Load Specifications
Load data in caliber .300 WSM with .308 | 185gr | Lapua Mega bullet and 102 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-17 and ReloadSwiss RS 60.
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: 24"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2495 | <<locked>> | 84% | 56,478 psi | 89% | 2694 fps | 100% |
| Accurate 2700 | <<locked>> | 88% | 55,593 psi | 87% | 2723 fps | 98.7% |
| Accurate 3100ᴾ | <<locked>> | 100% | 51,097 psi | 80% | 2749 fps | 99.3% |
| Accurate 4064 | <<locked>> | 86% | 56,652 psi | 89% | 2746 fps | 100% |
| Accurate 4350 | <<locked>> | 94% | 57,464 psi | 90% | 2854 fps | 100% |
| ADI AR 2206H | <<locked>> | 82% | 55,854 psi | 88% | 2776 fps | 100% |
| ADI AR 2208 | <<locked>> | 88% | 56,898 psi | 89% | 2779 fps | 100% |
| ADI AR 2209 | <<locked>> | 98% | 54,665 psi | 86% | 2838 fps | 98% |
| ADI AR 2213ᴾ | <<locked>> | 100% | 52,402 psi | 82% | 2831 fps | 96.2% |
| Alliant Power Pro 2000-MR | <<locked>> | 84% | 56,275 psi | 88% | 2904 fps | 100% |
| Alliant Reloder- TS 15.5 | <<locked>> | 88% | 57,667 psi | 90% | 2802 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 84% | 54,346 psi | 85% | 2772 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 94% | 54,433 psi | 85% | 2854 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 90% | 55,564 psi | 87% | 2881 fps | 100% |
| Alliant Reloder-19ᴾ | <<locked>> | 100% | 57,377 psi | 90% | 2881 fps | 98.5% |
| Alliant Reloder-22ᴾ | <<locked>> | 100% | 50,981 psi | 80% | 2828 fps | 97.6% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 48,196 psi | 76% | 2769 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 42,090 psi | 66% | 2690 fps | 98.6% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 54,940 psi | 86% | 2956 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 82% | 55,637 psi | 87% | 2792 fps | 100% |
| Bofors RP15ᴾ | <<locked>> | 100% | 46,717 psi | 73% | 2753 fps | 96.5% |
| Bofors RP3 | <<locked>> | 86% | 54,824 psi | 86% | 2769 fps | 100% |
| Bofors RP5ᴾ | <<locked>> | 100% | 50,981 psi | 80% | 2828 fps | 97.6% |
| Bofors RP7 | <<locked>> | 90% | 54,491 psi | 85% | 2753 fps | 98.7% |
| Hodgdon H380 | <<locked>> | 86% | 55,463 psi | 87% | 2785 fps | 100% |
| Hodgdon H414 | <<locked>> | 90% | 57,435 psi | 90% | 2874 fps | 99.5% |
| Hodgdon H4350 | <<locked>> | 94% | 57,682 psi | 90% | 2838 fps | 98.7% |
| Hodgdon H4831 SCᴾ | <<locked>> | 100% | 55,027 psi | 86% | 2818 fps | 96.2% |
| Hodgdon H4895 | <<locked>> | 82% | 56,492 psi | 89% | 2785 fps | 100% |
| Hodgdon Hybrid 100V | <<locked>> | 96% | 54,694 psi | 86% | 2782 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 86% | 56,898 psi | 89% | 2825 fps | 100% |
| Hodgdon Superformance | <<locked>> | 92% | 56,101 psi | 88% | 2890 fps | 99.2% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,230 psi | 57% | 1706 fps | 100% |
| Hodgdon VARGET | <<locked>> | 86% | 56,565 psi | 89% | 2772 fps | 100% |
| IMR 3031 | <<locked>> | 84% | 55,709 psi | 87% | 2740 fps | 100% |
| IMR 4064 | <<locked>> | 88% | 55,970 psi | 88% | 2756 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 88% | 54,708 psi | 86% | 2733 fps | 99.1% |
| IMR 4350 | <<locked>> | 94% | 55,201 psi | 87% | 2785 fps | 98.9% |
| IMR 4451 Enduron | <<locked>> | 90% | 56,159 psi | 88% | 2782 fps | 99.2% |
| IMR 4831 | <<locked>> | 98% | 54,752 psi | 86% | 2805 fps | 100% |
