Load Specifications
Load data in caliber .300 Win. Mag. with .307 | 165gr | Rhino Penetrator bullet and 96 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% | 54,955 psi | 88% | 2841 fps | 100% |
| Accurate 2700 | <<locked>> | 88% | 54,404 psi | 87% | 2858 fps | 97.9% |
| Accurate 3100ᴾ | <<locked>> | 100% | 49,632 psi | 80% | 2874 fps | 98.6% |
| Accurate 4064 | <<locked>> | 86% | 55,216 psi | 89% | 2894 fps | 100% |
| Accurate 4350 | <<locked>> | 94% | 55,724 psi | 89% | 2995 fps | 99.9% |
| ADI AR 2206H | <<locked>> | 82% | 54,549 psi | 87% | 2920 fps | 100% |
| ADI AR 2208 | <<locked>> | 88% | 55,782 psi | 89% | 2927 fps | 100% |
| ADI AR 2209 | <<locked>> | 98% | 53,301 psi | 85% | 2972 fps | 96.9% |
| Alliant Power Pro 2000-MR | <<locked>> | 84% | 54,766 psi | 88% | 3051 fps | 100% |
| Alliant Reloder- TS 15.5 | <<locked>> | 88% | 56,318 psi | 90% | 2949 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 84% | 53,055 psi | 85% | 2917 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 94% | 53,069 psi | 85% | 2999 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 90% | 54,056 psi | 87% | 3025 fps | 100% |
| Alliant Reloder-19ᴾ | <<locked>> | 100% | 55,941 psi | 90% | 3018 fps | 97.6% |
| Alliant Reloder-22ᴾ | <<locked>> | 100% | 49,472 psi | 79% | 2953 fps | 96.4% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 46,746 psi | 75% | 2900 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 40,828 psi | 65% | 2802 fps | 97.4% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 53,359 psi | 86% | 3091 fps | 99.9% |
| Baschieri & Pellagri 107 | <<locked>> | 82% | 54,447 psi | 87% | 2940 fps | 99.9% |
| Bofors RP3 | <<locked>> | 86% | 53,650 psi | 86% | 2913 fps | 100% |
| Bofors RP5ᴾ | <<locked>> | 100% | 49,472 psi | 79% | 2953 fps | 96.4% |
| Bofors RP7 | <<locked>> | 90% | 53,330 psi | 86% | 2890 fps | 97.9% |
| Hodgdon H380 | <<locked>> | 86% | 53,998 psi | 87% | 2927 fps | 99.7% |
| Hodgdon H414 | <<locked>> | 90% | 55,883 psi | 90% | 3012 fps | 98.8% |
| Hodgdon H4350 | <<locked>> | 94% | 56,318 psi | 90% | 2979 fps | 97.9% |
| Hodgdon H4895 | <<locked>> | 82% | 55,114 psi | 88% | 2930 fps | 100% |
| Hodgdon Hybrid 100V | <<locked>> | 96% | 53,098 psi | 85% | 2923 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 86% | 55,376 psi | 89% | 2969 fps | 100% |
| Hodgdon Superformance | <<locked>> | 92% | 54,708 psi | 88% | 3025 fps | 98.5% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,114 psi | 58% | 1824 fps | 100% |
| Hodgdon VARGET | <<locked>> | 86% | 55,361 psi | 89% | 2920 fps | 100% |
| IMR 3031 | <<locked>> | 84% | 54,317 psi | 87% | 2890 fps | 100% |
| IMR 4064 | <<locked>> | 88% | 54,534 psi | 87% | 2897 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 88% | 53,548 psi | 86% | 2871 fps | 98.4% |
| IMR 4350 | <<locked>> | 94% | 54,027 psi | 87% | 2923 fps | 98.1% |
| IMR 4451 Enduron | <<locked>> | 90% | 54,969 psi | 88% | 2920 fps | 98.5% |
| IMR 4831 | <<locked>> | 98% | 53,388 psi | 86% | 2943 fps | 99.9% |
| IMR 4895 | <<locked>> | 84% | 54,462 psi | 87% | 2946 fps | 100% |
| IMR 4955 Enduronᴾ | <<locked>> | 100% | 56,362 psi | 90% | 2956 fps | 95.8% |
