Load Specifications
Bullet:.338 | 250gr | Hornady BTHP
Bullet Manufacturer:Hornady
Bullet Weight:250 gr
Bullet Diameter:0.338"
Bullet Length:<<locked>>
Caliber:.340 Weath. Mag. load data
Case Length (l3):2.825"
Cartridge Length (C.O.L.):<<locked>>
Case Capacity:100 Grains of Water
Primer Size:Large Rifle Magnum (LRM)
Barrel Length:26"
Max. allowed Pressure:63,817 psi
Recommended Twist Rate:1:12.5
Load data in caliber .340 Weath. Mag. with .338 | 250gr | Hornady BTHP bullet and 103 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Alliant Reloder-26, ReloadSwiss RS 70 and Hodgdon Superformance.
Important Notice: DO NOT go below Minimum Charge or above Maximum Charge. Since we have no control over the equipment and components used, any responsibility and liability for the results achieved is rejected.
Only powders/loads that match the current filter criteria are displayed: max pressure of a load ≤ 90% of max. standardized pressure, fill rate ≥ 80% and propellant combustion ≥ 95%. Use the sliders above the tables to adjust these thresholds.
Charge: Powder weight in grains. Start with the minimum load and work up carefully.
FR (Fill Rate): Case fill as a percentage. Values above 100% mean compressed loads.
MaxP / %: Maximum chamber pressure in bar and as a percentage of the standardized maximum for this caliber.
V(0): Muzzle velocity in feet per second (fps) at the standardized barrel length.
z (Powder Burn): Estimated propellant combustion percentage at bullet exit.
A valid access license is required to use the Personalized Load Calculator.
You can find more information in our FAQ: How can I use the Personalized Load Calculator?
Max Load - Barrel Length: 26"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2495 | <<locked>> | 82% | 54,839 psi | 86% | 2526 fps | 100% |
| Accurate 2700 | <<locked>> | 84% | 56,028 psi | 88% | 2605 fps | 99.5% |
| Accurate 3100ᴾ | <<locked>> | 100% | 53,301 psi | 84% | 2648 fps | 99.9% |
| Accurate 4064 | <<locked>> | 84% | 55,376 psi | 87% | 2582 fps | 100% |
| Accurate 4350 | <<locked>> | 92% | 55,927 psi | 88% | 2694 fps | 100% |
| Accurate MAGPROᴾ | <<locked>> | 100% | 55,347 psi | 87% | 2789 fps | 97.5% |
| ADI AR 2206H | <<locked>> | 82% | 57,551 psi | 90% | 2654 fps | 100% |
| ADI AR 2208 | <<locked>> | 86% | 55,347 psi | 87% | 2618 fps | 100% |
| ADI AR 2209 | <<locked>> | 98% | 56,666 psi | 89% | 2740 fps | 99.2% |
| ADI AR 2213ᴾ | <<locked>> | 100% | 54,259 psi | 85% | 2736 fps | 98.1% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 34,853 psi | 55% | 2425 fps | 96.1% |
| Alliant Power Pro 2000-MR | <<locked>> | 82% | 54,549 psi | 85% | 2733 fps | 100% |
| Alliant Reloder- TS 15.5 | <<locked>> | 86% | 55,999 psi | 88% | 2635 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 84% | 56,405 psi | 88% | 2661 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 94% | 56,492 psi | 89% | 2743 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 88% | 54,056 psi | 85% | 2717 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 98% | 55,912 psi | 88% | 2730 fps | 99.2% |
