Published: January 2026 | Last updated: April 2026
Disclaimer: All load data referenced in this article applies only to Weatherby double-radius shoulder chambers with standard freebore. Do not use this data in non-Weatherby chambers. The 7mm Weatherby Magnum operates at 63,817 PSI. Always begin 10% below published maximum charges and work up carefully. Large rifle magnum primers are required.
The 7mm Weatherby Magnum was introduced in 1944 by Roy Weatherby – making it one of the first Weatherby cartridges and among the oldest proprietary 7mm magnums available. Weatherby developed it by necking down the .300 H&H Magnum case to accept .284-inch bullets, then applying his distinctive double-radius shoulder profile. The result was the fastest production 7mm cartridge for several decades, pushing 140-grain bullets to 3,250 FPS from a 26-inch Weatherby Mark V barrel.
The 7mm Weatherby Magnum is the .284-inch equivalent of the 300 Weatherby Magnum in design philosophy and operating characteristics. Both use the same double-radius shoulder, both require Weatherby chambers with extended freebore, and both deliver maximum velocity at the cost of barrel life and Weatherby-specific platform requirements. The 7mm Weatherby produces less recoil than the 300 Weatherby while delivering comparable long-range performance on deer to elk-sized game.
The Weatherby Double-Radius Shoulder: Critical Platform Information
The 7mm Weatherby Magnum shares the same Weatherby design architecture as the 300 Weatherby Magnum. These requirements apply equally to the 7mm version:
Chamber requirement: The 7mm Weatherby Magnum requires a Weatherby chamber – either a genuine Weatherby Mark V or Vanguard, or a custom rifle built specifically with a Weatherby reamer. The extended freebore is integral to the cartridge’s pressure management and must be present in the chamber. Loading 7mm Weatherby Magnum ammunition in a non-Weatherby chamber will produce dangerously elevated pressure.
Bullet seating: Do not seat bullets to contact the lands in a standard Weatherby chamber. The extended freebore means bullets jump significantly before engaging the rifling. The cartridge is optimized for this configuration and performs correctly at standard SAAMI OAL.
Data validity: All load data for the 7mm Weatherby Magnum applies to Weatherby chambers with standard freebore only. Do not substitute 7mm Remington Magnum or other 7mm magnum data. 7mm Weatherby brass is not interchangeable with other 7mm magnum cases.
For the complete explanation of Weatherby’s double-radius shoulder and freebore system, see the 300 Weatherby Magnum complete guide.
Technical Characteristics
| Characteristic | Value |
|---|---|
| Bullet Diameter | 0.284 inches (7mm) |
| Case Length | 2.549 inches |
| Overall Cartridge Length | 3.340 inches (max) |
| Case Capacity | ~88-90 grains H2O |
| Case Type | Belted, double-radius shoulder |
| Belt Diameter | 0.532 inches |
| Max Avg Pressure (SAAMI) | 63,817 PSI |
| Typical Bullet Weight | 120-175 gr |
| Muzzle Velocity (140 gr, 26-in) | ~3,250 FPS |
| Muzzle Velocity (160 gr, 26-in) | ~3,050 FPS |
| Muzzle Velocity (175 gr, 26-in) | ~2,925 FPS |
| Muzzle Energy (140 gr) | ~3,283 ft-lbs |
The 26-inch Weatherby Mark V barrel produces the published velocity figures. From 24-inch barrels (Vanguard and some Mark V variants), expect approximately 50-70 FPS less. Barrel life is 1,500-2,500 rounds before accuracy degradation – shorter than the 7mm Remington Magnum but similar to other Weatherby cartridges at equivalent velocities.