| Lovex D073.6 | <<locked>> | 82% | 54,824 psi | 88% | 2897 fps | 100% |
| Lovex S060 | <<locked>> | 82% | 53,592 psi | 86% | 2844 fps | 100% |
| Lovex S062 | <<locked>> | 86% | 55,303 psi | 89% | 2904 fps | 100% |
| Lovex S065 | <<locked>> | 92% | 54,897 psi | 88% | 2917 fps | 99.4% |
| Lovex S070 | <<locked>> | 94% | 55,985 psi | 90% | 2956 fps | 98.9% |
| Lovex S071ᴾ | <<locked>> | 100% | 41,191 psi | 66% | 2717 fps | 96.8% |
| Norma 201 | <<locked>> | 82% | 53,287 psi | 85% | 2864 fps | 100% |
| Norma 202 | <<locked>> | 82% | 53,853 psi | 86% | 2861 fps | 100% |
| Norma 203B | <<locked>> | 86% | 55,912 psi | 90% | 2956 fps | 100% |
| Norma 204 | <<locked>> | 94% | 54,476 psi | 87% | 2969 fps | 97% |
| Norma MRPᴾ | <<locked>> | 100% | 52,591 psi | 84% | 3041 fps | 98.4% |
| Norma URP | <<locked>> | 94% | 54,534 psi | 87% | 2979 fps | 99.9% |
| Ramshot Big Game | <<locked>> | 84% | 53,026 psi | 85% | 2930 fps | 100% |
| Ramshot Grandᴾ | <<locked>> | 100% | 56,028 psi | 90% | 3064 fps | 96.6% |
| Ramshot Hunter | <<locked>> | 94% | 53,229 psi | 85% | 2972 fps | 99.1% |
| Ramshot Magnumᴾ | <<locked>> | 100% | 48,472 psi | 78% | 2907 fps | 96.7% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 36,782 psi | 59% | 1870 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 86% | 54,230 psi | 87% | 2910 fps | 98.9% |
| ReloadSwiss RS 52 | <<locked>> | 82% | 53,780 psi | 86% | 2982 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 88% | 53,635 psi | 86% | 3018 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 94% | 55,695 psi | 89% | 3018 fps | 99.9% |
| ReloadSwiss RS 70 | <<locked>> | 94% | 54,215 psi | 87% | 3041 fps | 99.8% |
| Rottweil R 902 | <<locked>> | 84% | 54,041 psi | 87% | 2867 fps | 100% |
| Rottweil R 903 | <<locked>> | 88% | 53,548 psi | 86% | 2907 fps | 100% |
| Rottweil R 904 | <<locked>> | 98% | 55,100 psi | 88% | 2943 fps | 96.1% |
| Rottweil R 905ᴾ | <<locked>> | 100% | 55,143 psi | 88% | 3005 fps | 97.6% |
| Rottweil R 907 | <<locked>> | 90% | 53,330 psi | 86% | 2890 fps | 97.9% |
| Shooters World Long Rifle | <<locked>> | 92% | 54,897 psi | 88% | 2917 fps | 99.4% |
| Shooters World Match Rifle | <<locked>> | 82% | 54,824 psi | 88% | 2897 fps | 100% |
| Shooters World Precision | <<locked>> | 86% | 55,303 psi | 89% | 2904 fps | 100% |
| Shooters World SW4350 | <<locked>> | 94% | 55,985 psi | 90% | 2956 fps | 98.9% |
| SNPE Vectan SP 11 | <<locked>> | 88% | 55,230 psi | 89% | 2969 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 82% | 55,738 psi | 89% | 2923 fps | 99.8% |
| SNPE Vectan SP 9 | <<locked>> | 82% | 52,939 psi | 85% | 2890 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 82% | 54,273 psi | 87% | 2799 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 88% | 55,085 psi | 88% | 2802 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 92% | 54,592 psi | 88% | 2867 fps | 98.6% |
| SNPE Vectan Tubal 8000ᴾ | <<locked>> | 100% | 54,650 psi | 88% | 2999 fps | 97.5% |
| Somchem S335 | <<locked>> | 82% | 53,896 psi | 86% | 2795 fps | 100% |
| Somchem S341 | <<locked>> | 82% | 55,434 psi | 89% | 2913 fps | 100% |
| Somchem S355 | <<locked>> | 88% | 53,592 psi | 86% | 2904 fps | 100% |
| Somchem S365 | <<locked>> | 96% | 53,330 psi | 86% | 2982 fps | 100% |
