Load Specifications
Bullet Manufacturer:Speer
Bullet Weight:225 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:1:6.0
Load data in caliber .340 Weath. Mag. with .338 | 225gr | Speer Grand Slam bullet and 101 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are ReloadSwiss RS 70, Alliant Reloder-26 and Accurate High Country.
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% | 55,027 psi | 86% | 2697 fps | 100% |
| Accurate 2700 | <<locked>> | 84% | 56,188 psi | 88% | 2776 fps | 99.2% |
| Accurate 3100ᴾ | <<locked>> | 100% | 53,998 psi | 85% | 2822 fps | 99.8% |
| Accurate 4064 | <<locked>> | 84% | 55,550 psi | 87% | 2756 fps | 100% |
| Accurate 4350 | <<locked>> | 92% | 56,246 psi | 88% | 2867 fps | 100% |
| Accurate High Country | <<locked>> | 98% | 55,085 psi | 86% | 2966 fps | 98.1% |
| Accurate MAGPROᴾ | <<locked>> | 100% | 55,985 psi | 88% | 2963 fps | 97% |
| ADI AR 2206H | <<locked>> | 82% | 57,740 psi | 90% | 2828 fps | 100% |
| ADI AR 2208 | <<locked>> | 86% | 55,535 psi | 87% | 2789 fps | 100% |
| ADI AR 2209 | <<locked>> | 98% | 57,058 psi | 89% | 2913 fps | 98.9% |
| ADI AR 2213ᴾ | <<locked>> | 100% | 54,723 psi | 86% | 2910 fps | 97.6% |
| Alliant Power Pro 2000-MR | <<locked>> | 82% | 54,810 psi | 86% | 2913 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 98% | 57,174 psi | 90% | 2910 fps | 99% |
| Alliant Power Pro Varmint | <<locked>> | 98% | 57,174 psi | 90% | 2910 fps | 99% |
| Alliant Reloder- TS 15.5 | <<locked>> | 86% | 56,231 psi | 88% | 2808 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 84% | 56,492 psi | 89% | 2831 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 94% | 56,826 psi | 89% | 2920 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 88% | 54,549 psi | 85% | 2894 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 98% | 56,420 psi | 88% | 2900 fps | 98.9% |
| Alliant Reloder-22ᴾ | <<locked>> | 100% | 53,592 psi | 84% | 2907 fps | 98.7% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 50,517 psi | 79% | 2835 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 44,048 psi | 69% | 2769 fps | 99.5% |
| Alliant Reloder-26 | <<locked>> | 98% | 54,230 psi | 85% | 2976 fps | 100% |
| Bofors RP15ᴾ | <<locked>> | 100% | 49,037 psi | 77% | 2828 fps | 97.8% |
| Bofors RP3 | <<locked>> | 86% | 57,217 psi | 90% | 2828 fps | 100% |
| Bofors RP5ᴾ | <<locked>> | 100% | 53,592 psi | 84% | 2907 fps | 98.7% |
| Bofors RP7 | <<locked>> | 90% | 56,521 psi | 89% | 2818 fps | 99.4% |
| Hodgdon H380 | <<locked>> | 86% | 57,595 psi | 90% | 2848 fps | 100% |
| Hodgdon H414 | <<locked>> | 90% | 54,723 psi | 86% | 2867 fps | 99.6% |
| Hodgdon H4350 | <<locked>> | 88% | 54,491 psi | 85% | 2825 fps | 98.8% |
| Hodgdon H4831 | <<locked>> | 98% | 54,795 psi | 86% | 2851 fps | 97% |
| Hodgdon H4831 SCᴾ | <<locked>> | 100% | 57,493 psi | 90% | 2894 fps | 97.5% |
| Hodgdon Hybrid 100V | <<locked>> | 96% | 57,087 psi | 89% | 2838 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 82% | 55,129 psi | 86% | 2828 fps | 100% |
| Hodgdon Retumboᴾ | <<locked>> | 100% | 43,105 psi | 68% | 2799 fps | 97.2% |
| Hodgdon Superformance | <<locked>> | 90% | 54,781 psi | 86% | 2904 fps | 99.5% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,448 psi | 57% | 1732 fps | 100% |
| Hodgdon VARGET | <<locked>> | 82% | 55,883 psi | 88% | 2789 fps | 100% |