7mm Weatherby vs 7mm Remington Magnum
This is the comparison every buyer considers. Both are full-size 7mm magnums in long-action rifles.
| Factor | 7mm Weatherby Magnum | 7mm Remington Magnum | Notes |
|---|---|---|---|
| MV (140 gr) | 3,250 FPS | 3,100-3,175 FPS | Weatherby 75-150 FPS faster |
| MV (160 gr) | 3,050 FPS | 2,950-3,000 FPS | Weatherby faster |
| Recoil | 23-26 ft-lbs | 20-23 ft-lbs | Weatherby noticeably more |
| Chamber required | Weatherby only | Standard | 7mm Rem Mag broader |
| Factory ammo | Limited | Excellent | 7mm Rem Mag far broader |
| Rifle selection | Limited | Excellent | 7mm Rem Mag far broader |
| Barrel life | 1,500-2,500 rds | 3,000-4,000 rds | 7mm Rem Mag better |
The 7mm Remington Magnum produces 75-150 FPS less velocity but with significantly better availability, broader rifle selection, and longer barrel life. For most hunters, the 7mm Remington Magnum is the more practical choice unless maximum 7mm velocity from a standard magnum case is specifically required.
Recoil
At approximately 23-26 ft-lbs in a standard 9-pound hunting rifle, the 7mm Weatherby Magnum produces noticeably more recoil than the 7mm Remington Magnum.
| Cartridge | Recoil (ft-lbs) | Rifle Weight (lbs) | Notes |
|---|---|---|---|
| 280 Remington | 17-18 | 8.0 | Moderate; pleasant |
| 7mm Remington Magnum | 20-23 | 9.0 | Full magnum; manageable |
| 7mm Weatherby Magnum | 23-26 | 9.0 | More than 7mm Rem Mag; muzzle brake advised |
| 300 Weatherby Magnum | ~35 | 9.0 | Significantly heavier |
A muzzle brake reduces felt recoil by 40-50% and makes extended shooting sessions comfortable. Most serious 7mm Weatherby Magnum shooters include a brake on their rifle.
Ballistics and Field Performance
Trajectory
| Distance (yards) | Velocity (FPS) | Energy (ft-lbs) | Drop (inches) |
|---|---|---|---|
| Muzzle | 3,250 | 3,283 | -1.5 |
| 50 | 3,142 | 3,069 | +0.3 |
| 100 | 3,037 | 2,869 | +1.0 |
| 150 | 2,934 | 2,677 | +0.7 |
| 200 | 2,833 | 2,496 | 0.0 |
| 300 | 2,638 | 2,164 | -5.3 |
| 400 | 2,450 | 1,866 | -16.0 |
| 500 | 2,269 | 1,601 | -33.0 |
| 600 | 2,096 | 1,367 | -57.5 |
140-grain hunting bullet, BC 0.531, 3,250 FPS muzzle velocity. 59°F, sea level, 1.5-inch sight height, 200-yard zero.
At 500 yards the 7mm Weatherby delivers 1,601 ft-lbs – adequate for elk. At 600 yards it is at 1,367 ft-lbs, approaching the lower boundary for elk-sized game. The cartridge’s practical elk hunting range extends to 500-550 yards with confidence.
Comparison with 7mm Alternatives
| Cartridge | Bullet (gr) | MV (FPS) | Energy @400 yds | Drop @400 yds |
|---|---|---|---|---|
| 280 Remington | 150 | 2,900 | ~1,583 ft-lbs | ~19 in |
| 7mm Remington Magnum | 140 | 3,100 | ~1,750 ft-lbs | ~17 in |
| 7mm Weatherby Magnum | 140 | 3,250 | ~1,866 ft-lbs | ~16 in |
| 7mm PRC | 160 | 2,960 | ~1,920 ft-lbs | ~17 in |
Reloading the 7mm Weatherby Magnum
Primers
Large rifle magnum primers are mandatory.
| Primer | Type | Application |
|---|---|---|
| Federal 215 | Large Rifle Magnum | Top choice; hottest standard primer; slow powders |
| CCI 250 | Large Rifle Magnum | Reliable; consistent; widely available |
| Federal GM215M | Large Rifle Magnum Match | Precision loads; lowest SD |
| Remington 9-1/2M | Large Rifle Magnum | Dependable; hunting loads |
| Winchester WLRM | Large Rifle Magnum | Consistent; works with slow powders |
Cases
Weatherby, Norma, and Peterson produce 7mm Weatherby Magnum brass. Standard 7mm magnum brass from other manufacturers is not compatible with the 7mm Weatherby’s longer case and double-radius shoulder.