| Somchem S385ᴾ | <<locked>> | 100% | 55,854 psi | 90% | 2979 fps | 98.4% |
| Unknown powder | <<locked>> | 92% | 55,288 psi | 89% | 2986 fps | 99.7% |
| Vihtavuori N133 | <<locked>> | 84% | 54,288 psi | 87% | 2779 fps | 100% |
| Vihtavuori N135 | <<locked>> | 84% | 54,201 psi | 87% | 2828 fps | 100% |
| Vihtavuori N140 | <<locked>> | 84% | 53,853 psi | 86% | 2835 fps | 100% |
| Vihtavuori N150 | <<locked>> | 94% | 55,143 psi | 88% | 2887 fps | 100% |
| Vihtavuori N160 | <<locked>> | 92% | 55,854 psi | 90% | 2956 fps | 99.9% |
| Vihtavuori N165ᴾ | <<locked>> | 100% | 46,557 psi | 75% | 2805 fps | 96.1% |
| Vihtavuori N540 | <<locked>> | 84% | 53,490 psi | 86% | 2861 fps | 100% |
| Vihtavuori N550 | <<locked>> | 92% | 56,057 psi | 90% | 3002 fps | 99.9% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 52,185 psi | 84% | 2979 fps | 100% |
| Winchester 6.5 StaBALL | <<locked>> | 92% | 52,837 psi | 85% | 2890 fps | 100% |
| Winchester 760 | <<locked>> | 90% | 55,883 psi | 90% | 3012 fps | 98.8% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 42,134 psi | 68% | 2943 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 98% | 54,273 psi | 87% | 2943 fps | 97.1% |
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% | 48,312 psi | 77% | 2743 fps | 100% |
| Accurate 2700 | <<locked>> | 80% | 41,872 psi | 67% | 2631 fps | 95% |
| Accurate 3100 | <<locked>> | 92% | 37,811 psi | 61% | 2648 fps | 95.8% |
| Accurate 4064 | <<locked>> | 80% | 45,716 psi | 73% | 2746 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 34,447 psi | 55% | 2585 fps | 96.4% |
| ADI AR 2206H | <<locked>> | 80% | 51,314 psi | 82% | 2867 fps | 100% |
| ADI AR 2208 | <<locked>> | 80% | 43,540 psi | 70% | 2713 fps | 99.1% |
| ADI AR 2209 | <<locked>> | 94% | 46,920 psi | 75% | 2854 fps | 95.3% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 47,456 psi | 76% | 2920 fps | 99.7% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 43,685 psi | 70% | 2740 fps | 99.8% |
| Alliant Reloder-15 | <<locked>> | 80% | 46,833 psi | 75% | 2808 fps | 99.6% |
| Alliant Reloder-16 | <<locked>> | 80% | 34,040 psi | 55% | 2595 fps | 96.5% |
| Alliant Reloder-17 | 60.3 gr | 80% | 38,232 psi | 61% | 2726 fps | 99.2% |
| Alliant Reloder-19 | <<locked>> | 94% | 46,166 psi | 74% | 2844 fps | 95.3% |
| Alliant Reloder-22 | <<locked>> | 98% | 46,456 psi | 74% | 2894 fps | 95.6% |
| Alliant Reloder-23 | <<locked>> | 84% | 28,079 psi | 45% | 2448 fps | 95.4% |
| Alliant Reloder-25 | <<locked>> | 96% | 36,085 psi | 58% | 2684 fps | 95.6% |
| Alliant Reloder-26 | <<locked>> | 88% | 34,650 psi | 56% | 2694 fps | 96% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 50,792 psi | 81% | 2877 fps | 99.7% |
| Bofors RP3 | <<locked>> | 80% | 43,874 psi | 70% | 2749 fps | 99.9% |
| Bofors RP5 | <<locked>> | 98% | 46,456 psi | 74% | 2894 fps | 95.6% |
| Bofors RP7 | <<locked>> | 82% | 41,423 psi | 66% | 2664 fps | 95.1% |
| Hodgdon H380 | <<locked>> | 80% | 44,338 psi | 71% | 2753 fps | 98.5% |
| Hodgdon H414 | <<locked>> | 80% | 39,653 psi | 64% | 2707 fps | 95.2% |
| Hodgdon H4350 | <<locked>> | 86% | 43,787 psi | 70% | 2749 fps | 95% |
