Published: January 2026 | Last updated: April 2026
Disclaimer: All load data referenced in this article is drawn from published reloading manuals. The 338 Federal operates at 62,000 PSI. Always begin 10% below published maximum charges and work up carefully. Never exceed published maximums.
The 338 Federal was introduced in 2006 as a collaboration between Federal Cartridge and Sako. The concept was straightforward and technically sound: take the 308 Winchester case and neck it up to accept .338-inch bullets. The result is a short-action cartridge that pushes 200-grain .338-inch bullets at 2,630 FPS and 185-grain bullets at 2,750 FPS – delivering elk-class terminal performance from the same compact case that makes the 308 Winchester the dominant choice in short-action hunting rifles.
The proposition makes sense when you examine the terminal ballistics numbers. A 200-grain .338-inch bullet has a sectional density of 0.250 – higher than a 180-grain .308-inch bullet at 0.271, though the 338 Federal’s modest velocity limits its BC advantage at longer ranges. What the 338 Federal offers that the 308 Winchester cannot is a heavier, wider bullet that drives through heavy bone, muscle, and hide on elk and bears with more authority. At 300 yards inside timber where most elk are actually shot, the 338 Federal’s terminal performance is a genuine step up from the 308.
The cartridge has a loyal following despite modest factory ammunition availability, primarily among hunters who work in heavy cover where short-range, heavy-cover encounters with large game require a cartridge with more terminal authority than the 308 Winchester delivers.
Technical Characteristics
| Characteristic | Value |
|---|---|
| Bullet Diameter | 0.338 inches |
| Case Length | 2.015 inches |
| Overall Cartridge Length | 2.820 inches |
| Case Capacity | ~56-57 grains H2O |
| Case Type | Rimless, bottleneck |
| Parent Case | 308 Winchester (necked up) |
| Max Avg Pressure (SAAMI) | 62,000 PSI |
| Typical Bullet Weight | 180-225 gr |
| Muzzle Velocity (185 gr) | ~2,750 FPS |
| Muzzle Velocity (200 gr) | ~2,630 FPS |
| Muzzle Velocity (210 gr) | ~2,550 FPS |
| Muzzle Energy (200 gr) | ~3,074 ft-lbs |
The 308 Winchester Connection
The 338 Federal’s case is the 308 Winchester case with the neck expanded to accept .338-inch bullets. This heritage has significant practical implications for the reloader:
- Standard 308 Winchester brass can be necked up to 338 Federal using a 338 Federal sizing die, avoiding the need to source the relatively scarce 338 Federal headstamped brass
- The same shell holder used for 308 Winchester works for 338 Federal
- The same bolt face accommodates both cartridges, and many short-action rifles can be converted from 308 to 338 Federal with a barrel change
- Powder selection overlaps heavily with the 308 Winchester
For a reloader who already works with the 308 Winchester, transitioning to the 338 Federal is more straightforward than working with a completely different case family. Much of the process is identical with the exception of bullet diameter and powder charge.
Twist Rate
The 338 Federal’s 180-225 grain bullet range covers a meaningful range of bullet lengths requiring appropriate twist rates.
| Twist Rate | Optimal Bullet Weight | Notes |
|---|---|---|
| 1:9 | 200-225 gr | Best for heaviest hunting bullets; handles all practical weights |
| 1:9.5 | 185-210 gr | Handles most practical hunting weights adequately |
| 1:10 | 180-200 gr | Adequate for standard weights; limits use of heaviest bullets |
Most production 338 Federal rifles use 1:10 or 1:9.5 twist. For hunters who want to run 210-225 grain heavy bullets for elk and bear, verify your barrel’s twist rate can stabilize these longer projectiles. A 1:9 twist handles all practical 338 Federal bullet weights.