| Alliant Reloder-22ᴾ | <<locked>> | 100% | 53,084 psi | 83% | 2736 fps | 99% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 50,227 psi | 79% | 2667 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 43,598 psi | 68% | 2608 fps | 99.8% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 57,508 psi | 90% | 2851 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 82% | 57,464 psi | 90% | 2677 fps | 100% |
| Bofors RP15ᴾ | <<locked>> | 100% | 48,646 psi | 76% | 2664 fps | 98.3% |
| Bofors RP3 | <<locked>> | 86% | 56,855 psi | 89% | 2651 fps | 100% |
| Bofors RP5ᴾ | <<locked>> | 100% | 53,084 psi | 83% | 2736 fps | 99% |
| Bofors RP7 | <<locked>> | 90% | 56,173 psi | 88% | 2644 fps | 99.6% |
| Hodgdon H1000ᴾ | <<locked>> | 100% | 43,424 psi | 68% | 2546 fps | 96.3% |
| Hodgdon H380 | <<locked>> | 86% | 57,421 psi | 90% | 2674 fps | 100% |
| Hodgdon H414 | <<locked>> | 90% | 54,273 psi | 85% | 2694 fps | 99.8% |
| Hodgdon H4350 | <<locked>> | 88% | 54,215 psi | 85% | 2654 fps | 99.1% |
| Hodgdon H4831 | <<locked>> | 98% | 54,360 psi | 85% | 2684 fps | 97.5% |
| Hodgdon H4831 SCᴾ | <<locked>> | 100% | 57,000 psi | 89% | 2720 fps | 97.9% |
| Hodgdon Hybrid 100V | <<locked>> | 96% | 56,710 psi | 89% | 2664 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 82% | 55,027 psi | 86% | 2654 fps | 100% |
| Hodgdon Retumboᴾ | <<locked>> | 100% | 42,801 psi | 67% | 2641 fps | 97.8% |
| Hodgdon Superformance | <<locked>> | 90% | 54,302 psi | 85% | 2733 fps | 99.7% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,535 psi | 57% | 1608 fps | 100% |
| Hodgdon VARGET | <<locked>> | 82% | 55,680 psi | 87% | 2615 fps | 100% |
| IMR 4064 | <<locked>> | 84% | 54,882 psi | 86% | 2598 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 84% | 57,363 psi | 90% | 2635 fps | 99.8% |
| IMR 4350 | <<locked>> | 94% | 57,058 psi | 89% | 2677 fps | 99.7% |
| IMR 4451 Enduron | <<locked>> | 88% | 54,607 psi | 86% | 2625 fps | 99.7% |
| IMR 4831 | <<locked>> | 94% | 56,086 psi | 88% | 2684 fps | 100% |
| IMR 4895 | <<locked>> | 82% | 54,201 psi | 85% | 2635 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 98% | 56,101 psi | 88% | 2671 fps | 97.9% |
| IMR 7828 SSCᴾ | <<locked>> | 100% | 51,692 psi | 81% | 2713 fps | 97.7% |
| Lovex S060 | <<locked>> | 82% | 56,347 psi | 88% | 2582 fps | 100% |
| Lovex S062 | <<locked>> | 84% | 55,013 psi | 86% | 2592 fps | 100% |
| Lovex S065 | <<locked>> | 90% | 54,563 psi | 86% | 2618 fps | 100% |
| Lovex S070 | <<locked>> | 92% | 55,782 psi | 87% | 2661 fps | 99.9% |
| Lovex S071ᴾ | <<locked>> | 100% | 44,353 psi | 70% | 2516 fps | 99.3% |
| Norma 201 | <<locked>> | 82% | 56,217 psi | 88% | 2598 fps | 100% |
| Norma 202 | <<locked>> | 82% | 57,072 psi | 89% | 2592 fps | 100% |
| Norma 203B | <<locked>> | 84% | 55,695 psi | 87% | 2644 fps | 100% |
| Norma 204 | <<locked>> | 92% | 54,273 psi | 85% | 2680 fps | 98.8% |
| Norma MRPᴾ | <<locked>> | 100% | 56,347 psi | 88% | 2812 fps | 99.9% |
| Norma URP | <<locked>> | 92% | 54,534 psi | 85% | 2680 fps | 100% |
| Ramshot Big Game | <<locked>> | 84% | 56,318 psi | 88% | 2671 fps | 100% |
| Ramshot Grandᴾ | <<locked>> | 100% | 51,822 psi | 81% | 2723 fps | 98.1% |
| Ramshot Hunter | <<locked>> | 94% | 56,840 psi | 89% | 2733 fps | 100% |
| Ramshot Magnumᴾ | <<locked>> | 100% | 46,151 psi | 72% | 2608 fps | 98.5% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 37,217 psi | 58% | 1647 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 86% | 57,217 psi | 90% | 2661 fps | 100% |