| Hodgdon H4895 | <<locked>> | 80% | 51,837 psi | 83% | 2877 fps | 100% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 31,444 psi | 50% | 2493 fps | 97.2% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 45,397 psi | 73% | 2805 fps | 100% |
| Hodgdon Superformance | <<locked>> | 84% | 40,930 psi | 66% | 2762 fps | 95.1% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,021 psi | 43% | 1631 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 45,919 psi | 74% | 2762 fps | 99.9% |
| IMR 3031 | <<locked>> | 80% | 47,848 psi | 77% | 2795 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 42,786 psi | 69% | 2690 fps | 99.1% |
| IMR 4166 Enduron | <<locked>> | 80% | 42,061 psi | 67% | 2654 fps | 95.9% |
| IMR 4350 | <<locked>> | 86% | 41,887 psi | 67% | 2697 fps | 95.3% |
| IMR 4451 Enduron | <<locked>> | 80% | 40,335 psi | 65% | 2644 fps | 95.3% |
| IMR 4831 | <<locked>> | 82% | 32,169 psi | 52% | 2513 fps | 95.6% |
| IMR 4895 | <<locked>> | 80% | 48,051 psi | 77% | 2838 fps | 99.9% |
| IMR 4955 Enduron | <<locked>> | 98% | 53,026 psi | 85% | 2900 fps | 95% |
| Lovex D073.6 | <<locked>> | 80% | 51,213 psi | 82% | 2841 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 50,430 psi | 81% | 2795 fps | 100% |
| Lovex S062 | <<locked>> | 80% | 45,905 psi | 74% | 2749 fps | 100% |
| Lovex S065 | <<locked>> | 80% | 37,811 psi | 61% | 2592 fps | 96.1% |
| Lovex S070 | <<locked>> | 82% | 38,479 psi | 62% | 2625 fps | 95% |
| Lovex S071 | <<locked>> | 96% | 36,245 psi | 58% | 2612 fps | 95.2% |
| Norma 201 | <<locked>> | 80% | 50,096 psi | 80% | 2812 fps | 100% |
| Norma 202 | <<locked>> | 80% | 50,604 psi | 81% | 2812 fps | 100% |
| Norma 203B | <<locked>> | 80% | 46,209 psi | 74% | 2795 fps | 99.8% |
| Norma 204 | <<locked>> | 90% | 47,732 psi | 77% | 2851 fps | 95.5% |
| Norma MRP | <<locked>> | 92% | 39,929 psi | 64% | 2785 fps | 95% |
| Norma URP | <<locked>> | 80% | 34,345 psi | 55% | 2582 fps | 96.2% |
| Ramshot Big Game | <<locked>> | 80% | 46,180 psi | 74% | 2812 fps | 99.7% |
| Ramshot Grand | <<locked>> | 98% | 52,069 psi | 83% | 2995 fps | 95.6% |
| Ramshot Hunter | <<locked>> | 84% | 38,189 psi | 61% | 2680 fps | 95.7% |
| Ramshot Magnum | <<locked>> | 98% | 45,049 psi | 72% | 2841 fps | 95.7% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,340 psi | 44% | 1667 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 44,570 psi | 71% | 2736 fps | 97.2% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 50,111 psi | 80% | 2923 fps | 99.8% |
| ReloadSwiss RS 60 | 60.3 gr | 80% | 40,683 psi | 65% | 2789 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 34,026 psi | 55% | 2598 fps | 95.9% |
| ReloadSwiss RS 70 | 62.7 gr | 82% | 35,810 psi | 57% | 2661 fps | 95.9% |
| Rottweil R 902 | <<locked>> | 80% | 47,732 psi | 77% | 2766 fps | 100% |
| Rottweil R 903 | <<locked>> | 80% | 41,191 psi | 66% | 2690 fps | 99.5% |
| Rottweil R 904 | <<locked>> | 96% | 51,721 psi | 83% | 2887 fps | 95.4% |
| Rottweil R 905 | <<locked>> | 94% | 45,136 psi | 72% | 2825 fps | 95.2% |
| Rottweil R 907 | <<locked>> | 82% | 41,423 psi | 66% | 2664 fps | 95.1% |
| Shooters World Long Rifle | <<locked>> | 80% | 37,811 psi | 61% | 2592 fps | 96.1% |