Recoil
At approximately 22-25 ft-lbs in a standard 8-pound rifle, the 338 Federal is noticeably more than the 308 Winchester and approaches full magnum territory. In a light 7-pound AR-10 build, the felt recoil is sharper.
| Cartridge | Recoil (ft-lbs) | Rifle Weight (lbs) | Notes |
|---|---|---|---|
| 308 Winchester | 15-18 | 8.5 | The parent case; lighter and excellent |
| 35 Whelen | 22-25 | 8.5 | Close competitor; long-action |
| 338 Federal | 22-25 | 8.0 | Short-action; same energy class as 35 Whelen |
| 338 Winchester Magnum | 28-35 | 9.0 | Significantly more; longer range |
| 300 Winchester Magnum | 22-25 | 9.0 | Similar class; .30-caliber magnum |
The 338 Federal’s recoil is real and more than the parent 308 Winchester. Hunters who develop loads on the bench benefit from a recoil pad and shooting bags – the 200-grain loads at 2,630 FPS with large powder charges produce enough recoil to fatigue a shooter during an extended development session.
Ballistics and Field Performance
Trajectory
| Distance (yards) | Velocity (FPS) | Energy (ft-lbs) | Drop (inches) |
|---|---|---|---|
| Muzzle | 2,630 | 3,074 | -1.5 |
| 50 | 2,502 | 2,782 | +0.6 |
| 100 | 2,378 | 2,512 | +1.5 |
| 150 | 2,257 | 2,265 | +1.2 |
| 200 | 2,140 | 2,036 | 0.0 |
| 300 | 1,918 | 1,635 | -7.5 |
| 400 | 1,709 | 1,299 | -23.0 |
| 500 | 1,514 | 1,018 | -49.5 |
200-grain hunting bullet, BC 0.416, 2,630 FPS muzzle velocity. 59°F, sea level, 1.5-inch sight height, 200-yard zero.
At 300 yards the 338 Federal delivers 1,635 ft-lbs – adequate for elk with quality bullets and precise shot placement. At 400 yards it is at 1,299 ft-lbs, marginal for elk and declining toward the practical limit for large game. The 338 Federal is most effective inside 350 yards, where its heavier bullet weight and energy delivery make a practical difference over the 308 Winchester.
Where the 338 Federal Fits: The Practical Comparison
| Cartridge | Bullet (gr) | MV (FPS) | Energy @200 yds | Energy @300 yds | Action |
|---|---|---|---|---|---|
| 308 Winchester | 180 | 2,620 | ~1,986 ft-lbs | ~1,649 ft-lbs | Short |
| 338 Federal | 200 | 2,630 | ~2,036 ft-lbs | ~1,635 ft-lbs | Short |
| 35 Whelen | 200 | 2,675 | ~2,100 ft-lbs | ~1,720 ft-lbs | Long |
| 338 Winchester Magnum | 225 | 2,800 | ~2,700 ft-lbs | ~2,260 ft-lbs | Long |
The 338 Federal and 308 Winchester carry nearly the same energy at 200-300 yards, but the 338 Federal delivers that energy through a heavier, wider .338-inch bullet with higher sectional density. The practical advantage is terminal performance on large, tough-bodied animals like elk, bears, and moose where bullet construction and diameter determine penetration depth. The 35 Whelen occupies similar ballistic territory but requires a long-action rifle; the 338 Federal fits a standard short action.
Reloading the 338 Federal
Primers
Large rifle primers are standard for the 338 Federal. The cartridge’s moderate operating pressure does not require magnum primers.
| Primer | Type | Application |
|---|---|---|
| CCI 200 | Large Rifle | Standard choice for all loads; reliable |
| Federal 210 | Large Rifle | Good consistency; dependable ignition |
| Federal GM210M | Large Rifle Match | Precision loads; lowest SD |
| Remington 9-1/2 | Large Rifle | Traditional choice; dependable |
| Winchester WLR | Large Rifle | Reliable; good for hunting loads |
| CCI 250 | Large Rifle Magnum | Slowest powders at max charges in cold conditions |
Cases
Federal and Norma are the primary sources of 338 Federal headstamped brass. However, 308 Winchester brass from any manufacturer can be necked up to 338 Federal with a sizing die.
| Brand | Notes |
|---|---|
| Federal | Original co-developer; headstamped brass; good quality |
| Norma | Premium quality; excellent consistency; good for precision work |
| Winchester (308 Win necked up) | Widely available; consistent; requires neck-up forming step |
| Hornady (308 Win necked up) | Good quality; consistent; requires neck-up forming step |
| Lapua (308 Win necked up) | Premium quality; best case life; requires neck-up forming step |
Using necked-up 308 Winchester brass: run the case through a 338 Federal full-length sizing die, which expands the neck to .338-inch. The case body dimensions are identical. Trim to 2.005 inches after forming and sizing. This is a simple and practical alternative to sourcing the relatively scarce 338 Federal headstamped brass.