| ReloadSwiss RS 52 | <<locked>> | 82% | 57,479 psi | 90% | 2723 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 88% | 57,479 psi | 90% | 2753 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 92% | 55,666 psi | 87% | 2720 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 92% | 53,998 psi | 85% | 2746 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 42,453 psi | 67% | 2635 fps | 98.7% |
| Rottweil R 902 | <<locked>> | 84% | 56,942 psi | 89% | 2598 fps | 100% |
| Rottweil R 903 | <<locked>> | 88% | 56,927 psi | 89% | 2648 fps | 100% |
| Rottweil R 904 | <<locked>> | 96% | 54,824 psi | 86% | 2657 fps | 98.2% |
| Rottweil R 905 | <<locked>> | 98% | 55,100 psi | 86% | 2713 fps | 99.2% |
| Rottweil R 907 | <<locked>> | 90% | 56,173 psi | 88% | 2644 fps | 99.6% |
| Shooters World Long Rifle | <<locked>> | 90% | 54,563 psi | 86% | 2618 fps | 100% |
| Shooters World Precision | <<locked>> | 84% | 55,013 psi | 86% | 2592 fps | 100% |
| Shooters World SW4350 | <<locked>> | 92% | 55,782 psi | 87% | 2661 fps | 99.9% |
| SNPE Vectan SP 11 | <<locked>> | 86% | 54,969 psi | 86% | 2661 fps | 100% |
| SNPE Vectan SP 9 | <<locked>> | 82% | 56,043 psi | 88% | 2631 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 82% | 57,174 psi | 90% | 2526 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 86% | 54,563 psi | 86% | 2490 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 92% | 57,711 psi | 90% | 2625 fps | 99.9% |
| SNPE Vectan Tubal 8000 | <<locked>> | 98% | 54,621 psi | 86% | 2710 fps | 99.1% |
| Somchem S335 | <<locked>> | 82% | 56,710 psi | 89% | 2526 fps | 100% |
| Somchem S355 | <<locked>> | 88% | 56,942 psi | 89% | 2644 fps | 100% |
| Somchem S361 | <<locked>> | 96% | 56,536 psi | 89% | 2654 fps | 97.7% |
| Somchem S365 | <<locked>> | 96% | 57,261 psi | 90% | 2723 fps | 100% |
| Somchem S385 | <<locked>> | 98% | 55,709 psi | 87% | 2690 fps | 99.6% |
| Vihtavuori N133 | <<locked>> | 82% | 57,725 psi | 90% | 2507 fps | 100% |
| Vihtavuori N135 | <<locked>> | 84% | 57,319 psi | 90% | 2552 fps | 100% |
| Vihtavuori N140 | <<locked>> | 84% | 57,696 psi | 90% | 2572 fps | 100% |
| Vihtavuori N150 | <<locked>> | 88% | 54,636 psi | 86% | 2572 fps | 100% |
| Vihtavuori N160 | <<locked>> | 92% | 56,753 psi | 89% | 2671 fps | 100% |
| Vihtavuori N165ᴾ | <<locked>> | 100% | 51,387 psi | 81% | 2615 fps | 99% |
| Vihtavuori N540 | <<locked>> | 84% | 55,738 psi | 87% | 2575 fps | 100% |
| Vihtavuori N550 | <<locked>> | 92% | 55,637 psi | 87% | 2677 fps | 100% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 56,115 psi | 88% | 2733 fps | 100% |
| Vihtavuori N560ᴾ | <<locked>> | 100% | 56,681 psi | 89% | 2805 fps | 98.2% |
| Vihtavuori N565ᴾ | <<locked>> | 100% | 44,875 psi | 70% | 2608 fps | 96.1% |
| Winchester 6.5 StaBALL | <<locked>> | 92% | 56,188 psi | 88% | 2638 fps | 100% |
| Winchester 760 | <<locked>> | 90% | 54,491 psi | 85% | 2697 fps | 99.8% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 45,281 psi | 71% | 2730 fps | 100% |
| Winchester StaBALL Match | <<locked>> | 82% | 56,260 psi | 88% | 2641 fps | 100% |
| Winchester Supreme 780ᴾ | <<locked>> | 100% | 55,898 psi | 88% | 2687 fps | 99.1% |
Recommended = one of the top powders for this cartridge and bullet combination.
