Load Specifications
Load data in caliber .300 Win. Mag. with .308 | 150gr | Lapua Mega bullet and 95 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.
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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>> | 82% | 55,434 psi | 89% | 2949 fps | 100% |
| Accurate 2495 | <<locked>> | 86% | 55,013 psi | 88% | 2979 fps | 100% |
| Accurate 2520 | <<locked>> | 82% | 56,202 psi | 90% | 3041 fps | 100% |
| Accurate 2700 | <<locked>> | 86% | 53,388 psi | 86% | 2969 fps | 96.7% |
| Accurate 3100ᴾ | <<locked>> | 100% | 45,672 psi | 73% | 2923 fps | 96.9% |
| Accurate 4064 | <<locked>> | 88% | 55,071 psi | 88% | 3028 fps | 100% |
| Accurate 4350 | <<locked>> | 96% | 55,143 psi | 88% | 3114 fps | 99.6% |
| ADI AR 2206H | <<locked>> | 84% | 54,897 psi | 88% | 3058 fps | 99.9% |
| ADI AR 2208 | <<locked>> | 90% | 55,883 psi | 90% | 3058 fps | 99.8% |
| ADI Benchmark 8208 | <<locked>> | 82% | 53,577 psi | 86% | 3002 fps | 100% |
| Alliant AR-Comp | <<locked>> | 82% | 54,853 psi | 88% | 2979 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 86% | 54,795 psi | 88% | 3182 fps | 99.9% |
| Alliant Power Pro Varmintᴾ | <<locked>> | 100% | 52,895 psi | 85% | 3084 fps | 95.8% |
| Alliant Reloder- TS 15.5 | <<locked>> | 90% | 56,130 psi | 90% | 3081 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 86% | 53,171 psi | 85% | 3048 fps | 99.7% |
| Alliant Reloder-16 | <<locked>> | 98% | 55,999 psi | 90% | 3176 fps | 99.9% |
| Alliant Reloder-17 | <<locked>> | 92% | 53,780 psi | 86% | 3153 fps | 100% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 43,294 psi | 69% | 2953 fps | 99.4% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 49,066 psi | 79% | 3136 fps | 99% |
| Baschieri & Pellagri 107 | <<locked>> | 84% | 54,708 psi | 88% | 3068 fps | 99.6% |
| Bofors RP3 | <<locked>> | 88% | 53,316 psi | 85% | 3041 fps | 100% |
| Bofors RP7 | <<locked>> | 92% | 53,316 psi | 85% | 3009 fps | 97% |
| Hodgdon Benchmark | <<locked>> | 82% | 55,056 psi | 88% | 2986 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 82% | 53,272 psi | 85% | 3031 fps | 100% |
| Hodgdon H380 | <<locked>> | 88% | 54,070 psi | 87% | 3051 fps | 99.2% |
| Hodgdon H414 | <<locked>> | 94% | 54,288 psi | 87% | 3110 fps | 97.8% |
| Hodgdon H4350 | <<locked>> | 92% | 54,607 psi | 88% | 3071 fps | 96.6% |
| Hodgdon H4895 | <<locked>> | 84% | 55,463 psi | 89% | 3071 fps | 100% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 56,260 psi | 90% | 3097 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 86% | 55,259 psi | 89% | 3104 fps | 100% |
| Hodgdon Superformance | <<locked>> | 94% | 54,665 psi | 88% | 3146 fps | 97.6% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 35,853 psi | 57% | 1909 fps | 100% |
| Hodgdon VARGET | <<locked>> | 84% | 53,127 psi | 85% | 3015 fps | 100% |
| IMR 3031 | <<locked>> | 84% | 55,564 psi | 89% | 3051 fps | 100% |
| IMR 4064 | <<locked>> | 88% | 55,376 psi | 89% | 3041 fps | 99.9% |