| Brand | Notes |
|---|---|
| Weatherby | Primary manufacturer; most available; adequate quality |
| Norma | Premium quality; excellent consistency; better case life |
| Peterson | Premium quality; tight tolerances; available from specialty dealers |
Belted case sizing: full-length size after every firing. The belt controls headspace. Monitor case head wall thickness above the belt after 4-5 firings. Trim to 2.539 inches after each firing. Anneal every 3-4 firings.
Bullets
The 7mm Weatherby Magnum uses standard .284-inch (7mm) bullets from the same library as the 7mm Remington Magnum and 7mm PRC.
| Bullet | Weight | Type | Application | Notes |
|---|---|---|---|---|
| Nosler Ballistic Tip | 120 gr | BT | Deer, antelope; maximum velocity | Very high velocity at close range |
| Sierra GameKing | 140 gr | SBT | Deer, antelope; flat trajectory | Classic choice; accurate; reliable |
| Nosler AccuBond | 140 gr | Bonded BT | Deer, elk; versatile | Bonded handles high close-range impact |
| Hornady ELD-X | 150 gr | Polymer Tip | Deer, elk at range | High BC; controlled expansion |
| Nosler AccuBond | 160 gr | Bonded BT | Elk, large game | Good BC; bonded; recommended for elk |
| Sierra GameKing | 160 gr | SBT | Deer, elk; general hunting | Accurate; reliable |
| Hornady ELD-X | 162 gr | Polymer Tip | Elk; long-range hunting | High BC; excellent all-around |
| Nosler Partition | 160 gr | Partition | Elk, moose; tough game | Maximum penetration; controlled expansion |
| Berger VLD Hunting | 168 gr | VLD | Long-range hunting | High BC; precision hunting |
| Nosler AccuBond | 175 gr | Bonded BT | Elk, large game at range | Heaviest bonded option; best penetration |
| Barnes TSX | 140 gr | Copper HP | Lead-free; tough game | Deep penetration; California legal |
At 3,250 FPS with 140-grain bullets, lightly constructed cup-and-core hunting bullets can fail at close-range impact on elk and moose. Use bonded construction or partition-style bullets for all large game hunting.
Powders
The 7mm Weatherby Magnum’s 88-90 grain case requires slow-burning powders – slower than the 7mm Remington Magnum‘s standard H4831SC and H4350 choices, in the H1000/Retumbo range.
| Powder | Bullet Weight | Start Charge | Max Charge | Approx Velocity | Notes |
|---|---|---|---|---|---|
| Hodgdon H1000 | 140-160 gr | 76.0 gr | 85.0 gr | ~3,280 FPS | Top choice; consistent; most data; widely available |
| Hodgdon H1000 | 160-175 gr | 74.0 gr | 83.0 gr | ~3,060 FPS | Good with heavier hunting bullets |
| Hodgdon Retumbo | 140-175 gr | 77.0 gr | 86.0 gr | ~3,280 FPS | Maximum velocity; ball powder; excellent metering |
| Alliant Reloder 22 | 140-175 gr | 74.0 gr | 83.0 gr | ~3,230 FPS | Good all-around; long-proven choice |
| Alliant Reloder 26 | 140-162 gr | 75.0 gr | 84.0 gr | ~3,240 FPS | Temperature stable; top hunting choice |
| Alliant Reloder 25 | 160-175 gr | 74.0 gr | 83.0 gr | ~3,060 FPS | Good with heavier bullets; consistent |
| IMR 7828 SSC | 140-160 gr | 74.0 gr | 83.0 gr | ~3,200 FPS | Short cut; good metering; accurate |
| IMR 7977 Enduron | 140-160 gr | 74.0 gr | 83.0 gr | ~3,210 FPS | Temperature stable; reduced copper fouling |
| Vihtavuori N560 | 160 gr | 74.0 gr | 83.0 gr | ~3,120 FPS | Temperature stable; premium consistency |
| IMR 4831 | 140-162 gr | 73.0 gr | 82.0 gr | ~3,160 FPS | Classic magnum powder; versatile |
| Hodgdon H4831SC | 140-150 gr | 71.0 gr | 80.0 gr | ~3,200 FPS | Slightly faster; lighter bullets only |
| Accurate MagPro | 150-162 gr | 73.0 gr | 82.0 gr | ~3,140 FPS | Ball powder; good metering |
| Norma MRP | 140-175 gr | 73.0 gr | 82.0 gr | ~3,180 FPS | Good consistency; natural pairing with Norma brass |
All charge weights apply only to Weatherby double-radius shoulder chambers with standard freebore. Verify against current Hodgdon, Alliant, or Norma published data before loading. Begin 10% below listed maximums.