Start Load - Barrel Length: 26"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2495 | <<locked>> | 80% | 51,459 psi | 81% | 2487 fps | 100% |
| Accurate 2700 | <<locked>> | 80% | 49,240 psi | 77% | 2507 fps | 98.7% |
| Accurate 3100 | <<locked>> | 82% | 29,138 psi | 46% | 2205 fps | 95.2% |
| Accurate 4064 | <<locked>> | 80% | 48,762 psi | 76% | 2497 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 37,202 psi | 58% | 2392 fps | 99.2% |
| Accurate MAGPRO | <<locked>> | 94% | 44,875 psi | 70% | 2618 fps | 95.1% |
| ADI AR 2206H | <<locked>> | 80% | 54,215 psi | 85% | 2608 fps | 100% |
| ADI AR 2208 | <<locked>> | 80% | 46,122 psi | 72% | 2480 fps | 100% |
| ADI AR 2209 | <<locked>> | 86% | 38,595 psi | 60% | 2428 fps | 95.5% |
| ADI AR 2213 | <<locked>> | 94% | 44,512 psi | 70% | 2572 fps | 95.8% |
| ADI AR 2225 | <<locked>> | 98% | 32,721 psi | 51% | 2369 fps | 95% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 50,720 psi | 79% | 2680 fps | 100% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 46,601 psi | 73% | 2503 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 80% | 49,719 psi | 78% | 2566 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 80% | 36,332 psi | 57% | 2402 fps | 99.3% |
| Alliant Reloder-17 | <<locked>> | 80% | 40,988 psi | 64% | 2513 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 86% | 38,159 psi | 60% | 2421 fps | 95.6% |
| Alliant Reloder-22 | <<locked>> | 90% | 38,261 psi | 60% | 2470 fps | 95.8% |
| Alliant Reloder-23 | <<locked>> | 80% | 26,556 psi | 42% | 2185 fps | 97.7% |
| Alliant Reloder-25 | <<locked>> | 86% | 28,311 psi | 44% | 2244 fps | 95% |
| Alliant Reloder-26 | 66.5 gr | 80% | 28,195 psi | 44% | 2287 fps | 96.1% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 53,940 psi | 85% | 2628 fps | 100% |
| Bofors RP15 | <<locked>> | 92% | 37,753 psi | 59% | 2457 fps | 95.5% |
| Bofors RP3 | <<locked>> | 80% | 46,731 psi | 73% | 2510 fps | 100% |
| Bofors RP5 | <<locked>> | 90% | 38,261 psi | 60% | 2470 fps | 95.8% |
| Bofors RP7 | <<locked>> | 80% | 41,220 psi | 65% | 2402 fps | 97.4% |
| Hodgdon H1000 | <<locked>> | 98% | 40,596 psi | 64% | 2487 fps | 95.4% |
| Hodgdon H380 | <<locked>> | 80% | 47,137 psi | 74% | 2526 fps | 99.9% |
| Hodgdon H414 | <<locked>> | 80% | 39,102 psi | 61% | 2434 fps | 97.6% |
| Hodgdon H4350 | <<locked>> | 80% | 41,959 psi | 66% | 2448 fps | 97% |
| Hodgdon H4831 | <<locked>> | 92% | 44,570 psi | 70% | 2523 fps | 95.2% |
| Hodgdon H4831 SC | <<locked>> | 94% | 46,673 psi | 73% | 2562 fps | 95.8% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 33,881 psi | 53% | 2303 fps | 99.6% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 51,358 psi | 80% | 2605 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 96% | 37,724 psi | 59% | 2526 fps | 96% |
| Hodgdon Superformance | 68.6 gr | 80% | 37,927 psi | 59% | 2448 fps | 96.9% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,180 psi | 43% | 1434 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 52,388 psi | 82% | 2572 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 48,530 psi | 76% | 2510 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 80% | 50,705 psi | 79% | 2539 fps | 99.4% |
