Load Specifications
Load data in caliber .300 WSM with .308 | 165gr | Swift Scirocco bullet and 99 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Alliant Power Pro 2000-MR, Hodgdon Superformance and Alliant Reloder-17.
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.
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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 2015 | <<locked>> | 84% | 56,550 psi | 89% | 2802 fps | 100% |
| Accurate 2495 | <<locked>> | 88% | 55,448 psi | 87% | 2828 fps | 100% |
| Accurate 2520 | <<locked>> | 84% | 55,506 psi | 87% | 2884 fps | 100% |
| Accurate 2700 | <<locked>> | 92% | 55,550 psi | 87% | 2835 fps | 97.2% |
| Accurate 3100ᴾ | <<locked>> | 100% | 42,322 psi | 66% | 2720 fps | 96.3% |
| Accurate 4064 | <<locked>> | 90% | 55,303 psi | 87% | 2874 fps | 100% |
| Accurate 4350 | <<locked>> | 98% | 55,143 psi | 86% | 2959 fps | 99.7% |
| ADI AR 2206H | <<locked>> | 86% | 55,550 psi | 87% | 2907 fps | 100% |
| ADI AR 2208 | <<locked>> | 92% | 56,492 psi | 89% | 2904 fps | 99.9% |
| ADI Benchmark 8208 | <<locked>> | 84% | 54,491 psi | 85% | 2854 fps | 100% |
| Alliant AR-Comp | <<locked>> | 84% | 55,637 psi | 87% | 2831 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 88% | 55,332 psi | 87% | 3028 fps | 99.9% |
| Alliant Reloder- TS 15.5 | <<locked>> | 92% | 56,695 psi | 89% | 2927 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 90% | 57,348 psi | 90% | 2953 fps | 100% |
| Alliant Reloder-16ᴾ | <<locked>> | 100% | 56,449 psi | 88% | 3022 fps | 99.9% |
| Alliant Reloder-17 | <<locked>> | 94% | 53,911 psi | 84% | 2999 fps | 100% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 40,364 psi | 63% | 2749 fps | 99.1% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 45,411 psi | 71% | 2920 fps | 98.5% |
| Baschieri & Pellagri 107 | <<locked>> | 86% | 55,347 psi | 87% | 2920 fps | 99.7% |
| Bofors RP3 | <<locked>> | 92% | 57,450 psi | 90% | 2943 fps | 100% |
| Bofors RP7 | <<locked>> | 96% | 57,392 psi | 90% | 2917 fps | 97.8% |
| Hodgdon Benchmark | <<locked>> | 84% | 56,159 psi | 88% | 2838 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 86% | 57,624 psi | 90% | 2936 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 82% | 55,956 psi | 88% | 2986 fps | 99.9% |
| Hodgdon H322 | <<locked>> | 82% | 54,491 psi | 85% | 2838 fps | 100% |
| Hodgdon H380 | <<locked>> | 90% | 54,926 psi | 86% | 2907 fps | 99.4% |
| Hodgdon H414 | <<locked>> | 94% | 56,188 psi | 88% | 2986 fps | 98.3% |
| Hodgdon H4350 | <<locked>> | 98% | 56,623 psi | 89% | 2943 fps | 97.1% |
| Hodgdon H4895 | <<locked>> | 86% | 56,130 psi | 88% | 2917 fps | 100% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 52,547 psi | 82% | 2887 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 90% | 55,927 psi | 88% | 2953 fps | 100% |
| Hodgdon Superformance | <<locked>> | 96% | 55,100 psi | 86% | 2995 fps | 97.7% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 35,578 psi | 56% | 1772 fps | 100% |
| Hodgdon VARGET | <<locked>> | 90% | 56,217 psi | 88% | 2904 fps | 100% |
| IMR 3031 | <<locked>> | 88% | 54,708 psi | 86% | 2877 fps | 100% |
| IMR 4064 | <<locked>> | 92% | 55,303 psi | 87% | 2877 fps | 99.9% |
| IMR 4166 Enduron | <<locked>> | 92% | 54,752 psi | 86% | 2851 fps | 97.9% |
| IMR 4350ᴾ | <<locked>> | 100% | 57,725 psi | 90% | 2940 fps | 97.9% |
