Load Specifications
Load data in caliber .300 Weath. Mag. with .308 | 165gr | Swift Scirocco bullet and 88 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Alliant Reloder-26, Norma MRP 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.
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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 2495 | <<locked>> | 82% | 57,058 psi | 89% | 2900 fps | 100% |
| Accurate 2700 | <<locked>> | 82% | 54,462 psi | 85% | 2920 fps | 98.5% |
| Accurate 3100ᴾ | <<locked>> | 100% | 56,666 psi | 89% | 3018 fps | 99.7% |
| Accurate 4064 | <<locked>> | 84% | 57,319 psi | 90% | 2956 fps | 100% |
| Accurate 4350 | <<locked>> | 90% | 54,824 psi | 86% | 3015 fps | 100% |
| ADI AR 2208 | <<locked>> | 86% | 57,246 psi | 90% | 2989 fps | 100% |
| ADI AR 2209 | <<locked>> | 96% | 55,767 psi | 87% | 3058 fps | 98.1% |
| ADI AR 2213ᴾ | <<locked>> | 100% | 57,261 psi | 90% | 3117 fps | 97.3% |
| Alliant Power Pro 2000-MR | <<locked>> | 82% | 56,956 psi | 89% | 3120 fps | 100% |
| Alliant Reloder- TS 15.5 | <<locked>> | 84% | 54,665 psi | 86% | 2959 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 82% | 54,824 psi | 86% | 2982 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 92% | 55,564 psi | 87% | 3074 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 88% | 56,840 psi | 89% | 3097 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 96% | 55,143 psi | 86% | 3048 fps | 98.1% |
| Alliant Reloder-22ᴾ | <<locked>> | 100% | 56,405 psi | 88% | 3107 fps | 98.4% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 53,359 psi | 84% | 3038 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 46,296 psi | 73% | 2959 fps | 99.3% |
| Alliant Reloder-26 | <<locked>> | 98% | 57,624 psi | 90% | 3186 fps | 100% |
| Bofors RP15ᴾ | <<locked>> | 100% | 51,503 psi | 81% | 3022 fps | 97.4% |
| Bofors RP3 | <<locked>> | 84% | 55,521 psi | 87% | 2979 fps | 100% |
| Bofors RP5ᴾ | <<locked>> | 100% | 56,405 psi | 88% | 3107 fps | 98.4% |
| Bofors RP7 | <<locked>> | 88% | 54,897 psi | 86% | 2963 fps | 98.7% |
| Hodgdon H380 | <<locked>> | 84% | 55,970 psi | 88% | 2999 fps | 100% |
| Hodgdon H414 | <<locked>> | 90% | 56,956 psi | 89% | 3071 fps | 99.4% |
| Hodgdon H4350 | <<locked>> | 88% | 56,536 psi | 89% | 3028 fps | 98.5% |
| Hodgdon H4831 | <<locked>> | 98% | 57,435 psi | 90% | 3058 fps | 96.7% |
| Hodgdon H4831 SC | <<locked>> | 98% | 56,014 psi | 88% | 3031 fps | 96.4% |
| Hodgdon Hybrid 100V | <<locked>> | 94% | 55,753 psi | 87% | 2992 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 82% | 57,130 psi | 90% | 3028 fps | 100% |
| Hodgdon Retumboᴾ | <<locked>> | 100% | 45,194 psi | 71% | 2989 fps | 96.7% |
| Hodgdon Superformance | <<locked>> | 90% | 57,406 psi | 90% | 3107 fps | 99.3% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,492 psi | 57% | 1880 fps | 100% |
| Hodgdon VARGET | <<locked>> | 82% | 57,624 psi | 90% | 2992 fps | 100% |
| IMR 4064 | <<locked>> | 84% | 56,594 psi | 89% | 2969 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 82% | 55,767 psi | 87% | 2956 fps | 99.2% |
| IMR 4350 | <<locked>> | 92% | 55,956 psi | 88% | 2995 fps | 98.9% |
| IMR 4451 Enduron | <<locked>> | 88% | 56,550 psi | 89% | 2992 fps | 99.2% |
| IMR 4831 | <<locked>> | 92% | 55,216 psi | 87% | 3005 fps | 100% |
| IMR 4895 | <<locked>> | 82% | 56,231 psi | 88% | 3012 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 96% | 55,158 psi | 86% | 2982 fps | 96.4% |
| IMR 7828 SSCᴾ | <<locked>> | 100% | 54,447 psi | 85% | 3081 fps | 96.8% |
| Lovex S062 | <<locked>> | 84% | 56,985 psi | 89% | 2966 fps | 100% |
| Lovex S065 | <<locked>> | 90% | 56,608 psi | 89% | 2986 fps | 99.8% |