| IMR 4350 | <<locked>> | 80% | 36,854 psi | 58% | 2336 fps | 96.3% |
| IMR 4451 Enduron | <<locked>> | 80% | 42,598 psi | 67% | 2428 fps | 98.1% |
| IMR 4831 | <<locked>> | 80% | 35,795 psi | 56% | 2349 fps | 99% |
| IMR 4895 | <<locked>> | 80% | 50,995 psi | 80% | 2589 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 90% | 43,729 psi | 69% | 2470 fps | 95.2% |
| IMR 7828 SSC | <<locked>> | 94% | 42,409 psi | 66% | 2546 fps | 95.3% |
| Lovex S060 | <<locked>> | 80% | 53,069 psi | 83% | 2536 fps | 100% |
| Lovex S062 | <<locked>> | 80% | 48,718 psi | 76% | 2503 fps | 100% |
| Lovex S065 | <<locked>> | 80% | 40,176 psi | 63% | 2382 fps | 98.8% |
| Lovex S070 | <<locked>> | 80% | 38,421 psi | 60% | 2369 fps | 97.5% |
| Lovex S071 | <<locked>> | 88% | 30,429 psi | 48% | 2234 fps | 95.8% |
| Norma 201 | <<locked>> | 80% | 52,924 psi | 83% | 2552 fps | 100% |
| Norma 202 | <<locked>> | 80% | 53,679 psi | 84% | 2549 fps | 100% |
| Norma 203B | <<locked>> | 80% | 49,095 psi | 77% | 2552 fps | 100% |
| Norma 204 | <<locked>> | 82% | 38,783 psi | 61% | 2415 fps | 95.5% |
| Norma MRP | <<locked>> | 84% | 32,706 psi | 51% | 2372 fps | 95.2% |
| Norma URP | <<locked>> | 80% | 36,985 psi | 58% | 2385 fps | 99.1% |
| Ramshot Big Game | <<locked>> | 80% | 49,240 psi | 77% | 2572 fps | 100% |
| Ramshot Grand | <<locked>> | 94% | 42,018 psi | 66% | 2549 fps | 95.6% |
| Ramshot Hunter | <<locked>> | 80% | 35,810 psi | 56% | 2379 fps | 97.5% |
| Ramshot Magnum | <<locked>> | 92% | 34,809 psi | 55% | 2385 fps | 95.1% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,862 psi | 44% | 1473 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 47,224 psi | 74% | 2513 fps | 99.3% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 53,722 psi | 84% | 2674 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 43,526 psi | 68% | 2556 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 36,782 psi | 58% | 2408 fps | 98.9% |
| ReloadSwiss RS 70 | 65.9 gr | 80% | 35,781 psi | 56% | 2418 fps | 98.5% |
| ReloadSwiss RS 76 | <<locked>> | 94% | 34,548 psi | 54% | 2451 fps | 95.8% |
| Rottweil R 902 | <<locked>> | 80% | 50,575 psi | 79% | 2513 fps | 100% |
| Rottweil R 903 | <<locked>> | 80% | 44,106 psi | 69% | 2464 fps | 100% |
| Rottweil R 904 | <<locked>> | 88% | 42,627 psi | 67% | 2457 fps | 95.6% |
| Rottweil R 905 | <<locked>> | 86% | 37,173 psi | 58% | 2405 fps | 95.5% |
| Rottweil R 907 | <<locked>> | 80% | 41,220 psi | 65% | 2402 fps | 97.4% |
| Shooters World Long Rifle | <<locked>> | 80% | 40,176 psi | 63% | 2382 fps | 98.8% |
| Shooters World Precision | <<locked>> | 80% | 48,718 psi | 76% | 2503 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 38,421 psi | 60% | 2369 fps | 97.5% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 45,179 psi | 71% | 2516 fps | 100% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 52,620 psi | 82% | 2585 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 53,722 psi | 84% | 2484 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 45,440 psi | 71% | 2369 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 39,305 psi | 62% | 2333 fps | 97.5% |