| IMR 4895 | <<locked>> | 84% | 55,782 psi | 87% | 2799 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 98% | 54,273 psi | 85% | 2769 fps | 96.3% |
| IMR 7828 SSCᴾ | <<locked>> | 100% | 53,751 psi | 84% | 2867 fps | 96.7% |
| Lovex D073.6 | <<locked>> | 82% | 56,231 psi | 88% | 2749 fps | 100% |
| Lovex S060 | <<locked>> | 82% | 54,795 psi | 86% | 2700 fps | 100% |
| Lovex S062 | <<locked>> | 86% | 56,550 psi | 89% | 2756 fps | 100% |
| Lovex S065 | <<locked>> | 92% | 55,985 psi | 88% | 2776 fps | 99.8% |
| Lovex S070 | <<locked>> | 94% | 57,435 psi | 90% | 2818 fps | 99.5% |
| Lovex S071ᴾ | <<locked>> | 100% | 42,467 psi | 67% | 2602 fps | 98% |
| Norma 201 | <<locked>> | 82% | 54,665 psi | 86% | 2720 fps | 100% |
| Norma 202 | <<locked>> | 82% | 55,288 psi | 87% | 2717 fps | 100% |
| Norma 203B | <<locked>> | 86% | 57,232 psi | 90% | 2812 fps | 100% |
| Norma 204 | <<locked>> | 94% | 55,825 psi | 87% | 2835 fps | 98% |
| Norma MRPᴾ | <<locked>> | 100% | 54,027 psi | 85% | 2910 fps | 99.2% |
| Norma URP | <<locked>> | 94% | 56,057 psi | 88% | 2838 fps | 100% |
| Ramshot Big Game | <<locked>> | 84% | 54,418 psi | 85% | 2785 fps | 100% |
| Ramshot Grandᴾ | <<locked>> | 100% | 57,551 psi | 90% | 2936 fps | 97.8% |
| Ramshot Hunter | <<locked>> | 94% | 54,607 psi | 86% | 2838 fps | 99.6% |
| Ramshot Magnumᴾ | <<locked>> | 100% | 49,879 psi | 78% | 2789 fps | 97.9% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 36,999 psi | 58% | 1749 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 86% | 55,521 psi | 87% | 2772 fps | 99.5% |
| ReloadSwiss RS 52 | <<locked>> | 82% | 55,303 psi | 87% | 2838 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 88% | 55,201 psi | 87% | 2874 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 94% | 57,101 psi | 89% | 2877 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 94% | 55,680 psi | 87% | 2904 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 40,828 psi | 64% | 2697 fps | 96.4% |
| Rottweil R 902 | <<locked>> | 84% | 55,259 psi | 87% | 2720 fps | 100% |
| Rottweil R 903 | <<locked>> | 88% | 54,926 psi | 86% | 2762 fps | 100% |
| Rottweil R 904 | <<locked>> | 98% | 56,376 psi | 88% | 2808 fps | 97.2% |
| Rottweil R 905ᴾ | <<locked>> | 100% | 56,594 psi | 89% | 2867 fps | 98.5% |
| Rottweil R 907 | <<locked>> | 90% | 54,491 psi | 85% | 2753 fps | 98.7% |
| Shooters World Long Rifle | <<locked>> | 92% | 55,985 psi | 88% | 2776 fps | 99.8% |
| Shooters World Match Rifle | <<locked>> | 82% | 56,231 psi | 88% | 2749 fps | 100% |
| Shooters World Precision | <<locked>> | 86% | 56,550 psi | 89% | 2756 fps | 100% |
| Shooters World SW4350 | <<locked>> | 94% | 57,435 psi | 90% | 2818 fps | 99.5% |
| SNPE Vectan SP 11 | <<locked>> | 88% | 56,478 psi | 89% | 2822 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 82% | 57,217 psi | 90% | 2782 fps | 100% |
| SNPE Vectan SP 9 | <<locked>> | 82% | 54,259 psi | 85% | 2746 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 82% | 55,622 psi | 87% | 2651 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 88% | 56,231 psi | 88% | 2654 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 92% | 55,825 psi | 87% | 2730 fps | 99.2% |
| SNPE Vectan Tubal 8000ᴾ | <<locked>> | 100% | 56,086 psi | 88% | 2864 fps | 98.4% |
| Somchem S335 | <<locked>> | 82% | 55,216 psi | 87% | 2651 fps | 100% |
| Somchem S341 | <<locked>> | 82% | 56,666 psi | 89% | 2766 fps | 100% |
| Somchem S355 | <<locked>> | 88% | 55,100 psi | 86% | 2762 fps | 100% |