| IMR 4166 Enduron | <<locked>> | 86% | 54,984 psi | 88% | 3015 fps | 97.8% |
| IMR 4350 | <<locked>> | 96% | 53,954 psi | 87% | 3041 fps | 97.2% |
| IMR 4451 Enduron | <<locked>> | 92% | 54,969 psi | 88% | 3041 fps | 97.7% |
| IMR 4831 | <<locked>> | 98% | 55,637 psi | 89% | 3104 fps | 99.7% |
| IMR 4895 | <<locked>> | 86% | 54,563 psi | 87% | 3081 fps | 100% |
| IMR 8208 XBR | <<locked>> | 82% | 53,577 psi | 86% | 3002 fps | 100% |
| Lovex D073.6 | <<locked>> | 84% | 54,824 psi | 88% | 3031 fps | 100% |
| Lovex S060 | <<locked>> | 84% | 53,998 psi | 87% | 2979 fps | 99.9% |
| Lovex S062 | <<locked>> | 88% | 55,274 psi | 89% | 3035 fps | 100% |
| Lovex S065 | <<locked>> | 94% | 54,752 psi | 88% | 3038 fps | 98.8% |
| Lovex S070 | <<locked>> | 96% | 55,912 psi | 90% | 3077 fps | 98.2% |
| Norma 201 | <<locked>> | 84% | 53,461 psi | 86% | 2999 fps | 100% |
| Norma 202 | <<locked>> | 84% | 54,186 psi | 87% | 3002 fps | 100% |
| Norma 203B | <<locked>> | 88% | 56,028 psi | 90% | 3091 fps | 100% |
| Norma 204 | <<locked>> | 96% | 54,447 psi | 87% | 3087 fps | 95.9% |
| Norma MRPᴾ | <<locked>> | 100% | 48,559 psi | 78% | 3084 fps | 96.5% |
| Norma URP | <<locked>> | 96% | 54,128 psi | 87% | 3100 fps | 99.5% |
| Ramshot Big Game | <<locked>> | 86% | 53,098 psi | 85% | 3058 fps | 99.9% |
| Ramshot Hunter | <<locked>> | 96% | 52,910 psi | 85% | 3094 fps | 98.3% |
| Ramshot TAC | <<locked>> | 82% | 53,896 psi | 86% | 3018 fps | 98.8% |
| Ramshot Wild Boar | <<locked>> | 82% | 53,664 psi | 86% | 3038 fps | 99.9% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 36,245 psi | 58% | 1952 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 88% | 54,317 psi | 87% | 3035 fps | 98.2% |
| ReloadSwiss RS 52 | <<locked>> | 84% | 53,592 psi | 86% | 3114 fps | 99.7% |
| ReloadSwiss RS 60 | <<locked>> | 90% | 53,461 psi | 86% | 3153 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 96% | 55,143 psi | 88% | 3140 fps | 99.5% |
| ReloadSwiss RS 70 | <<locked>> | 96% | 54,201 psi | 87% | 3166 fps | 99.4% |
| Rottweil R 901 | <<locked>> | 82% | 54,302 psi | 87% | 2979 fps | 100% |
| Rottweil R 902 | <<locked>> | 86% | 54,201 psi | 87% | 2999 fps | 100% |
| Rottweil R 903 | <<locked>> | 90% | 53,432 psi | 86% | 3038 fps | 100% |
| Rottweil R 907 | <<locked>> | 92% | 53,316 psi | 85% | 3009 fps | 97% |
| Shooters World Long Rifle | <<locked>> | 94% | 54,752 psi | 88% | 3038 fps | 98.8% |
| Shooters World Match Rifle | <<locked>> | 84% | 54,824 psi | 88% | 3031 fps | 100% |
| Shooters World Precision | <<locked>> | 88% | 55,274 psi | 89% | 3035 fps | 100% |
| Shooters World SW4350 | <<locked>> | 96% | 55,912 psi | 90% | 3077 fps | 98.2% |
| SNPE Vectan SP 11 | <<locked>> | 90% | 55,013 psi | 88% | 3097 fps | 99.9% |
| SNPE Vectan SP 7 | <<locked>> | 84% | 56,115 psi | 90% | 3054 fps | 99.4% |
| SNPE Vectan SP 9 | <<locked>> | 84% | 53,171 psi | 85% | 3022 fps | 99.9% |