| Lovex S070 | <<locked>> | 90% | 54,592 psi | 86% | 2976 fps | 99.2% |
| Lovex S071ᴾ | <<locked>> | 100% | 46,963 psi | 74% | 2861 fps | 98.7% |
| Norma 203B | <<locked>> | 84% | 57,667 psi | 90% | 3022 fps | 100% |
| Norma 204 | <<locked>> | 92% | 56,927 psi | 89% | 3051 fps | 98.2% |
| Norma MRP | <<locked>> | 98% | 55,999 psi | 88% | 3136 fps | 99.3% |
| Norma URP | <<locked>> | 92% | 57,072 psi | 89% | 3054 fps | 100% |
| Ramshot Big Game | <<locked>> | 82% | 54,955 psi | 86% | 2995 fps | 100% |
| Ramshot Grandᴾ | <<locked>> | 100% | 55,201 psi | 87% | 3104 fps | 97.4% |
| Ramshot Hunter | <<locked>> | 92% | 55,898 psi | 88% | 3054 fps | 99.7% |
| Ramshot Magnumᴾ | <<locked>> | 100% | 49,269 psi | 77% | 2966 fps | 97.8% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 37,144 psi | 58% | 1923 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 84% | 55,709 psi | 87% | 2979 fps | 99.5% |
| ReloadSwiss RS 60 | <<locked>> | 86% | 56,420 psi | 88% | 3091 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 90% | 54,650 psi | 86% | 3035 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 92% | 56,971 psi | 89% | 3127 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 45,368 psi | 71% | 2986 fps | 97.9% |
| Rottweil R 902 | <<locked>> | 82% | 55,521 psi | 87% | 2927 fps | 100% |
| Rottweil R 903 | <<locked>> | 86% | 55,796 psi | 87% | 2976 fps | 100% |
| Rottweil R 904 | <<locked>> | 96% | 57,377 psi | 90% | 3028 fps | 97.4% |
| Rottweil R 905 | <<locked>> | 96% | 54,360 psi | 85% | 3031 fps | 98.1% |
| Rottweil R 907 | <<locked>> | 88% | 54,897 psi | 86% | 2963 fps | 98.7% |
| Shooters World Long Rifle | <<locked>> | 90% | 56,608 psi | 89% | 2986 fps | 99.8% |
| Shooters World Precision | <<locked>> | 84% | 56,985 psi | 89% | 2966 fps | 100% |
| Shooters World SW4350 | <<locked>> | 90% | 54,592 psi | 86% | 2976 fps | 99.2% |
| SNPE Vectan SP 11 | <<locked>> | 86% | 57,217 psi | 90% | 3035 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 86% | 56,463 psi | 88% | 2854 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 90% | 56,420 psi | 88% | 2940 fps | 99.3% |
| SNPE Vectan Tubal 8000 | <<locked>> | 98% | 57,653 psi | 90% | 3087 fps | 98.6% |
| Somchem S355 | <<locked>> | 86% | 55,550 psi | 87% | 2969 fps | 100% |
| Somchem S361 | <<locked>> | 94% | 55,579 psi | 87% | 2963 fps | 96.3% |
| Somchem S365 | <<locked>> | 94% | 56,710 psi | 89% | 3058 fps | 100% |
| Somchem S385 | <<locked>> | 96% | 55,013 psi | 86% | 3005 fps | 98.8% |
| Vihtavuori N135 | <<locked>> | 82% | 55,956 psi | 88% | 2884 fps | 100% |
| Vihtavuori N140 | <<locked>> | 82% | 56,014 psi | 88% | 2897 fps | 100% |
| Vihtavuori N150 | <<locked>> | 88% | 56,826 psi | 89% | 2943 fps | 100% |
| Vihtavuori N160 | <<locked>> | 90% | 55,535 psi | 87% | 2992 fps | 100% |
| Vihtavuori N165ᴾ | <<locked>> | 100% | 54,447 psi | 85% | 2982 fps | 98.4% |
| Vihtavuori N540 | <<locked>> | 82% | 54,157 psi | 85% | 2894 fps | 100% |
| Vihtavuori N550 | <<locked>> | 90% | 54,781 psi | 86% | 2999 fps | 100% |
| Vihtavuori N555 | <<locked>> | 98% | 55,869 psi | 88% | 3064 fps | 100% |
| Vihtavuori N560 | <<locked>> | 98% | 56,202 psi | 88% | 3123 fps | 96.8% |
| Winchester 6.5 StaBALL | <<locked>> | 90% | 55,216 psi | 87% | 2959 fps | 100% |
| Winchester 760 | <<locked>> | 90% | 57,174 psi | 90% | 3074 fps | 99.4% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 48,747 psi | 76% | 3100 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 98% | 55,245 psi | 87% | 2999 fps | 98% |
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% | 53,403 psi | 84% | 2848 fps | 100% |
| Accurate 2700 | <<locked>> | 80% | 50,908 psi | 80% | 2858 fps | 98% |