| IMR 4451 Enduron | <<locked>> | 94% | 55,666 psi | 87% | 2894 fps | 97.9% |
| IMR 4831ᴾ | <<locked>> | 100% | 49,574 psi | 78% | 2854 fps | 99.2% |
| IMR 4895 | <<locked>> | 88% | 55,187 psi | 86% | 2930 fps | 100% |
| IMR 8208 XBR | <<locked>> | 84% | 54,491 psi | 85% | 2854 fps | 100% |
| Lovex D073.6 | <<locked>> | 86% | 55,506 psi | 87% | 2884 fps | 100% |
| Lovex S060 | <<locked>> | 86% | 55,013 psi | 86% | 2831 fps | 100% |
| Lovex S062 | <<locked>> | 90% | 55,912 psi | 88% | 2884 fps | 100% |
| Lovex S065 | <<locked>> | 96% | 55,201 psi | 87% | 2887 fps | 99% |
| Lovex S070 | <<locked>> | 98% | 56,275 psi | 88% | 2927 fps | 98.3% |
| Norma 201 | <<locked>> | 86% | 54,331 psi | 85% | 2851 fps | 100% |
| Norma 202 | <<locked>> | 86% | 54,839 psi | 86% | 2851 fps | 100% |
| Norma 203B | <<locked>> | 90% | 56,507 psi | 89% | 2936 fps | 100% |
| Norma 204 | <<locked>> | 98% | 54,853 psi | 86% | 2936 fps | 96.2% |
| Norma URPᴾ | <<locked>> | 100% | 57,711 psi | 90% | 2999 fps | 99.8% |
| Ramshot Big Game | <<locked>> | 90% | 57,290 psi | 90% | 2966 fps | 100% |
| Ramshot Hunterᴾ | <<locked>> | 100% | 56,565 psi | 89% | 2999 fps | 98.9% |
| Ramshot TAC | <<locked>> | 84% | 54,853 psi | 86% | 2877 fps | 99% |
| Ramshot Wild Boar | <<locked>> | 84% | 54,360 psi | 85% | 2894 fps | 100% |
| Ramshot X-Terminator | <<locked>> | 82% | 55,317 psi | 87% | 2858 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 36,042 psi | 56% | 1814 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 82% | 57,522 psi | 90% | 2887 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 90% | 54,955 psi | 86% | 2887 fps | 98.4% |
| ReloadSwiss RS 52 | <<locked>> | 86% | 54,215 psi | 85% | 2963 fps | 99.8% |
| ReloadSwiss RS 60 | <<locked>> | 94% | 57,479 psi | 90% | 3054 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 98% | 55,042 psi | 86% | 2986 fps | 99.6% |
| ReloadSwiss RS 70 | <<locked>> | 98% | 54,578 psi | 86% | 3012 fps | 99.4% |
| Rottweil R 901 | <<locked>> | 84% | 55,274 psi | 87% | 2831 fps | 100% |
| Rottweil R 902 | <<locked>> | 88% | 54,940 psi | 86% | 2851 fps | 100% |
| Rottweil R 903 | <<locked>> | 94% | 57,305 psi | 90% | 2936 fps | 100% |
| Rottweil R 907 | <<locked>> | 96% | 57,392 psi | 90% | 2917 fps | 97.8% |
| Shooters World Long Rifle | <<locked>> | 96% | 55,201 psi | 87% | 2887 fps | 99% |
| Shooters World Match Rifle | <<locked>> | 86% | 55,506 psi | 87% | 2884 fps | 100% |
| Shooters World Precision | <<locked>> | 90% | 55,912 psi | 88% | 2884 fps | 100% |
| Shooters World SW4350 | <<locked>> | 98% | 56,275 psi | 88% | 2927 fps | 98.3% |
| SNPE Vectan SP 11 | <<locked>> | 92% | 55,405 psi | 87% | 2946 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 86% | 57,130 psi | 90% | 2910 fps | 99.5% |
| SNPE Vectan SP 9 | <<locked>> | 88% | 57,682 psi | 90% | 2933 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 86% | 55,724 psi | 87% | 2789 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 92% | 56,188 psi | 88% | 2789 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 96% | 55,535 psi | 87% | 2841 fps | 98% |
| Somchem S321 | <<locked>> | 82% | 55,883 psi | 88% | 2890 fps | 100% |
| Somchem S335 | <<locked>> | 86% | 55,114 psi | 86% | 2785 fps | 100% |
| Somchem S341 | <<locked>> | 86% | 56,449 psi | 88% | 2897 fps | 100% |
