Load Specifications
Bullet Manufacturer:Lapua
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:1:13.5
Load data in caliber .340 Weath. Mag. with .338 | 250gr | Lapua Lock Base bullet and 100 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Alliant Reloder-26, Accurate High Country and ReloadSwiss RS 70.
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% | 56,173 psi | 88% | 2552 fps | 100% |
| Accurate 2700 | <<locked>> | 84% | 57,130 psi | 90% | 2631 fps | 99.6% |
| Accurate 3100ᴾ | <<locked>> | 100% | 54,984 psi | 86% | 2680 fps | 100% |
| Accurate 4064 | <<locked>> | 84% | 56,666 psi | 89% | 2608 fps | 100% |
| Accurate 4350 | <<locked>> | 92% | 57,479 psi | 90% | 2723 fps | 100% |
| Accurate High Country | <<locked>> | 98% | 56,188 psi | 88% | 2825 fps | 98.9% |
| Accurate MAGPROᴾ | <<locked>> | 100% | 57,145 psi | 90% | 2825 fps | 97.9% |
| ADI AR 2208 | <<locked>> | 86% | 56,434 psi | 88% | 2641 fps | 100% |
| ADI AR 2209 | <<locked>> | 96% | 54,650 psi | 86% | 2723 fps | 99.1% |
| ADI AR 2213ᴾ | <<locked>> | 100% | 55,724 psi | 87% | 2772 fps | 98.5% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 35,882 psi | 56% | 2461 fps | 96.8% |
| Alliant Power Pro 2000-MR | <<locked>> | 82% | 55,927 psi | 88% | 2762 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 96% | 54,752 psi | 86% | 2717 fps | 99.2% |
| Alliant Power Pro Varmint | <<locked>> | 96% | 54,752 psi | 86% | 2717 fps | 99.2% |
| Alliant Reloder- TS 15.5 | <<locked>> | 86% | 57,334 psi | 90% | 2661 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 84% | 57,522 psi | 90% | 2684 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 92% | 54,505 psi | 85% | 2723 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 88% | 55,622 psi | 87% | 2743 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 98% | 57,537 psi | 90% | 2762 fps | 99.4% |
| Alliant Reloder-22ᴾ | <<locked>> | 100% | 54,708 psi | 86% | 2769 fps | 99.3% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 51,721 psi | 81% | 2694 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 44,976 psi | 70% | 2641 fps | 99.9% |
| Alliant Reloder-26 | <<locked>> | 98% | 55,564 psi | 87% | 2831 fps | 100% |
| Bofors RP15ᴾ | <<locked>> | 100% | 50,227 psi | 79% | 2697 fps | 98.7% |
| Bofors RP3 | <<locked>> | 84% | 54,795 psi | 86% | 2631 fps | 100% |
| Bofors RP30ᴾ | <<locked>> | 100% | 40,785 psi | 64% | 2566 fps | 96% |
| Bofors RP5ᴾ | <<locked>> | 100% | 54,708 psi | 86% | 2769 fps | 99.3% |
| Bofors RP7 | <<locked>> | 90% | 57,566 psi | 90% | 2674 fps | 99.8% |
| Hodgdon H1000ᴾ | <<locked>> | 100% | 44,657 psi | 70% | 2582 fps | 97% |
| Hodgdon H380 | <<locked>> | 84% | 55,027 psi | 86% | 2651 fps | 100% |
| Hodgdon H414 | <<locked>> | 90% | 55,854 psi | 88% | 2726 fps | 99.9% |
| Hodgdon H4350 | <<locked>> | 88% | 55,608 psi | 87% | 2684 fps | 99.4% |
| Hodgdon H4831 | <<locked>> | 98% | 55,898 psi | 88% | 2717 fps | 97.9% |
| Hodgdon H4831 SC | <<locked>> | 98% | 54,752 psi | 86% | 2700 fps | 97.7% |
| Hodgdon Hybrid 100V | <<locked>> | 94% | 54,665 psi | 86% | 2648 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 82% | 56,449 psi | 88% | 2680 fps | 100% |
| Hodgdon Retumboᴾ | <<locked>> | 100% | 44,077 psi | 69% | 2680 fps | 98.4% |
| Hodgdon Superformance | <<locked>> | 90% | 56,028 psi | 88% | 2766 fps | 99.8% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,506 psi | 57% | 1617 fps | 100% |