| Somchem S361 | <<locked>> | 96% | 54,752 psi | 86% | 2753 fps | 96.1% |
| Somchem S365 | <<locked>> | 96% | 55,100 psi | 86% | 2841 fps | 100% |
| Somchem S385ᴾ | <<locked>> | 100% | 57,421 psi | 90% | 2844 fps | 99.1% |
| Unknown powder | <<locked>> | 92% | 56,724 psi | 89% | 2844 fps | 100% |
| Vihtavuori N133 | <<locked>> | 84% | 55,579 psi | 87% | 2631 fps | 100% |
| Vihtavuori N135 | <<locked>> | 84% | 55,376 psi | 87% | 2677 fps | 100% |
| Vihtavuori N140 | <<locked>> | 84% | 54,955 psi | 86% | 2687 fps | 100% |
| Vihtavuori N150 | <<locked>> | 94% | 56,420 psi | 88% | 2740 fps | 100% |
| Vihtavuori N160 | <<locked>> | 92% | 57,232 psi | 90% | 2815 fps | 100% |
| Vihtavuori N165ᴾ | <<locked>> | 100% | 47,790 psi | 75% | 2684 fps | 97.3% |
| Vihtavuori N540 | <<locked>> | 84% | 54,781 psi | 86% | 2717 fps | 100% |
| Vihtavuori N550 | <<locked>> | 92% | 57,667 psi | 90% | 2861 fps | 100% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 53,809 psi | 84% | 2841 fps | 100% |
| Winchester 6.5 StaBALL | <<locked>> | 92% | 54,302 psi | 85% | 2753 fps | 100% |
| Winchester 760 | <<locked>> | 90% | 57,435 psi | 90% | 2874 fps | 99.5% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 43,439 psi | 68% | 2822 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 98% | 55,796 psi | 87% | 2812 fps | 98.1% |
Recommended = one of the top powders for this cartridge and bullet combination.
Start Load - Barrel Length: 24"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2495 | <<locked>> | 80% | 49,574 psi | 78% | 2602 fps | 100% |
| Accurate 2700 | <<locked>> | 80% | 42,801 psi | 67% | 2510 fps | 96.2% |
| Accurate 3100 | <<locked>> | 88% | 34,127 psi | 53% | 2428 fps | 95.5% |
| Accurate 4064 | <<locked>> | 80% | 46,963 psi | 74% | 2608 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 35,491 psi | 56% | 2470 fps | 97.7% |
| ADI AR 2206H | <<locked>> | 80% | 52,373 psi | 82% | 2723 fps | 100% |
| ADI AR 2208 | <<locked>> | 80% | 44,527 psi | 70% | 2582 fps | 99.7% |
| ADI AR 2209 | <<locked>> | 90% | 42,235 psi | 66% | 2618 fps | 95% |
| ADI AR 2213 | <<locked>> | 98% | 48,965 psi | 77% | 2769 fps | 95.4% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 48,892 psi | 77% | 2785 fps | 100% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 44,831 psi | 70% | 2605 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 80% | 47,935 psi | 75% | 2671 fps | 99.9% |
| Alliant Reloder-16 | <<locked>> | 80% | 34,925 psi | 55% | 2484 fps | 97.8% |
| Alliant Reloder-17 | 57.1 gr | 80% | 39,392 psi | 62% | 2605 fps | 99.8% |
| Alliant Reloder-19 | <<locked>> | 90% | 41,713 psi | 65% | 2608 fps | 95% |
| Alliant Reloder-22 | <<locked>> | 94% | 41,698 psi | 65% | 2654 fps | 95.2% |
| Alliant Reloder-23 | <<locked>> | 80% | 25,498 psi | 40% | 2241 fps | 95.1% |
| Alliant Reloder-25 | <<locked>> | 92% | 32,793 psi | 51% | 2464 fps | 95.3% |
| Alliant Reloder-26 | <<locked>> | 84% | 30,951 psi | 49% | 2461 fps | 95.4% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 52,228 psi | 82% | 2743 fps | 100% |
| Bofors RP15 | <<locked>> | 98% | 43,729 psi | 69% | 2694 fps | 95.7% |
| Bofors RP3 | <<locked>> | 80% | 45,078 psi | 71% | 2618 fps | 100% |
| Bofors RP5 | <<locked>> | 94% | 41,698 psi | 65% | 2654 fps | 95.2% |
| Bofors RP7 | <<locked>> | 80% | 39,885 psi | 63% | 2490 fps | 95.6% |
| Hodgdon H380 | <<locked>> | 80% | 45,527 psi | 71% | 2625 fps | 99.3% |
| Hodgdon H414 | <<locked>> | 80% | 40,843 psi | 64% | 2589 fps | 96.6% |