| Shooters World Match Rifle | <<locked>> | 80% | 51,213 psi | 82% | 2841 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 45,905 psi | 74% | 2749 fps | 100% |
| Shooters World SW4350 | <<locked>> | 82% | 38,479 psi | 62% | 2625 fps | 95% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 42,250 psi | 68% | 2743 fps | 99.3% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 52,185 psi | 84% | 2867 fps | 99.5% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 49,617 psi | 80% | 2835 fps | 99.9% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 50,937 psi | 82% | 2749 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 42,902 psi | 69% | 2615 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 82% | 39,508 psi | 63% | 2589 fps | 95.2% |
| SNPE Vectan Tubal 8000 | <<locked>> | 94% | 44,701 psi | 72% | 2822 fps | 95.1% |
| Somchem S335 | <<locked>> | 80% | 50,734 psi | 81% | 2749 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 51,648 psi | 83% | 2854 fps | 100% |
| Somchem S355 | <<locked>> | 80% | 41,756 psi | 67% | 2694 fps | 99.5% |
| Somchem S365 | <<locked>> | 80% | 31,024 psi | 50% | 2539 fps | 98.4% |
| Somchem S385 | <<locked>> | 92% | 42,975 psi | 69% | 2753 fps | 95.6% |
| Unknown powder | <<locked>> | 80% | 37,275 psi | 60% | 2641 fps | 96.6% |
| Vihtavuori N133 | <<locked>> | 80% | 48,283 psi | 77% | 2690 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 47,659 psi | 76% | 2733 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 47,311 psi | 76% | 2736 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 35,737 psi | 57% | 2539 fps | 99.4% |
| Vihtavuori N160 | <<locked>> | 80% | 37,333 psi | 60% | 2618 fps | 97.2% |
| Vihtavuori N165 | <<locked>> | 98% | 43,453 psi | 70% | 2749 fps | 95.2% |
| Vihtavuori N540 | <<locked>> | 80% | 47,108 psi | 76% | 2759 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 37,782 psi | 61% | 2657 fps | 97.2% |
| Vihtavuori N555 | <<locked>> | 84% | 30,777 psi | 49% | 2530 fps | 95.6% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 35,128 psi | 56% | 2556 fps | 98.6% |
| Winchester 760 | <<locked>> | 80% | 39,653 psi | 64% | 2707 fps | 95.2% |
| Winchester StaBALL HD | <<locked>> | 88% | 28,297 psi | 45% | 2539 fps | 96.3% |
| Winchester Supreme 780 | <<locked>> | 94% | 47,021 psi | 75% | 2818 fps | 95.4% |
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 96 powders for .300 Win. Mag. loaded with the .307 | 165gr | Rhino Penetrator. Alliant Reloder-26 delivers the highest muzzle velocity at 3,091 fps; across all powders the maximum-charge window runs from 1,824 fps to 3,091 fps. Accurate 3100 gives the best case fill at 100 %, and 96 of the 96 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (430 MPa), the top charges use 58–90 %, leaving at least 10 % headroom. The 165.0 gr projectile in 0.307" calls for a 1:11.5 twist; slower twists will usually not stabilise this weight. Accurate 3100, Alliant Reloder-19, 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. ReloadSwiss RS 70, Alliant Reloder-17, ReloadSwiss RS 60 rank at the top here: for .300 Win. Mag. with the .307 | 165gr | Rhino Penetrator 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.