| IMR 4064 | <<locked>> | 84% | 55,100 psi | 86% | 2772 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 84% | 57,566 psi | 90% | 2808 fps | 99.7% |
| IMR 4350 | <<locked>> | 94% | 57,522 psi | 90% | 2851 fps | 99.5% |
| IMR 4451 Enduron | <<locked>> | 88% | 54,650 psi | 86% | 2792 fps | 99.4% |
| IMR 4831 | <<locked>> | 94% | 56,594 psi | 89% | 2858 fps | 100% |
| IMR 4895 | <<locked>> | 82% | 54,404 psi | 85% | 2808 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 98% | 56,449 psi | 88% | 2841 fps | 97.4% |
| IMR 7828 SSCᴾ | <<locked>> | 100% | 52,054 psi | 82% | 2881 fps | 97.2% |
| Lovex S060 | <<locked>> | 82% | 56,565 psi | 89% | 2756 fps | 100% |
| Lovex S062 | <<locked>> | 84% | 55,216 psi | 87% | 2766 fps | 100% |
| Lovex S065 | <<locked>> | 90% | 54,897 psi | 86% | 2789 fps | 99.9% |
| Lovex S070 | <<locked>> | 92% | 56,188 psi | 88% | 2831 fps | 99.7% |
| Lovex S071ᴾ | <<locked>> | 100% | 44,875 psi | 70% | 2677 fps | 99% |
| Norma 201 | <<locked>> | 82% | 56,434 psi | 88% | 2772 fps | 100% |
| Norma 202 | <<locked>> | 82% | 57,188 psi | 90% | 2766 fps | 100% |
| Norma 203B | <<locked>> | 84% | 55,782 psi | 87% | 2818 fps | 100% |
| Norma 204 | <<locked>> | 92% | 54,534 psi | 85% | 2848 fps | 98.5% |
| Norma MRPᴾ | <<locked>> | 100% | 56,869 psi | 89% | 2989 fps | 99.8% |
| Norma URP | <<locked>> | 92% | 54,911 psi | 86% | 2854 fps | 100% |
| Ramshot Big Game | <<locked>> | 84% | 56,724 psi | 89% | 2848 fps | 100% |
| Ramshot Grandᴾ | <<locked>> | 100% | 52,388 psi | 82% | 2897 fps | 97.6% |
| Ramshot Hunter | <<locked>> | 94% | 57,246 psi | 90% | 2907 fps | 100% |
| Ramshot Magnumᴾ | <<locked>> | 100% | 46,804 psi | 73% | 2772 fps | 98.1% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 37,043 psi | 58% | 1772 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 86% | 57,624 psi | 90% | 2835 fps | 99.9% |
| ReloadSwiss RS 52 | <<locked>> | 82% | 57,696 psi | 90% | 2904 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 86% | 54,027 psi | 85% | 2884 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 92% | 55,985 psi | 88% | 2890 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 92% | 54,491 psi | 85% | 2920 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 42,989 psi | 67% | 2792 fps | 98.2% |
| Rottweil R 902 | <<locked>> | 84% | 57,232 psi | 90% | 2776 fps | 100% |
| Rottweil R 903 | <<locked>> | 88% | 57,276 psi | 90% | 2822 fps | 100% |
| Rottweil R 904 | <<locked>> | 96% | 55,143 psi | 86% | 2828 fps | 97.7% |
| Rottweil R 905 | <<locked>> | 98% | 55,492 psi | 87% | 2884 fps | 98.9% |
| Rottweil R 907 | <<locked>> | 90% | 56,521 psi | 89% | 2818 fps | 99.4% |
| Shooters World Long Rifle | <<locked>> | 90% | 54,897 psi | 86% | 2789 fps | 99.9% |
| Shooters World Precision | <<locked>> | 84% | 55,216 psi | 87% | 2766 fps | 100% |
| Shooters World SW4350 | <<locked>> | 92% | 56,188 psi | 88% | 2831 fps | 99.7% |
| SNPE Vectan SP 11 | <<locked>> | 86% | 55,230 psi | 87% | 2831 fps | 100% |
| SNPE Vectan SP 9 | <<locked>> | 82% | 56,260 psi | 88% | 2805 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 82% | 57,319 psi | 90% | 2700 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 86% | 54,839 psi | 86% | 2661 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 90% | 54,505 psi | 85% | 2743 fps | 99.5% |
| SNPE Vectan Tubal 8000 | <<locked>> | 98% | 54,998 psi | 86% | 2881 fps | 98.8% |