Hodgdon H1000 is the most practical starting point for 7mm Weatherby Magnum load development. Its burn rate is well-matched across the practical bullet weight range, it is widely available, and it has the most published data for this cartridge.
Alliant Reloder 26 is the temperature-stable choice for hunters who develop loads in controlled conditions and use them in cold mountain air. Its performance consistency is the best of the common slow-burning magnum powders.
Practical Hunting Applications
Elk and Large Game
With a 160-grain Nosler AccuBond at 3,050 FPS, the 7mm Weatherby Magnum delivers 1,866 ft-lbs at 400 yards and 1,601 ft-lbs at 500 yards – adequate for ethical elk kills at those distances with quality bonded bullets and precise shot placement. The flat trajectory and high velocity provide a practical advantage in open Western country where holdover estimation at unknown distances is required.
Mountain Sheep and Goat
The 7mm Weatherby Magnum’s flat trajectory and light 140-grain loads at 3,250 FPS are well-suited to mountain hunting where shots at 400-600 yards are realistic and field-estimated distances. The rifle’s long-action Weatherby Mark V is heavier than purpose-built compact mountain rifles, but the ballistic performance is excellent for the application.
Conclusion
The 7mm Weatherby Magnum is the fastest standard-production 7mm magnum cartridge – a title it has held since 1944. For hunters who own a Weatherby Mark V and want the maximum 7mm velocity available, the cartridge delivers on its promise.
Its practical limitations in 2026 are the same as for the 300 Weatherby Magnum: Weatherby-specific chamber requirements, limited rifle availability outside the Mark V/Vanguard line, premium brass sourcing, and shorter barrel life than the 7mm Remington Magnum. For hunters building a new rifle, the 7mm Remington Magnum provides 90-95% of the performance with substantially better availability, and the 7mm PRC offers similar or better 400+ yard performance with modern non-belted case design. For hunters who already own and shoot a 7mm Weatherby Magnum Mark V, the cartridge is excellent and fully worth loading for.
For related reading, see 7mm Weatherby Magnum ballistics, 7mm Remington Magnum complete guide, 7mm PRC complete guide, and 300 Weatherby Magnum complete guide.
Disclaimer: All load data in this article applies exclusively to Weatherby double-radius shoulder chambers with standard freebore. Verify all charges against current published Weatherby, Hodgdon, or Alliant data before loading. Large rifle magnum primers are required. Never exceed published maximum charges. Always begin 10% below listed maximums and work up while monitoring for pressure signs.
Editorial note: This article was originally published in January 2026 and revised in April 2026. The revision added the Weatherby double-radius shoulder critical platform section (with reference to the 300 Weatherby guide for full explanation), a direct 7mm Weatherby vs 7mm Remington Magnum comparison table across seven factors, corrected the ballistics table to 200-yard zero per site standard with data from muzzle to 600 yards, a four-cartridge comparison table with energy and drop at 400 yards, a complete powder table with 13 powders and charge weight ranges, expanded bullet selection with 11 bullets and cup-and-core warning at Weatherby velocities, barrel life comparison context, and honest 2026 positioning relative to 7mm Rem Mag and 7mm PRC.