Trim to 2.005 inches after each firing. The rimless case headspaces on the shoulder. Full-length size after every firing for reliable function. Anneal every 4-5 firings.
Bullets
The 338 Federal uses .338-inch bullets shared with the 338 Winchester Magnum and other .338-caliber cartridges. The practical hunting range is 180-225 grains, with 200-210 grains being the sweet spot for elk-class hunting.
| Bullet | Weight | Type | Application | Notes |
|---|---|---|---|---|
| Nosler AccuBond | 180 gr | Bonded BT | Deer, bear; versatile | Good BC; bonded; reliable expansion |
| Sierra GameKing | 185 gr | SBT | Deer, elk at moderate range | Flat; accurate; good for deer |
| Barnes TSX | 185 gr | Copper HP | Lead-free; tough game | Deep penetration; California legal |
| Hornady InterLock | 200 gr | SP | Deer, elk; economical | Traditional; proven; widely available |
| Hornady ELD-X | 200 gr | Polymer Tip | Deer, elk; long-range | High BC for weight; controlled expansion |
| Nosler AccuBond | 200 gr | Bonded BT | Elk, large game | Good BC; bonded; recommended for elk |
| Nosler Partition | 200 gr | Partition | Elk, moose, bear | Maximum penetration; controlled expansion |
| Barnes TSX | 210 gr | Copper HP | Large bear, elk; tough angles | Deep penetration; lead-free |
| Nosler Partition | 210 gr | Partition | Elk, moose; heavy game | Heavy; best penetration on large animals |
| Sierra GameKing | 225 gr | SBT | Large game; maximum bullet weight | Heaviest standard option; deep penetration |
The 200-grain Nosler Partition and Nosler AccuBond are the consensus choices for elk and bear hunting with the 338 Federal. Both provide the controlled expansion and deep penetration that makes the .338-inch bore valuable on large animals, and both are designed to perform reliably at the 338 Federal’s moderate velocities rather than requiring the high-velocity impact of a magnum to initiate expansion.
Powders
The 338 Federal uses the same powder burn rate range as the 308 Winchester – medium-burning powders that fill the case adequately without position sensitivity. Hodgdon Varget and IMR 4064 are the primary starting points.
| Powder | Bullet Weight | Start Charge | Max Charge | Approx Velocity | Notes |
|---|---|---|---|---|---|
| Hodgdon Varget | 180-200 gr | 44.0 gr | 49.5 gr | ~2,700 FPS | Top choice; temperature stable; most published data |
| Hodgdon Varget | 200-210 gr | 42.5 gr | 48.0 gr | ~2,600 FPS | Good with heavier hunting bullets |
| IMR 4064 | 180-200 gr | 43.5 gr | 49.0 gr | ~2,680 FPS | Classic choice; accurate; versatile |
| IMR 4064 | 200-210 gr | 42.0 gr | 47.5 gr | ~2,570 FPS | Works with heavier bullets |
| Hodgdon H4895 | 185-210 gr | 43.0 gr | 48.5 gr | ~2,660 FPS | Temperature stable; consistent |
| Alliant Reloder 15 | 180-200 gr | 44.0 gr | 49.5 gr | ~2,700 FPS | Good velocity; consistent |
| IMR 4895 | 180-200 gr | 43.0 gr | 48.5 gr | ~2,670 FPS | Proven in .338 bore; versatile |
| Winchester 748 | 185-210 gr | 43.5 gr | 49.0 gr | ~2,660 FPS | Ball powder; good metering; versatile |
| Hodgdon Benchmark | 180-200 gr | 42.5 gr | 48.0 gr | ~2,660 FPS | Precision loads; good consistency |
| Vihtavuori N140 | 185-210 gr | 43.0 gr | 48.5 gr | ~2,650 FPS | Premium consistency; good for precision hunting loads |
| Ramshot TAC | 200-225 gr | 42.0 gr | 47.5 gr | ~2,570 FPS | Ball powder; good with heavier bullets |
| Alliant Reloder 19 | 210-225 gr | 43.5 gr | 49.0 gr | ~2,560 FPS | Good with heaviest bullets |
| IMR 3031 | 180-185 gr | 40.5 gr | 46.0 gr | ~2,650 FPS | Faster burn; lighter bullets only |
All charge weights are reference figures. Verify against current published data from Federal, Hodgdon, Alliant, or a current reloading manual before loading. Begin 10% below listed maximums. Work up in 0.5-grain increments.