| Hodgdon VARGET | <<locked>> | 82% | 56,811 psi | 89% | 2641 fps | 100% |
| IMR 4064 | <<locked>> | 84% | 56,014 psi | 88% | 2625 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 82% | 55,042 psi | 86% | 2615 fps | 99.8% |
| IMR 4350 | <<locked>> | 92% | 54,998 psi | 86% | 2661 fps | 99.6% |
| IMR 4451 Enduron | <<locked>> | 88% | 55,695 psi | 87% | 2651 fps | 99.8% |
| IMR 4831 | <<locked>> | 94% | 57,696 psi | 90% | 2710 fps | 100% |
| IMR 4895 | <<locked>> | 82% | 55,637 psi | 87% | 2664 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 98% | 57,406 psi | 90% | 2700 fps | 98.2% |
| IMR 7828 SSCᴾ | <<locked>> | 100% | 53,185 psi | 83% | 2746 fps | 98.2% |
| Lovex S060 | <<locked>> | 82% | 57,464 psi | 90% | 2605 fps | 100% |
| Lovex S062 | <<locked>> | 84% | 56,202 psi | 88% | 2615 fps | 100% |
| Lovex S065 | <<locked>> | 90% | 55,898 psi | 88% | 2648 fps | 100% |
| Lovex S070 | <<locked>> | 92% | 57,130 psi | 90% | 2687 fps | 99.9% |
| Lovex S071ᴾ | <<locked>> | 100% | 45,832 psi | 72% | 2549 fps | 99.5% |
| Norma 201 | <<locked>> | 82% | 57,421 psi | 90% | 2621 fps | 100% |
| Norma 203B | <<locked>> | 84% | 56,797 psi | 89% | 2667 fps | 100% |
| Norma 204 | <<locked>> | 92% | 55,753 psi | 87% | 2713 fps | 99.1% |
| Norma MRP | <<locked>> | 98% | 54,230 psi | 85% | 2792 fps | 99.9% |
| Norma URP | <<locked>> | 92% | 55,970 psi | 88% | 2707 fps | 100% |
| Ramshot Big Game | <<locked>> | 82% | 54,027 psi | 85% | 2651 fps | 100% |
| Ramshot Grandᴾ | <<locked>> | 100% | 53,548 psi | 84% | 2762 fps | 98.5% |
| Ramshot Hunter | <<locked>> | 92% | 54,752 psi | 86% | 2713 fps | 100% |
| Ramshot Magnumᴾ | <<locked>> | 100% | 47,659 psi | 75% | 2644 fps | 98.9% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 37,362 psi | 59% | 1660 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 84% | 54,853 psi | 86% | 2638 fps | 99.9% |
| ReloadSwiss RS 60 | <<locked>> | 86% | 55,230 psi | 87% | 2733 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 92% | 57,246 psi | 90% | 2746 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 92% | 55,695 psi | 87% | 2776 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 43,888 psi | 69% | 2674 fps | 99.1% |
| Rottweil R 902 | <<locked>> | 82% | 54,752 psi | 86% | 2579 fps | 100% |
| Rottweil R 903 | <<locked>> | 86% | 54,853 psi | 86% | 2628 fps | 100% |
| Rottweil R 904 | <<locked>> | 96% | 56,260 psi | 88% | 2690 fps | 98.5% |
| Rottweil R 905 | <<locked>> | 98% | 56,826 psi | 89% | 2749 fps | 99.5% |
| Rottweil R 907 | <<locked>> | 90% | 57,566 psi | 90% | 2674 fps | 99.8% |
| Shooters World Long Rifle | <<locked>> | 90% | 55,898 psi | 88% | 2648 fps | 100% |
| Shooters World Precision | <<locked>> | 84% | 56,202 psi | 88% | 2615 fps | 100% |
| Shooters World SW4350 | <<locked>> | 92% | 57,130 psi | 90% | 2687 fps | 99.9% |
| SNPE Vectan SP 11 | <<locked>> | 86% | 56,420 psi | 88% | 2687 fps | 100% |
| SNPE Vectan SP 9 | <<locked>> | 82% | 57,319 psi | 90% | 2657 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 86% | 55,695 psi | 87% | 2513 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 90% | 55,463 psi | 87% | 2605 fps | 99.8% |
| SNPE Vectan Tubal 8000 | <<locked>> | 98% | 56,333 psi | 88% | 2743 fps | 99.4% |