| Somchem S335 | <<locked>> | 82% | 56,869 psi | 89% | 2697 fps | 100% |
| Somchem S355 | <<locked>> | 88% | 57,159 psi | 90% | 2818 fps | 100% |
| Somchem S361 | <<locked>> | 96% | 57,058 psi | 89% | 2822 fps | 97.3% |
| Somchem S365 | <<locked>> | 94% | 54,201 psi | 85% | 2854 fps | 100% |
| Somchem S385 | <<locked>> | 98% | 56,304 psi | 88% | 2864 fps | 99.4% |
| Vihtavuori N135 | <<locked>> | 84% | 57,696 psi | 90% | 2730 fps | 100% |
| Vihtavuori N140 | <<locked>> | 82% | 54,360 psi | 85% | 2700 fps | 100% |
| Vihtavuori N150 | <<locked>> | 88% | 54,969 psi | 86% | 2743 fps | 100% |
| Vihtavuori N160 | <<locked>> | 92% | 56,956 psi | 89% | 2844 fps | 100% |
| Vihtavuori N165ᴾ | <<locked>> | 100% | 51,996 psi | 81% | 2785 fps | 98.7% |
| Vihtavuori N540 | <<locked>> | 84% | 55,999 psi | 88% | 2746 fps | 100% |
| Vihtavuori N550 | <<locked>> | 92% | 56,072 psi | 88% | 2851 fps | 100% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 56,623 psi | 89% | 2910 fps | 100% |
| Vihtavuori N560ᴾ | <<locked>> | 100% | 57,145 psi | 90% | 2979 fps | 97.8% |
| Winchester 6.5 StaBALL | <<locked>> | 92% | 56,565 psi | 89% | 2812 fps | 100% |
| Winchester 760 | <<locked>> | 90% | 54,926 psi | 86% | 2871 fps | 99.6% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 45,687 psi | 72% | 2900 fps | 100% |
| Winchester StaBALL Match | <<locked>> | 82% | 56,434 psi | 88% | 2812 fps | 100% |
| Winchester Supreme 780ᴾ | <<locked>> | 100% | 56,478 psi | 89% | 2858 fps | 98.8% |
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% | 51,735 psi | 81% | 2654 fps | 100% |
| Accurate 2700 | <<locked>> | 80% | 49,371 psi | 77% | 2667 fps | 98.3% |
| Accurate 3100 | <<locked>> | 84% | 31,328 psi | 49% | 2388 fps | 95.3% |
| Accurate 4064 | <<locked>> | 80% | 49,008 psi | 77% | 2664 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 37,420 psi | 59% | 2543 fps | 98.8% |
| Accurate High Country | 81.2 gr | 92% | 44,672 psi | 70% | 2782 fps | 95.8% |
| Accurate MAGPRO | <<locked>> | 96% | 48,588 psi | 76% | 2841 fps | 95.3% |
| ADI AR 2206H | <<locked>> | 80% | 54,404 psi | 85% | 2782 fps | 100% |
| ADI AR 2208 | <<locked>> | 80% | 46,238 psi | 72% | 2641 fps | 100% |
| ADI AR 2209 | <<locked>> | 88% | 41,263 psi | 65% | 2635 fps | 95.6% |
| ADI AR 2213 | <<locked>> | 94% | 44,875 psi | 70% | 2730 fps | 95.2% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 51,082 psi | 80% | 2854 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 88% | 41,365 psi | 65% | 2635 fps | 95.8% |
| Alliant Power Pro Varmint | <<locked>> | 88% | 41,365 psi | 65% | 2635 fps | 95.8% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 46,601 psi | 73% | 2664 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 80% | 49,937 psi | 78% | 2733 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 80% | 36,419 psi | 57% | 2552 fps | 98.9% |
| Alliant Reloder-17 | <<locked>> | 80% | 41,249 psi | 65% | 2674 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 88% | 40,915 psi | 64% | 2628 fps | 95.7% |
| Alliant Reloder-22 | <<locked>> | 90% | 38,435 psi | 60% | 2618 fps | 95% |
| Alliant Reloder-23 | <<locked>> | 80% | 26,731 psi | 42% | 2316 fps | 96.9% |
| Alliant Reloder-25 | <<locked>> | 88% | 30,211 psi | 47% | 2431 fps | 95% |
| Alliant Reloder-26 | 72.7 gr | 80% | 28,340 psi | 44% | 2421 fps | 95.1% |
| Bofors RP15 | <<locked>> | 94% | 40,437 psi | 63% | 2661 fps | 95.6% |