Hodgdon Varget is the standard powder for the 338 Federal and has the most published load data. Its temperature stability, consistent performance, and wide availability make it the natural starting point. A Varget load with a 200-grain Nosler Partition is the baseline elk hunting load for the 338 Federal.
IMR 4064 is the classic alternative with similar burn rate and comparable performance. Some barrels show a preference for one or the other – develop both if you have the time, or start with Varget as the more temperature-stable choice.
Practical Hunting Applications
Elk and Large Game
This is the 338 Federal’s primary application and the strongest argument for the cartridge over the 308 Winchester. A 200-grain .338-inch bonded bullet at 2,630 FPS produces deep, reliable penetration through the heavy bone, thick hide, and dense muscle that protect elk vitals from all but the most capable cartridges. The .338-inch bore’s wider wound channel and heavier bullet weight make an elk more likely to fall in sight, or at least leave a better blood trail, than a comparable 308 Winchester load.
At 300 yards it is delivering 1,635 ft-lbs – adequate for elk with quality bonded bullets. For elk hunters who work in heavy timber where shots are measured in yards rather than hundreds of yards, the 338 Federal’s terminal authority is its genuine practical advantage.
Deer and Black Bear
For deer and bear at typical hunting distances inside 300 yards, the 338 Federal with a 180-200 grain bullet is more than adequate. The extra terminal authority over the 308 Winchester is overkill for deer but provides welcome margin on bears, where shot placement on a charging or spooked animal may not be perfect. For a hunter who pursues both deer and bear in the same season with one rifle, the 338 Federal provides bear-appropriate stopping power without excessive range limitation.
Moose
With a 210-225 grain load at 2,550-2,600 FPS, the 338 Federal is capable on moose inside 200 yards. The .338-inch bore’s deep penetration through the moose’s massive shoulder and chest is the argument for using this cartridge on North America’s largest deer species. Keep shots to broadside or clear quartering-away angles and use the Nosler Partition 210-grain or 225-grain for maximum penetration.
Conclusion
The 338 Federal occupies a specific and useful niche: the terminal authority of a .338-inch bore in a short-action rifle that weighs and handles like a 308 Winchester. For elk and bear hunters who work in heavy cover where shots are inside 300 yards and terminal performance matters more than long-range trajectory, it is a logical and effective choice.
The reloading simplicity – 308 Winchester brass can be used directly, the same shell holder applies, powder selection is familiar – makes it more accessible than its limited factory ammunition availability suggests. A reloader who already works with the 308 Winchester can transition to the 338 Federal with minimal new investment in components.
For related reading, see 338 Federal ballistics, 308 Winchester complete guide, 35 Whelen complete guide, and 338 Winchester Magnum complete guide.
Disclaimer: All load data in this article is for reference purposes only. Verify all charges against current published reloading manuals before loading. 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 308 Winchester heritage section explaining the direct case relationship and its practical implications for reloaders (308 brass can be necked up), corrected the ballistics table to 200-yard zero per site standard, a four-cartridge comparison table placing the 338 Federal in context among short and long-action competitors, a complete powder table with 13 powders and charge weight ranges, expanded bullet selection with 10 bullets, recoil comparison table including the 35 Whelen as the natural long-action competitor, and hunting application guidance by game type.