| Somchem S355 | <<locked>> | 86% | 54,708 psi | 86% | 2625 fps | 100% |
| Somchem S361 | <<locked>> | 94% | 54,244 psi | 85% | 2635 fps | 97.5% |
| Somchem S365 | <<locked>> | 94% | 55,434 psi | 87% | 2707 fps | 100% |
| Somchem S385 | <<locked>> | 98% | 57,392 psi | 90% | 2723 fps | 99.8% |
| Vihtavuori N135 | <<locked>> | 82% | 55,201 psi | 87% | 2536 fps | 100% |
| Vihtavuori N140 | <<locked>> | 82% | 55,419 psi | 87% | 2556 fps | 100% |
| Vihtavuori N150 | <<locked>> | 88% | 56,101 psi | 88% | 2598 fps | 100% |
| Vihtavuori N160 | <<locked>> | 90% | 54,505 psi | 85% | 2651 fps | 100% |
| Vihtavuori N165ᴾ | <<locked>> | 100% | 52,939 psi | 83% | 2648 fps | 99.3% |
| Vihtavuori N540 | <<locked>> | 84% | 56,942 psi | 89% | 2598 fps | 100% |
| Vihtavuori N550 | <<locked>> | 92% | 57,203 psi | 90% | 2707 fps | 100% |
| Vihtavuori N555 | <<locked>> | 98% | 54,317 psi | 85% | 2717 fps | 100% |
| Vihtavuori N560 | <<locked>> | 98% | 54,505 psi | 85% | 2782 fps | 98.1% |
| Vihtavuori N565ᴾ | <<locked>> | 100% | 46,586 psi | 73% | 2648 fps | 96.8% |
| Winchester 6.5 StaBALL | <<locked>> | 92% | 57,595 psi | 90% | 2664 fps | 100% |
| Winchester 760 | <<locked>> | 90% | 55,854 psi | 88% | 2726 fps | 99.9% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 46,731 psi | 73% | 2762 fps | 100% |
| Winchester StaBALL Match | <<locked>> | 82% | 57,522 psi | 90% | 2664 fps | 100% |
| Winchester Supreme 780ᴾ | <<locked>> | 100% | 57,740 psi | 90% | 2720 fps | 99.4% |
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% | 52,808 psi | 83% | 2510 fps | 100% |
| Accurate 2700 | <<locked>> | 80% | 50,212 psi | 79% | 2530 fps | 99% |
| Accurate 3100 | <<locked>> | 82% | 30,168 psi | 47% | 2234 fps | 95.8% |
| Accurate 4064 | <<locked>> | 80% | 50,082 psi | 78% | 2520 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 38,319 psi | 60% | 2421 fps | 99.4% |
| Accurate High Country | 72.9 gr | 88% | 39,871 psi | 62% | 2546 fps | 95.3% |
| Accurate MAGPRO | <<locked>> | 94% | 46,354 psi | 73% | 2654 fps | 95.7% |
| ADI AR 2208 | <<locked>> | 80% | 47,036 psi | 74% | 2503 fps | 100% |
| ADI AR 2209 | <<locked>> | 84% | 37,043 psi | 58% | 2405 fps | 95.2% |
| ADI AR 2213 | <<locked>> | 92% | 42,815 psi | 67% | 2549 fps | 95.6% |
| ADI AR 2225 | <<locked>> | 98% | 33,721 psi | 53% | 2405 fps | 95.8% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 52,098 psi | 82% | 2707 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 84% | 37,115 psi | 58% | 2405 fps | 95.4% |
| Alliant Power Pro Varmint | <<locked>> | 84% | 37,115 psi | 58% | 2405 fps | 95.4% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 47,572 psi | 75% | 2526 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 80% | 50,865 psi | 80% | 2592 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 80% | 37,188 psi | 58% | 2431 fps | 99.5% |
| Alliant Reloder-17 | <<locked>> | 80% | 42,177 psi | 66% | 2543 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 84% | 36,753 psi | 58% | 2402 fps | 95.3% |
| Alliant Reloder-22 | <<locked>> | 88% | 36,912 psi | 58% | 2451 fps | 95.5% |
| Alliant Reloder-23 | <<locked>> | 80% | 27,354 psi | 43% | 2215 fps | 98.2% |
| Alliant Reloder-25 | <<locked>> | 86% | 29,080 psi | 46% | 2274 fps | 95.7% |
| Alliant Reloder-26 | 68.2 gr | 80% | 29,037 psi | 46% | 2320 fps | 96.7% |
| Bofors RP15 | <<locked>> | 90% | 36,434 psi | 57% | 2438 fps | 95.2% |