| Somchem S355 | <<locked>> | 94% | 57,653 psi | 90% | 2933 fps | 100% |
| Somchem S365ᴾ | <<locked>> | 100% | 52,257 psi | 82% | 2949 fps | 100% |
| Somchem S385ᴾ | <<locked>> | 100% | 48,428 psi | 76% | 2825 fps | 96.1% |
| Unknown powder | <<locked>> | 96% | 55,390 psi | 87% | 2956 fps | 99.4% |
| Vihtavuori N130 | <<locked>> | 84% | 57,696 psi | 90% | 2782 fps | 100% |
| Vihtavuori N133 | <<locked>> | 88% | 55,448 psi | 87% | 2766 fps | 100% |
| Vihtavuori N135 | <<locked>> | 88% | 54,607 psi | 86% | 2812 fps | 100% |
| Vihtavuori N140 | <<locked>> | 88% | 54,621 psi | 86% | 2822 fps | 100% |
| Vihtavuori N150 | <<locked>> | 98% | 55,405 psi | 87% | 2864 fps | 100% |
| Vihtavuori N160 | <<locked>> | 96% | 55,811 psi | 87% | 2927 fps | 99.7% |
| Vihtavuori N530 | <<locked>> | 84% | 57,682 psi | 90% | 2910 fps | 100% |
| Vihtavuori N540 | <<locked>> | 88% | 54,259 psi | 85% | 2848 fps | 100% |
| Vihtavuori N550 | <<locked>> | 96% | 56,086 psi | 88% | 2976 fps | 99.7% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 44,541 psi | 70% | 2831 fps | 99% |
| Winchester 6.5 StaBALL | <<locked>> | 98% | 57,246 psi | 90% | 2923 fps | 100% |
| Winchester 748 | <<locked>> | 82% | 55,724 psi | 87% | 2913 fps | 100% |
| Winchester 760 | <<locked>> | 94% | 56,188 psi | 88% | 2986 fps | 98.3% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 36,143 psi | 57% | 2753 fps | 99% |
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 2015 | <<locked>> | 80% | 49,908 psi | 78% | 2710 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 42,627 psi | 67% | 2635 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 48,414 psi | 76% | 2776 fps | 100% |
| Accurate 2700 | <<locked>> | 86% | 45,542 psi | 71% | 2667 fps | 95% |
| Accurate 3100 | <<locked>> | 98% | 39,465 psi | 62% | 2661 fps | 95.4% |
| Accurate 4064 | <<locked>> | 80% | 40,306 psi | 63% | 2631 fps | 100% |
| Accurate 4350 | <<locked>> | 84% | 33,997 psi | 53% | 2559 fps | 95.5% |
| ADI AR 2206H | <<locked>> | 80% | 46,137 psi | 72% | 2749 fps | 99.4% |
| ADI AR 2208 | <<locked>> | 80% | 39,059 psi | 61% | 2592 fps | 97.6% |
| ADI Benchmark 8208 | <<locked>> | 80% | 48,225 psi | 76% | 2756 fps | 100% |
| Alliant AR-Comp | <<locked>> | 80% | 48,762 psi | 76% | 2736 fps | 100% |
| Alliant Power Pro 2000-MR | 54.9 gr | 80% | 41,930 psi | 66% | 2779 fps | 98.3% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 38,899 psi | 61% | 2618 fps | 98.9% |
| Alliant Reloder-15 | <<locked>> | 80% | 41,829 psi | 66% | 2684 fps | 98.4% |
| Alliant Reloder-16 | <<locked>> | 84% | 34,200 psi | 54% | 2572 fps | 95.6% |
| Alliant Reloder-17 | 54.1 gr | 80% | 33,649 psi | 53% | 2589 fps | 97.3% |
| Alliant Reloder-23 | <<locked>> | 90% | 29,617 psi | 46% | 2474 fps | 95.2% |
| Alliant Reloder-26 | <<locked>> | 94% | 36,651 psi | 57% | 2720 fps | 95.8% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 45,397 psi | 71% | 2753 fps | 98.6% |
| Bofors RP3 | <<locked>> | 80% | 38,624 psi | 61% | 2621 fps | 98.9% |
| Bofors RP7 | <<locked>> | 88% | 44,860 psi | 70% | 2703 fps | 95.1% |
| Hodgdon Benchmark | <<locked>> | 80% | 49,850 psi | 78% | 2740 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 80% | 47,094 psi | 74% | 2776 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 80% | 52,141 psi | 82% | 2927 fps | 99.7% |
| Hodgdon H322 | <<locked>> | 80% | 51,024 psi | 80% | 2785 fps | 100% |