| SNPE Vectan Tubal 8000 | <<locked>> | 86% | 36,811 psi | 58% | 2402 fps | 95.3% |
| Somchem S335 | <<locked>> | 80% | 53,432 psi | 84% | 2484 fps | 100% |
| Somchem S355 | <<locked>> | 80% | 44,396 psi | 70% | 2464 fps | 100% |
| Somchem S361 | <<locked>> | 90% | 46,514 psi | 73% | 2503 fps | 95.7% |
| Somchem S365 | <<locked>> | 80% | 33,417 psi | 52% | 2349 fps | 100% |
| Somchem S385 | <<locked>> | 84% | 35,476 psi | 56% | 2343 fps | 95.8% |
| Vihtavuori N133 | <<locked>> | 80% | 54,259 psi | 85% | 2467 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 50,734 psi | 80% | 2470 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 50,865 psi | 80% | 2487 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 42,409 psi | 66% | 2398 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 38,421 psi | 60% | 2385 fps | 99.3% |
| Vihtavuori N165 | <<locked>> | 88% | 34,911 psi | 55% | 2323 fps | 95.1% |
| Vihtavuori N540 | <<locked>> | 80% | 49,052 psi | 77% | 2487 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 37,782 psi | 59% | 2385 fps | 99% |
| Vihtavuori N555 | <<locked>> | 80% | 29,269 psi | 46% | 2254 fps | 97.7% |
| Vihtavuori N560 | <<locked>> | 92% | 43,424 psi | 68% | 2582 fps | 95.3% |
| Vihtavuori N565 | <<locked>> | 98% | 42,105 psi | 66% | 2559 fps | 95.3% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 37,449 psi | 59% | 2356 fps | 100% |
| Winchester 760 | <<locked>> | 80% | 39,262 psi | 62% | 2441 fps | 97.6% |
| Winchester StaBALL HD | <<locked>> | 80% | 23,467 psi | 37% | 2165 fps | 96.8% |
| Winchester StaBALL Match | <<locked>> | 80% | 52,518 psi | 82% | 2589 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 88% | 37,072 psi | 58% | 2375 fps | 95.1% |
Recommended = one of the top powders for this cartridge and bullet combination.
ᴾ possible press load - work up slowly to this load while watching for signs of excessive pressure.
This overview compares 103 powders for .340 Weath. Mag. loaded with the .338 | 250gr | Hornady BTHP. Alliant Reloder-26 delivers the highest muzzle velocity at 2,851 fps; across all powders the maximum-charge window runs from 1,608 fps to 2,851 fps. Accurate 3100 gives the best case fill at 100 %, and 103 of the 103 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (440 MPa), the top charges use 55–90 %, leaving at least 10 % headroom. The 250.0 gr projectile in 0.338" calls for a 1:12.5 twist; slower twists will usually not stabilise this weight. Accurate 3100, Accurate MAGPRO, ADI AR 2213 reach 100 % fill or more at maximum charge, so these are compressed loads: they need a long drop tube to seat cleanly and react sensitively to the case capacity of your own brass lot. Alliant Reloder-26, ReloadSwiss RS 70, Hodgdon Superformance rank at the top here: for .340 Weath. Mag. with the .338 | 250gr | Hornady BTHP they combine a high case fill with complete burn and sit in the upper velocity band. Always begin at the start load and work up in small increments while checking case and primer for pressure signs.