| Bofors RP3 | <<locked>> | 80% | 48,095 psi | 75% | 2539 fps | 100% |
| Bofors RP30 | <<locked>> | 98% | 38,406 psi | 60% | 2516 fps | 95.2% |
| Bofors RP5 | <<locked>> | 88% | 36,912 psi | 58% | 2451 fps | 95.5% |
| Bofors RP7 | <<locked>> | 80% | 42,206 psi | 66% | 2428 fps | 97.8% |
| Hodgdon H1000 | <<locked>> | 96% | 39,146 psi | 61% | 2470 fps | 95.1% |
| Hodgdon H380 | <<locked>> | 80% | 48,399 psi | 76% | 2552 fps | 100% |
| Hodgdon H414 | <<locked>> | 80% | 40,118 psi | 63% | 2464 fps | 98% |
| Hodgdon H4350 | <<locked>> | 80% | 43,134 psi | 68% | 2480 fps | 97.4% |
| Hodgdon H4831 | <<locked>> | 92% | 45,847 psi | 72% | 2556 fps | 95.8% |
| Hodgdon H4831 SC | <<locked>> | 92% | 44,904 psi | 70% | 2543 fps | 95.6% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 34,809 psi | 55% | 2329 fps | 99.8% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 52,707 psi | 83% | 2631 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 94% | 36,448 psi | 57% | 2507 fps | 95.7% |
| Hodgdon Superformance | <<locked>> | 80% | 39,059 psi | 61% | 2480 fps | 97.4% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,369 psi | 43% | 1447 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 53,548 psi | 84% | 2595 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 49,501 psi | 78% | 2533 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 80% | 51,706 psi | 81% | 2562 fps | 99.6% |
| IMR 4350 | <<locked>> | 80% | 37,782 psi | 59% | 2365 fps | 96.7% |
| IMR 4451 Enduron | <<locked>> | 80% | 43,555 psi | 68% | 2454 fps | 98.5% |
| IMR 4831 | <<locked>> | 80% | 36,840 psi | 58% | 2379 fps | 99.2% |
| IMR 4895 | <<locked>> | 80% | 52,185 psi | 82% | 2615 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 90% | 44,846 psi | 70% | 2503 fps | 95.7% |
| IMR 7828 SSC | <<locked>> | 92% | 40,872 psi | 64% | 2526 fps | 95.1% |
| Lovex S060 | <<locked>> | 80% | 53,969 psi | 85% | 2559 fps | 100% |
| Lovex S062 | <<locked>> | 80% | 49,676 psi | 78% | 2526 fps | 100% |
| Lovex S065 | <<locked>> | 80% | 41,147 psi | 64% | 2411 fps | 99% |
| Lovex S070 | <<locked>> | 80% | 39,421 psi | 62% | 2398 fps | 97.9% |
| Lovex S071 | <<locked>> | 86% | 29,385 psi | 46% | 2215 fps | 95.5% |
| Norma 201 | <<locked>> | 80% | 54,128 psi | 85% | 2579 fps | 100% |
| Norma 203B | <<locked>> | 80% | 50,256 psi | 79% | 2579 fps | 100% |
| Norma 204 | <<locked>> | 80% | 37,173 psi | 58% | 2388 fps | 95.2% |
| Norma MRP | <<locked>> | 84% | 33,591 psi | 53% | 2402 fps | 95.8% |
| Norma URP | <<locked>> | 80% | 38,043 psi | 60% | 2415 fps | 99.3% |
| Ramshot Big Game | <<locked>> | 80% | 50,502 psi | 79% | 2598 fps | 100% |
| Ramshot Grand | <<locked>> | 92% | 40,393 psi | 63% | 2530 fps | 95.3% |
| Ramshot Hunter | <<locked>> | 80% | 36,753 psi | 58% | 2405 fps | 97.9% |
| Ramshot Magnum | <<locked>> | 92% | 35,810 psi | 56% | 2415 fps | 95.8% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,876 psi | 44% | 1480 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 48,225 psi | 76% | 2539 fps | 99.5% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 44,831 psi | 70% | 2585 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 37,942 psi | 59% | 2441 fps | 99.2% |
| ReloadSwiss RS 70 | 67.6 gr | 80% | 36,753 psi | 58% | 2448 fps | 98.9% |