| Hodgdon H4350 | <<locked>> | 84% | 42,308 psi | 66% | 2575 fps | 95.6% |
| Hodgdon H4831 SC | <<locked>> | 98% | 51,372 psi | 81% | 2759 fps | 95.3% |
| Hodgdon H4895 | <<locked>> | 80% | 52,982 psi | 83% | 2733 fps | 100% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 32,518 psi | 51% | 2385 fps | 98.4% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 46,688 psi | 73% | 2671 fps | 100% |
| Hodgdon Superformance | <<locked>> | 82% | 39,262 psi | 62% | 2585 fps | 95.6% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,035 psi | 42% | 1522 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 47,123 psi | 74% | 2628 fps | 100% |
| IMR 3031 | <<locked>> | 80% | 49,284 psi | 77% | 2651 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 43,787 psi | 69% | 2559 fps | 99.7% |
| IMR 4166 Enduron | <<locked>> | 80% | 43,062 psi | 67% | 2530 fps | 97.1% |
| IMR 4350 | <<locked>> | 82% | 37,971 psi | 60% | 2470 fps | 95% |
| IMR 4451 Enduron | <<locked>> | 80% | 41,321 psi | 65% | 2523 fps | 96.5% |
| IMR 4831 | <<locked>> | 80% | 31,111 psi | 49% | 2352 fps | 96.3% |
| IMR 4895 | <<locked>> | 80% | 49,182 psi | 77% | 2700 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 96% | 51,126 psi | 80% | 2720 fps | 95.5% |
| IMR 7828 SSC | <<locked>> | 98% | 50,212 psi | 79% | 2805 fps | 95.8% |
| Lovex D073.6 | <<locked>> | 80% | 52,634 psi | 82% | 2700 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 51,445 psi | 81% | 2651 fps | 100% |
| Lovex S062 | <<locked>> | 80% | 46,963 psi | 74% | 2612 fps | 100% |
| Lovex S065 | <<locked>> | 80% | 38,754 psi | 61% | 2470 fps | 97.3% |
| Lovex S070 | <<locked>> | 80% | 36,970 psi | 58% | 2451 fps | 95.6% |
| Lovex S071 | <<locked>> | 92% | 32,967 psi | 52% | 2402 fps | 95% |
| Norma 201 | <<locked>> | 80% | 51,198 psi | 80% | 2671 fps | 100% |
| Norma 202 | <<locked>> | 80% | 51,808 psi | 81% | 2667 fps | 100% |
| Norma 203B | <<locked>> | 80% | 47,311 psi | 74% | 2657 fps | 100% |
| Norma 204 | <<locked>> | 86% | 42,685 psi | 67% | 2608 fps | 95.1% |
| Norma MRP | <<locked>> | 90% | 38,363 psi | 60% | 2612 fps | 95.6% |
| Norma URP | <<locked>> | 80% | 35,433 psi | 56% | 2467 fps | 97.6% |
| Ramshot Big Game | <<locked>> | 80% | 47,543 psi | 75% | 2680 fps | 100% |
| Ramshot Grand | <<locked>> | 94% | 46,021 psi | 72% | 2740 fps | 95% |
| Ramshot Hunter | <<locked>> | 80% | 34,418 psi | 54% | 2454 fps | 95.4% |
| Ramshot Magnum | <<locked>> | 94% | 39,958 psi | 63% | 2598 fps | 95.2% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,586 psi | 43% | 1562 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 45,585 psi | 71% | 2608 fps | 98.2% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 51,663 psi | 81% | 2785 fps | 100% |
| ReloadSwiss RS 60 | 57.1 gr | 80% | 41,858 psi | 66% | 2661 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 35,172 psi | 55% | 2487 fps | 97.3% |
| ReloadSwiss RS 70 | 58 gr | 80% | 34,476 psi | 54% | 2493 fps | 96.5% |
| ReloadSwiss RS 76 | <<locked>> | 98% | 38,043 psi | 60% | 2631 fps | 95.2% |
| Rottweil R 902 | <<locked>> | 80% | 48,979 psi | 77% | 2628 fps | 100% |
| Rottweil R 903 | <<locked>> | 80% | 42,409 psi | 66% | 2562 fps | 99.9% |
| Rottweil R 904 | <<locked>> | 92% | 46,673 psi | 73% | 2651 fps | 95.1% |
| Rottweil R 905 | <<locked>> | 92% | 43,482 psi | 68% | 2648 fps | 95.8% |
| Rottweil R 907 | <<locked>> | 80% | 39,885 psi | 63% | 2490 fps | 95.6% |