| Bofors RP3 | <<locked>> | 80% | 47,036 psi | 74% | 2677 fps | 100% |
| Bofors RP5 | <<locked>> | 90% | 38,435 psi | 60% | 2618 fps | 95% |
| Bofors RP7 | <<locked>> | 80% | 41,394 psi | 65% | 2552 fps | 96.9% |
| Hodgdon H380 | <<locked>> | 80% | 47,326 psi | 74% | 2690 fps | 99.8% |
| Hodgdon H414 | <<locked>> | 80% | 39,204 psi | 61% | 2585 fps | 96.9% |
| Hodgdon H4350 | <<locked>> | 80% | 42,250 psi | 66% | 2608 fps | 96.4% |
| Hodgdon H4831 | <<locked>> | 94% | 48,022 psi | 75% | 2740 fps | 95.4% |
| Hodgdon H4831 SC | <<locked>> | 94% | 47,108 psi | 74% | 2723 fps | 95.2% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 33,881 psi | 53% | 2444 fps | 99.3% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 51,692 psi | 81% | 2779 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 96% | 37,913 psi | 59% | 2674 fps | 95.1% |
| Hodgdon Superformance | <<locked>> | 80% | 38,145 psi | 60% | 2595 fps | 96.2% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,253 psi | 43% | 1545 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 52,446 psi | 82% | 2740 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 48,646 psi | 76% | 2674 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 80% | 50,792 psi | 80% | 2703 fps | 99.1% |
| IMR 4350 | <<locked>> | 80% | 37,086 psi | 58% | 2484 fps | 95.6% |
| IMR 4451 Enduron | <<locked>> | 80% | 42,714 psi | 67% | 2582 fps | 97.6% |
| IMR 4831 | <<locked>> | 80% | 35,868 psi | 56% | 2493 fps | 98.5% |
| IMR 4895 | <<locked>> | 80% | 51,227 psi | 80% | 2762 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 92% | 46,905 psi | 74% | 2684 fps | 95.4% |
| IMR 7828 SSC | <<locked>> | 96% | 45,571 psi | 71% | 2759 fps | 95.5% |
| Lovex S060 | <<locked>> | 80% | 53,171 psi | 83% | 2707 fps | 100% |
| Lovex S062 | <<locked>> | 80% | 48,820 psi | 77% | 2667 fps | 100% |
| Lovex S065 | <<locked>> | 80% | 40,350 psi | 63% | 2536 fps | 98.3% |
| Lovex S070 | <<locked>> | 80% | 38,551 psi | 60% | 2516 fps | 96.9% |
| Lovex S071 | <<locked>> | 90% | 32,605 psi | 51% | 2421 fps | 95.8% |
| Norma 201 | <<locked>> | 80% | 53,185 psi | 83% | 2726 fps | 100% |
| Norma 202 | <<locked>> | 80% | 53,679 psi | 84% | 2720 fps | 100% |
| Norma 203B | <<locked>> | 80% | 49,298 psi | 77% | 2720 fps | 100% |
| Norma 204 | <<locked>> | 84% | 41,771 psi | 65% | 2625 fps | 95.7% |
| Norma MRP | <<locked>> | 86% | 35,215 psi | 55% | 2575 fps | 95.4% |
| Norma URP | <<locked>> | 80% | 37,101 psi | 58% | 2536 fps | 98.6% |
| Ramshot Big Game | <<locked>> | 80% | 49,588 psi | 78% | 2743 fps | 100% |
| Ramshot Grand | <<locked>> | 96% | 45,484 psi | 71% | 2769 fps | 95.9% |
| Ramshot Hunter | <<locked>> | 80% | 36,013 psi | 56% | 2523 fps | 96.8% |
| Ramshot Magnum | <<locked>> | 94% | 37,652 psi | 59% | 2589 fps | 95.4% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,688 psi | 43% | 1585 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 47,427 psi | 74% | 2674 fps | 99% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 53,983 psi | 85% | 2848 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 43,830 psi | 69% | 2723 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 37,028 psi | 58% | 2559 fps | 98.5% |
| ReloadSwiss RS 70 | 72.1 gr | 80% | 36,027 psi | 56% | 2566 fps | 97.9% |
| ReloadSwiss RS 76 | <<locked>> | 96% | 37,463 psi | 59% | 2661 fps | 96.2% |