| Hodgdon H380 | <<locked>> | 80% | 39,450 psi | 62% | 2625 fps | 96.7% |
| Hodgdon H414 | <<locked>> | 86% | 42,612 psi | 67% | 2743 fps | 95.3% |
| Hodgdon H4350 | <<locked>> | 94% | 50,082 psi | 78% | 2835 fps | 95.7% |
| Hodgdon H4895 | <<locked>> | 80% | 46,615 psi | 73% | 2759 fps | 99.7% |
| Hodgdon Hybrid 100V | <<locked>> | 82% | 29,486 psi | 46% | 2415 fps | 95.5% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 40,132 psi | 63% | 2680 fps | 99.2% |
| Hodgdon Superformance | 64.3 gr | 90% | 44,411 psi | 70% | 2802 fps | 95.1% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,585 psi | 42% | 1585 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 41,379 psi | 65% | 2648 fps | 99% |
| IMR 3031 | <<locked>> | 80% | 42,482 psi | 67% | 2684 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 38,421 psi | 60% | 2572 fps | 97.7% |
| IMR 4166 Enduron | <<locked>> | 84% | 43,018 psi | 67% | 2638 fps | 95.2% |
| IMR 4350 | <<locked>> | 92% | 45,078 psi | 71% | 2730 fps | 95.2% |
| IMR 4451 Enduron | <<locked>> | 86% | 43,816 psi | 69% | 2684 fps | 95.3% |
| IMR 4831 | <<locked>> | 88% | 33,924 psi | 53% | 2539 fps | 95.5% |
| IMR 4895 | <<locked>> | 80% | 42,873 psi | 67% | 2713 fps | 99% |
| IMR 8208 XBR | <<locked>> | 80% | 48,225 psi | 76% | 2756 fps | 100% |
| Lovex D073.6 | <<locked>> | 80% | 45,339 psi | 71% | 2726 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 45,788 psi | 72% | 2680 fps | 99.4% |
| Lovex S062 | <<locked>> | 80% | 40,973 psi | 64% | 2631 fps | 99.5% |
| Lovex S065 | <<locked>> | 84% | 38,348 psi | 60% | 2575 fps | 95.4% |
| Lovex S070 | <<locked>> | 88% | 41,191 psi | 65% | 2657 fps | 95% |
| Norma 201 | <<locked>> | 80% | 45,034 psi | 71% | 2697 fps | 99.8% |
| Norma 202 | <<locked>> | 80% | 45,426 psi | 71% | 2703 fps | 100% |
| Norma 203B | <<locked>> | 80% | 41,220 psi | 65% | 2674 fps | 98.7% |
| Norma 204 | <<locked>> | 96% | 51,329 psi | 80% | 2881 fps | 95.3% |
| Norma URP | <<locked>> | 84% | 34,287 psi | 54% | 2559 fps | 95.4% |
| Ramshot Big Game | <<locked>> | 80% | 40,698 psi | 64% | 2684 fps | 98.5% |
| Ramshot Hunter | <<locked>> | 90% | 40,828 psi | 64% | 2713 fps | 95.7% |
| Ramshot TAC | <<locked>> | 80% | 48,095 psi | 75% | 2762 fps | 98% |
| Ramshot Wild Boar | <<locked>> | 80% | 47,703 psi | 75% | 2782 fps | 99.5% |
| Ramshot X-Terminator | <<locked>> | 80% | 51,779 psi | 81% | 2802 fps | 99.8% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 26,890 psi | 42% | 1621 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 80% | 53,969 psi | 85% | 2835 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 39,711 psi | 62% | 2605 fps | 95% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 44,019 psi | 69% | 2785 fps | 98.8% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 35,810 psi | 56% | 2654 fps | 99.7% |
| ReloadSwiss RS 62 | <<locked>> | 86% | 36,289 psi | 57% | 2635 fps | 95.9% |
| ReloadSwiss RS 70 | <<locked>> | 88% | 38,725 psi | 61% | 2700 fps | 96% |
| Rottweil R 901 | <<locked>> | 80% | 49,168 psi | 77% | 2740 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 42,931 psi | 67% | 2651 fps | 99.6% |
| Rottweil R 903 | <<locked>> | 80% | 36,347 psi | 57% | 2566 fps | 98.2% |
| Rottweil R 907 | <<locked>> | 88% | 44,860 psi | 70% | 2703 fps | 95.1% |