| Shooters World Long Rifle | <<locked>> | 80% | 38,754 psi | 61% | 2470 fps | 97.3% |
| Shooters World Match Rifle | <<locked>> | 80% | 52,634 psi | 82% | 2700 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 46,963 psi | 74% | 2612 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 36,970 psi | 58% | 2451 fps | 95.6% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 43,497 psi | 68% | 2615 fps | 99.8% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 53,374 psi | 84% | 2730 fps | 99.9% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 50,908 psi | 80% | 2697 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 52,257 psi | 82% | 2608 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 44,077 psi | 69% | 2480 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 37,913 psi | 59% | 2418 fps | 95.7% |
| SNPE Vectan Tubal 8000 | <<locked>> | 92% | 43,076 psi | 68% | 2641 fps | 95.7% |
| Somchem S335 | <<locked>> | 80% | 51,808 psi | 81% | 2605 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 53,127 psi | 83% | 2717 fps | 100% |
| Somchem S355 | <<locked>> | 80% | 42,786 psi | 67% | 2562 fps | 99.9% |
| Somchem S361 | <<locked>> | 94% | 51,082 psi | 80% | 2697 fps | 95.2% |
| Somchem S365 | <<locked>> | 80% | 31,908 psi | 50% | 2428 fps | 99.3% |
| Somchem S385 | <<locked>> | 88% | 38,754 psi | 61% | 2523 fps | 95.2% |
| Unknown powder | <<locked>> | 80% | 38,261 psi | 60% | 2520 fps | 97.7% |
| Vihtavuori N133 | <<locked>> | 80% | 49,356 psi | 77% | 2546 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 49,110 psi | 77% | 2592 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 48,675 psi | 76% | 2598 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 36,869 psi | 58% | 2421 fps | 99.9% |
| Vihtavuori N160 | <<locked>> | 80% | 38,464 psi | 60% | 2500 fps | 98.3% |
| Vihtavuori N165 | <<locked>> | 94% | 39,392 psi | 62% | 2526 fps | 95% |
| Vihtavuori N540 | <<locked>> | 80% | 48,196 psi | 76% | 2618 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 38,899 psi | 61% | 2539 fps | 98.3% |
| Vihtavuori N555 | <<locked>> | 80% | 27,862 psi | 44% | 2320 fps | 95.4% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 36,158 psi | 57% | 2444 fps | 99.4% |
| Winchester 760 | <<locked>> | 80% | 40,843 psi | 64% | 2589 fps | 96.6% |
| Winchester StaBALL HD | <<locked>> | 84% | 25,570 psi | 40% | 2323 fps | 95.8% |
| Winchester Supreme 780 | <<locked>> | 90% | 41,989 psi | 66% | 2582 fps | 95% |
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 111 powders for .300 WSM loaded with the .308 | 185gr | Lapua Mega. Alliant Reloder-26 delivers the highest muzzle velocity at 2,956 fps; across all powders the maximum-charge window runs from 1,706 fps to 2,956 fps. Accurate 3100 gives the best case fill at 100 %, and 111 of the 111 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (440 MPa), the top charges use 53–90 %, leaving at least 10 % headroom. The 185.0 gr projectile in 0.308" calls for a 1:15.5 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. ReloadSwiss RS 70, Alliant Reloder-17, ReloadSwiss RS 60 rank at the top here: for .300 WSM with the .308 | 185gr | Lapua Mega they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, Accurate MAGPRO, ADI AR 2225, Baschieri & Pellagri 109 burn incompletely and react more sensitively to barrel length and temperature. Always begin at the start load and work up in small increments while checking case and primer for pressure signs.