| Rottweil R 902 | <<locked>> | 80% | 50,589 psi | 79% | 2677 fps | 100% |
| Rottweil R 903 | <<locked>> | 80% | 44,237 psi | 69% | 2625 fps | 100% |
| Rottweil R 904 | <<locked>> | 90% | 45,614 psi | 71% | 2667 fps | 95.7% |
| Rottweil R 905 | <<locked>> | 88% | 40,030 psi | 63% | 2612 fps | 95.6% |
| Rottweil R 907 | <<locked>> | 80% | 41,394 psi | 65% | 2552 fps | 96.9% |
| Shooters World Long Rifle | <<locked>> | 80% | 40,350 psi | 63% | 2536 fps | 98.3% |
| Shooters World Precision | <<locked>> | 80% | 48,820 psi | 77% | 2667 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 38,551 psi | 60% | 2516 fps | 96.9% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 45,440 psi | 71% | 2680 fps | 100% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 52,852 psi | 83% | 2756 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 53,954 psi | 85% | 2654 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 45,629 psi | 72% | 2530 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 39,479 psi | 62% | 2480 fps | 97% |
| SNPE Vectan Tubal 8000 | <<locked>> | 88% | 39,653 psi | 62% | 2605 fps | 95.5% |
| Somchem S335 | <<locked>> | 80% | 53,664 psi | 84% | 2654 fps | 100% |
| Somchem S355 | <<locked>> | 80% | 44,628 psi | 70% | 2625 fps | 100% |
| Somchem S361 | <<locked>> | 90% | 46,760 psi | 73% | 2657 fps | 95% |
| Somchem S365 | <<locked>> | 80% | 33,620 psi | 53% | 2497 fps | 99.9% |
| Somchem S385 | <<locked>> | 84% | 35,636 psi | 56% | 2487 fps | 95% |
| Vihtavuori N135 | <<locked>> | 80% | 50,966 psi | 80% | 2641 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 50,995 psi | 80% | 2654 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 42,554 psi | 67% | 2556 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 38,595 psi | 60% | 2536 fps | 98.9% |
| Vihtavuori N165 | <<locked>> | 90% | 37,376 psi | 59% | 2520 fps | 95.2% |
| Vihtavuori N540 | <<locked>> | 80% | 49,255 psi | 77% | 2651 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 37,956 psi | 59% | 2536 fps | 98.6% |
| Vihtavuori N555 | <<locked>> | 80% | 29,341 psi | 46% | 2388 fps | 97% |
| Vihtavuori N560 | <<locked>> | 94% | 46,615 psi | 73% | 2799 fps | 95.5% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 37,623 psi | 59% | 2507 fps | 99.9% |
| Winchester 760 | <<locked>> | 80% | 39,378 psi | 62% | 2589 fps | 97% |
| Winchester StaBALL HD | <<locked>> | 80% | 23,598 psi | 37% | 2287 fps | 95.5% |
| Winchester StaBALL Match | <<locked>> | 80% | 52,794 psi | 83% | 2759 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 90% | 39,900 psi | 63% | 2575 fps | 95.3% |
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 101 powders for .340 Weath. Mag. loaded with the .338 | 225gr | Speer Grand Slam. Norma MRP delivers the highest muzzle velocity at 2,989 fps; across all powders the maximum-charge window runs from 1,732 fps to 2,989 fps. Accurate 3100 gives the best case fill at 100 %, and 101 of the 101 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (440 MPa), the top charges use 57–90 %, leaving at least 10 % headroom. The 225.0 gr projectile in 0.338" calls for a 1:6.0 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. ReloadSwiss RS 70, Alliant Reloder-26, Accurate High Country rank at the top here: for .340 Weath. Mag. with the .338 | 225gr | Speer Grand Slam 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.