum terminal performance.
- 26 inches: ~2,825 fps. The absolute sweet spot for the cartridge, fully burning the powder charge to dominate PRS matches.
- 30 inches: ~2,925 fps. Extracts the absolute maximum velocity for Extreme Long Range (ELR) shooting, though the rifle becomes exceptionally heavy.
Ballistics
To understand 300 PRC ballistics, it is best viewed at extreme distances. This is standard trajectory data for the 212-grain Hornady ELD-X load with a 100-yard zero:
- Muzzle: 2,860 fps | 3,850 ft-lbs | Drop: -1.5 in
- 100-yard: 2,725 fps | 3,495 ft-lbs | Drop: 0.0 in (Zero)
- 300-yard: 2,512 fps | 2,970 ft-lbs | Drop: -11.06 in
- 600-yard: 2,150 fps | 2,175 ft-lbs | Drop: -70.64 in
- 1000-yard: 1,680 fps | 1,325 ft-lbs | Drop: -245.0 in
Platform And Compatibility
To build or buy a 300 PRC, specific platform requirements must be met to accommodate the 3.700-inch cartridge.
- Action Length: Requires a true Magnum Long Action. The internal magazine box must be at least 3.700 inches long.
- Bolt Requirements: Uses a standard 0.540-inch magnum bolt face, making it mechanically straightforward to rebarrel from a .300 Win Mag.
- Twist Rate:Barrels must be cut with a 1:8 or 1:8.5 twist rate to stabilize the heavy 225+ grain bullets.
300 PRC vs 300 Win Mag
While both fire .30 caliber bullets, their foundational designs reflect different eras of ballistic engineering.
| Specification | 300 PRC | 300 Win Mag |
| Bullet Diameter | 0.308 inches | 0.308 inches |
| Typical Bullet Weight | 212 gr – 250 gr | 150 gr – 200 gr |
| Case Design | Beltless, 30° Shoulder | Belted, 25° Shoulder |
| Overall Length | 3.700 inches | 3.340 inches |
| Twist Rate | 1:8 or 1:8.5 | 1:10 (Standard) |
| 500-Yard Energy | ~2,330 ft-lbs | ~1,800 ft-lbs |
| Primary Design Focus | High-BC, Heavy Bullets, 1,000+ Yards | Traditional Hunting, Moderate Ranges |
Pros And Cons
300 PRC Pros
- The 3.700-inch overall length keeps long bullets entirely outside the powder column, maximizing case capacity and velocity consistency.
- The beltless case headspaces precisely off the 30-degree shoulder, extending brass life and improving inherent accuracy.
- Standard fast twist rates (1:8) perfectly stabilize modern, high-BC bullets that resist wind drift past 1,000 yards.
- Delivers substantially more kinetic energy on target at 500+ yards than standard .30 caliber magnums.
300 PRC Cons
- Factory ammunition is expensive and less commonly found on standard sporting goods shelves compared to legacy cartridges.
- Requires a specialized magnum-length action (3.70-inch magazine box) to feed correctly.
- Generates stout recoil (roughly 42 ft-lbs), demanding a heavy rifle profile or an aggressive muzzle brake to manage.
FAQs
What are the specifications of 300 PRC?
The 300 PRC fires a 0.308-inch bullet from a beltless 2.580-inch case. With a maximum overall length of 3.700 inches and an operating pressure of 65,000 PSI, it is engineered for extreme long-range precision and big game hunting.
What is the bullet diameter of 300 PRC?
The 300 PRC uses a standard 0.308-inch diameter bullet.
What is the case length of 300 PRC?
The SAAMI specification for the 300 PRC case length is 2.580 inches (measured from the rim to the case mouth).
What is the overall length of 300 PRC?
The maximum overall length of the 300 PRC is 3.700 inches. This exceptional length is required to seat highly aerodynamic, heavy bullets without intruding into the powder capacity.
What bullet weights are available for 300 PRC?
Standard factory 300 PRC ammunition utilizes heavy 212-grain and 225-grain bullets. Handloaders often stretch this up to 230-grain or 250-grain projectiles for extreme distances.
What is the muzzle velocity of 300 PRC?
From a standard 24-inch or 26-inch barrel, the 300 PRC muzzle velocity generally falls between 2,800 and 2,860 fps when firing 212- to 225-grain bullets.
What is the muzzle energy of 300 PRC?
The 300 PRC produces massive kinetic energy, typically generating between 3,850 and 3,950 foot-pounds of energy at the muzzle.
What is the maximum pressure of 300 PRC?
The SAAMI maximum average pressure (MAP) for the 300 PRC is 65,000 PSI.
What is the twist rate for 300 PRC?
To properly spin and stabilize its massive projectiles, the standard 300 PRC twist rate is a fast 1:8 or 1:8.5 inches.
What is the heaviest 300 PRC bullet?
While factory loads max out around 225 grains, boutique manufacturers and precision handloaders often utilize custom 250-grain solid copper or match bullets.
Is 300 PRC subsonic?
No, the 300 PRC is exclusively a supersonic magnum. Attempting to under-load the massive case to reach subsonic speeds is incredibly dangerous and can lead to catastrophic weapon failure.
Is 300 PRC supersonic?
Yes, the cartridge is entirely focused on retaining supersonic velocity as far out as possible, often staying supersonic well beyond 1,500 yards.
What barrel length is best for 300 PRC?
A 26-inch barrel is widely considered the sweet spot for the 300 PRC, as it provides enough length to achieve full combustion of the slow-burning powder and reach peak velocities.
Is 300 PRC compatible with a standard long action?
It requires a magnum long action. The magazine box must measure at least 3.700 inches internally, and the bolt requires a 0.540-inch magnum bolt face.
How does 300 PRC compare with 300 Win Mag?
While both are .30 caliber magnums, the 300 PRC features a modern beltless case, a faster twist rate, and a longer overall length. This allows the PRC to fire heavier, more aerodynamic bullets that outperform the 300 Win Mag in wind deflection and retained energy past 800 yards.