| ReloadSwiss RS 76 | <<locked>> | 92% | 33,272 psi | 52% | 2425 fps | 95.5% |
| Rottweil R 902 | <<locked>> | 80% | 51,590 psi | 81% | 2536 fps | 100% |
| Rottweil R 903 | <<locked>> | 80% | 45,281 psi | 71% | 2490 fps | 100% |
| Rottweil R 904 | <<locked>> | 86% | 41,060 psi | 64% | 2438 fps | 95.3% |
| Rottweil R 905 | <<locked>> | 84% | 35,766 psi | 56% | 2382 fps | 95.2% |
| Rottweil R 907 | <<locked>> | 80% | 42,206 psi | 66% | 2428 fps | 97.8% |
| Shooters World Long Rifle | <<locked>> | 80% | 41,147 psi | 64% | 2411 fps | 99% |
| Shooters World Precision | <<locked>> | 80% | 49,676 psi | 78% | 2526 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 39,421 psi | 62% | 2398 fps | 97.9% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 46,253 psi | 72% | 2543 fps | 100% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 53,679 psi | 84% | 2608 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 46,398 psi | 73% | 2392 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 40,219 psi | 63% | 2359 fps | 97.9% |
| SNPE Vectan Tubal 8000 | <<locked>> | 84% | 35,433 psi | 56% | 2379 fps | 95% |
| Somchem S355 | <<locked>> | 80% | 45,513 psi | 71% | 2490 fps | 100% |
| Somchem S361 | <<locked>> | 88% | 44,643 psi | 70% | 2480 fps | 95.4% |
| Somchem S365 | <<locked>> | 80% | 34,447 psi | 54% | 2375 fps | 100% |
| Somchem S385 | <<locked>> | 82% | 34,214 psi | 54% | 2323 fps | 95.5% |
| Vihtavuori N135 | <<locked>> | 80% | 51,880 psi | 81% | 2493 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 52,054 psi | 82% | 2513 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 43,468 psi | 68% | 2421 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 39,465 psi | 62% | 2411 fps | 99.5% |
| Vihtavuori N165 | <<locked>> | 88% | 35,810 psi | 56% | 2352 fps | 95.7% |
| Vihtavuori N540 | <<locked>> | 80% | 50,299 psi | 79% | 2510 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 38,914 psi | 61% | 2418 fps | 99.3% |
| Vihtavuori N555 | <<locked>> | 80% | 30,182 psi | 47% | 2283 fps | 98.2% |
| Vihtavuori N560 | <<locked>> | 90% | 41,727 psi | 65% | 2559 fps | 95% |
| Vihtavuori N565 | <<locked>> | 96% | 40,611 psi | 64% | 2536 fps | 95% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 38,392 psi | 60% | 2382 fps | 100% |
| Winchester 760 | <<locked>> | 80% | 40,263 psi | 63% | 2467 fps | 98% |
| Winchester StaBALL HD | <<locked>> | 80% | 24,105 psi | 38% | 2201 fps | 97.6% |
| Winchester StaBALL Match | <<locked>> | 80% | 53,824 psi | 84% | 2615 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 88% | 38,116 psi | 60% | 2405 fps | 95.7% |
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 100 powders for .340 Weath. Mag. loaded with the .338 | 250gr | Lapua Lock Base. Alliant Reloder-26 delivers the highest muzzle velocity at 2,831 fps; across all powders the maximum-charge window runs from 1,617 fps to 2,831 fps. Accurate 3100 gives the best case fill at 100 %, and 100 of the 100 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (440 MPa), the top charges use 56–90 %, leaving at least 10 % headroom. The 250.0 gr projectile in 0.338" calls for a 1:13.5 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, Accurate High Country, ReloadSwiss RS 70 rank at the top here: for .340 Weath. Mag. with the .338 | 250gr | Lapua Lock Base 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.