| Accurate 3100 | <<locked>> | 86% | 35,099 psi | 55% | 2612 fps | 95.5% |
| Accurate 4064 | <<locked>> | 80% | 50,618 psi | 79% | 2854 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 38,870 psi | 61% | 2717 fps | 98.3% |
| ADI AR 2208 | <<locked>> | 80% | 47,485 psi | 74% | 2828 fps | 99.8% |
| ADI AR 2209 | <<locked>> | 88% | 42,815 psi | 67% | 2812 fps | 95% |
| ADI AR 2213 | <<locked>> | 96% | 49,879 psi | 78% | 2982 fps | 95.5% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 53,026 psi | 83% | 3058 fps | 100% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 48,283 psi | 76% | 2858 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 80% | 51,416 psi | 81% | 2927 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 80% | 37,608 psi | 59% | 2723 fps | 98.3% |
| Alliant Reloder-17 | <<locked>> | 80% | 42,815 psi | 67% | 2854 fps | 99.9% |
| Alliant Reloder-19 | <<locked>> | 88% | 42,525 psi | 67% | 2805 fps | 95% |
| Alliant Reloder-22 | <<locked>> | 92% | 42,975 psi | 67% | 2858 fps | 95.3% |
| Alliant Reloder-23 | <<locked>> | 80% | 27,688 psi | 43% | 2467 fps | 96% |
| Alliant Reloder-25 | <<locked>> | 90% | 33,489 psi | 52% | 2651 fps | 95.3% |
| Alliant Reloder-26 | 70.4 gr | 82% | 31,821 psi | 50% | 2644 fps | 95.4% |
| Bofors RP15 | <<locked>> | 94% | 42,380 psi | 66% | 2844 fps | 95% |
| Bofors RP3 | <<locked>> | 80% | 48,660 psi | 76% | 2867 fps | 100% |
| Bofors RP5 | <<locked>> | 92% | 42,975 psi | 67% | 2858 fps | 95.3% |
| Bofors RP7 | <<locked>> | 80% | 42,641 psi | 67% | 2733 fps | 96.2% |
| Hodgdon H380 | <<locked>> | 80% | 48,979 psi | 77% | 2881 fps | 99.6% |
| Hodgdon H414 | <<locked>> | 80% | 40,799 psi | 64% | 2766 fps | 96.3% |
| Hodgdon H4350 | <<locked>> | 80% | 43,598 psi | 68% | 2789 fps | 95.7% |
| Hodgdon H4831 | <<locked>> | 96% | 53,490 psi | 84% | 2989 fps | 95.8% |
| Hodgdon H4831 SC | <<locked>> | 96% | 52,388 psi | 82% | 2972 fps | 95.5% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 35,201 psi | 55% | 2615 fps | 98.9% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 53,577 psi | 84% | 2976 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 98% | 42,337 psi | 66% | 2920 fps | 95.6% |
| Hodgdon Superformance | <<locked>> | 80% | 39,784 psi | 62% | 2776 fps | 95.6% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,238 psi | 43% | 1680 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 54,027 psi | 85% | 2940 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 49,922 psi | 78% | 2864 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 80% | 52,156 psi | 82% | 2897 fps | 98.7% |
| IMR 4350 | <<locked>> | 82% | 40,901 psi | 64% | 2713 fps | 95.7% |
| IMR 4451 Enduron | <<locked>> | 80% | 43,976 psi | 69% | 2762 fps | 97.1% |
| IMR 4831 | <<locked>> | 80% | 37,289 psi | 58% | 2667 fps | 98% |
| IMR 4895 | <<locked>> | 80% | 52,736 psi | 83% | 2956 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 94% | 51,793 psi | 81% | 2927 fps | 95.6% |
| IMR 7828 SSC | <<locked>> | 96% | 47,616 psi | 75% | 2953 fps | 95% |
| Lovex S062 | <<locked>> | 80% | 50,357 psi | 79% | 2864 fps | 100% |
| Lovex S065 | <<locked>> | 80% | 41,582 psi | 65% | 2713 fps | 97.8% |
| Lovex S070 | <<locked>> | 80% | 39,842 psi | 62% | 2690 fps | 96.2% |
| Lovex S071 | <<locked>> | 90% | 34,069 psi | 53% | 2585 fps | 95.1% |
| Norma 203B | <<locked>> | 80% | 50,749 psi | 80% | 2913 fps | 100% |
| Norma 204 | <<locked>> | 84% | 43,352 psi | 68% | 2802 fps | 95% |
| Norma MRP | 73.4 gr | 88% | 39,465 psi | 62% | 2812 fps | 95.7% |
| Norma URP | <<locked>> | 80% | 38,508 psi | 60% | 2710 fps | 98.1% |
| Ramshot Big Game | <<locked>> | 80% | 51,358 psi | 80% | 2936 fps | 100% |