| Shooters World Long Rifle | <<locked>> | 84% | 38,348 psi | 60% | 2575 fps | 95.4% |
| Shooters World Match Rifle | <<locked>> | 80% | 45,339 psi | 71% | 2726 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 40,973 psi | 64% | 2631 fps | 99.5% |
| Shooters World SW4350 | <<locked>> | 88% | 41,191 psi | 65% | 2657 fps | 95% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 37,231 psi | 58% | 2612 fps | 97.7% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 46,427 psi | 73% | 2736 fps | 98.2% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 44,440 psi | 70% | 2713 fps | 99.2% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 46,209 psi | 72% | 2644 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 38,566 psi | 60% | 2510 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 88% | 42,757 psi | 67% | 2625 fps | 95.2% |
| Somchem S321 | <<locked>> | 80% | 52,214 psi | 82% | 2835 fps | 100% |
| Somchem S335 | <<locked>> | 80% | 45,934 psi | 72% | 2648 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 46,224 psi | 72% | 2733 fps | 99.4% |
| Somchem S355 | <<locked>> | 80% | 37,072 psi | 58% | 2569 fps | 98.2% |
| Somchem S365 | <<locked>> | 80% | 27,050 psi | 42% | 2398 fps | 95.9% |
| Somchem S385 | <<locked>> | 98% | 45,382 psi | 71% | 2769 fps | 95.3% |
| Unknown powder | <<locked>> | 84% | 37,275 psi | 58% | 2618 fps | 95.7% |
| Vihtavuori N130 | <<locked>> | 80% | 51,271 psi | 80% | 2694 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 43,787 psi | 69% | 2595 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 42,409 psi | 66% | 2628 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 42,395 psi | 66% | 2628 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 31,662 psi | 50% | 2421 fps | 98% |
| Vihtavuori N160 | <<locked>> | 82% | 34,925 psi | 55% | 2539 fps | 95.6% |
| Vihtavuori N530 | <<locked>> | 80% | 50,647 psi | 79% | 2805 fps | 100% |
| Vihtavuori N540 | <<locked>> | 80% | 42,090 psi | 66% | 2651 fps | 100% |
| Vihtavuori N550 | <<locked>> | 82% | 35,491 psi | 56% | 2582 fps | 95.7% |
| Vihtavuori N555 | <<locked>> | 90% | 32,024 psi | 50% | 2556 fps | 95.5% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 31,314 psi | 49% | 2431 fps | 96.5% |
| Winchester 748 | <<locked>> | 80% | 51,967 psi | 81% | 2858 fps | 100% |
| Winchester 760 | <<locked>> | 86% | 42,612 psi | 67% | 2743 fps | 95.3% |
| Winchester StaBALL HD | <<locked>> | 94% | 29,776 psi | 47% | 2552 fps | 95.9% |
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 118 powders for .300 WSM loaded with the .308 | 165gr | Swift Scirocco. ReloadSwiss RS 60 delivers the highest muzzle velocity at 3,054 fps; across all powders the maximum-charge window runs from 1,772 fps to 3,054 fps. Accurate 3100 gives the best case fill at 100 %, and 118 of the 118 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 165.0 gr projectile in 0.308" calls for a 1:11.5 twist; slower twists will usually not stabilise this weight. Accurate 3100, ADI AR 2209, Alliant Reloder-16 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 Power Pro 2000-MR, Hodgdon Superformance, Alliant Reloder-17 rank at the top here: for .300 WSM with the .308 | 165gr | Swift Scirocco they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, Alliant Reloder-22, Alliant Reloder-25, Bofors RP15 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.