| Ramshot Grand | <<locked>> | 96% | 47,761 psi | 75% | 2966 fps | 95.5% |
| Ramshot Hunter | <<locked>> | 80% | 37,391 psi | 59% | 2694 fps | 96.1% |
| Ramshot Magnum | <<locked>> | 96% | 42,409 psi | 66% | 2831 fps | 95.9% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,891 psi | 44% | 1722 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 48,950 psi | 77% | 2861 fps | 98.7% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 45,484 psi | 71% | 2910 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 38,696 psi | 61% | 2733 fps | 98% |
| ReloadSwiss RS 70 | 68.1 gr | 80% | 37,405 psi | 59% | 2740 fps | 97.3% |
| ReloadSwiss RS 76 | <<locked>> | 96% | 39,291 psi | 62% | 2838 fps | 95.6% |
| Rottweil R 902 | <<locked>> | 80% | 52,069 psi | 82% | 2874 fps | 100% |
| Rottweil R 903 | <<locked>> | 80% | 45,788 psi | 72% | 2812 fps | 100% |
| Rottweil R 904 | <<locked>> | 90% | 47,398 psi | 74% | 2854 fps | 95.1% |
| Rottweil R 905 | <<locked>> | 88% | 41,727 psi | 65% | 2789 fps | 95% |
| Rottweil R 907 | <<locked>> | 80% | 42,641 psi | 67% | 2733 fps | 96.2% |
| Shooters World Long Rifle | <<locked>> | 80% | 41,582 psi | 65% | 2713 fps | 97.8% |
| Shooters World Precision | <<locked>> | 80% | 50,357 psi | 79% | 2864 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 39,842 psi | 62% | 2690 fps | 96.2% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 47,007 psi | 74% | 2867 fps | 99.9% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 46,804 psi | 73% | 2713 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 40,814 psi | 64% | 2654 fps | 96.4% |
| SNPE Vectan Tubal 8000 | <<locked>> | 90% | 44,208 psi | 69% | 2844 fps | 95.8% |
| Somchem S355 | <<locked>> | 80% | 46,021 psi | 72% | 2808 fps | 100% |
| Somchem S361 | <<locked>> | 92% | 52,011 psi | 82% | 2904 fps | 95.4% |
| Somchem S365 | <<locked>> | 80% | 35,070 psi | 55% | 2667 fps | 99.7% |
| Somchem S385 | <<locked>> | 86% | 39,755 psi | 62% | 2717 fps | 95.3% |
| Vihtavuori N135 | <<locked>> | 80% | 52,402 psi | 82% | 2835 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 52,533 psi | 82% | 2848 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 43,976 psi | 69% | 2736 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 39,943 psi | 63% | 2710 fps | 98.4% |
| Vihtavuori N165 | <<locked>> | 92% | 41,698 psi | 65% | 2749 fps | 95.5% |
| Vihtavuori N540 | <<locked>> | 80% | 50,879 psi | 80% | 2844 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 39,407 psi | 62% | 2710 fps | 98.1% |
| Vihtavuori N555 | <<locked>> | 80% | 30,719 psi | 48% | 2549 fps | 96.2% |
| Vihtavuori N560 | <<locked>> | 94% | 49,008 psi | 77% | 2992 fps | 95% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 39,088 psi | 61% | 2677 fps | 99.7% |
| Winchester 760 | <<locked>> | 80% | 40,799 psi | 64% | 2766 fps | 96.3% |
| Winchester StaBALL HD | <<locked>> | 82% | 26,136 psi | 41% | 2493 fps | 95.7% |
| Winchester Supreme 780 | <<locked>> | 92% | 44,788 psi | 70% | 2815 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 88 powders for .300 Weath. Mag. loaded with the .308 | 165gr | Swift Scirocco. Alliant Reloder-26 delivers the highest muzzle velocity at 3,186 fps; across all powders the maximum-charge window runs from 1,880 fps to 3,186 fps. Accurate 3100 gives the best case fill at 100 %, and 88 of the 88 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 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 2213, Alliant Reloder-22 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, Norma MRP, ReloadSwiss RS 70 rank at the top here: for .300 Weath. Mag. with the .308 | 165gr | Swift Scirocco 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.