| SNPE Vectan Tubal 3000 | <<locked>> | 84% | 54,810 psi | 88% | 2936 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 90% | 55,332 psi | 89% | 2933 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 94% | 54,766 psi | 88% | 2986 fps | 97.8% |
| Somchem S335 | <<locked>> | 84% | 54,201 psi | 87% | 2930 fps | 100% |
| Somchem S341 | <<locked>> | 84% | 55,724 psi | 89% | 3045 fps | 100% |
| Somchem S355 | <<locked>> | 90% | 53,650 psi | 86% | 3035 fps | 100% |
| Somchem S365ᴾ | <<locked>> | 100% | 56,130 psi | 90% | 3159 fps | 100% |
| Somchem S385ᴾ | <<locked>> | 100% | 51,880 psi | 83% | 3031 fps | 96.7% |
| Vihtavuori N133 | <<locked>> | 84% | 55,172 psi | 88% | 2920 fps | 100% |
| Vihtavuori N135 | <<locked>> | 86% | 53,983 psi | 87% | 2963 fps | 100% |
| Vihtavuori N140 | <<locked>> | 86% | 54,607 psi | 88% | 2979 fps | 100% |
| Vihtavuori N150 | <<locked>> | 92% | 54,926 psi | 88% | 3009 fps | 100% |
| Vihtavuori N160 | <<locked>> | 96% | 56,434 psi | 90% | 3097 fps | 99.6% |
| Vihtavuori N530 | <<locked>> | 82% | 54,128 psi | 87% | 3002 fps | 100% |
| Vihtavuori N540 | <<locked>> | 88% | 56,304 psi | 90% | 3022 fps | 100% |
| Vihtavuori N550 | <<locked>> | 96% | 55,506 psi | 89% | 3100 fps | 99.5% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 47,935 psi | 77% | 3031 fps | 99.3% |
| Winchester 6.5 StaBALL | <<locked>> | 94% | 53,011 psi | 85% | 3015 fps | 100% |
| Winchester 748 | <<locked>> | 82% | 54,302 psi | 87% | 3051 fps | 100% |
| Winchester 760 | <<locked>> | 94% | 54,288 psi | 87% | 3110 fps | 97.8% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 38,841 psi | 62% | 2969 fps | 99.5% |
| Winchester StaBALL Match | <<locked>> | 84% | 53,258 psi | 85% | 3031 fps | 100% |
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% | 52,069 psi | 83% | 2897 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 45,078 psi | 72% | 2825 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 52,518 psi | 84% | 2986 fps | 100% |
| Accurate 2700 | <<locked>> | 82% | 46,833 psi | 75% | 2851 fps | 95.2% |
| Accurate 3100 | <<locked>> | 96% | 39,755 psi | 64% | 2799 fps | 95.2% |
| Accurate 4064 | <<locked>> | 80% | 42,641 psi | 68% | 2818 fps | 100% |
| Accurate 4350 | <<locked>> | 82% | 33,910 psi | 54% | 2684 fps | 95% |
| ADI AR 2206H | <<locked>> | 80% | 48,341 psi | 78% | 2943 fps | 99.5% |
| ADI AR 2208 | <<locked>> | 80% | 41,046 psi | 66% | 2779 fps | 97.9% |
| ADI Benchmark 8208 | <<locked>> | 80% | 50,386 psi | 81% | 2949 fps | 100% |
| Alliant AR-Comp | <<locked>> | 80% | 51,358 psi | 82% | 2930 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 44,266 psi | 71% | 2979 fps | 98.6% |
| Alliant Power Pro Varmint | <<locked>> | 98% | 49,734 psi | 80% | 3022 fps | 95% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 40,915 psi | 66% | 2802 fps | 99.1% |
| Alliant Reloder-15 | <<locked>> | 80% | 43,932 psi | 70% | 2874 fps | 98.6% |
| Alliant Reloder-16 | <<locked>> | 82% | 33,895 psi | 54% | 2700 fps | 95% |
| Alliant Reloder-17 | 60.7 gr | 80% | 35,563 psi | 57% | 2772 fps | 97.6% |
| Alliant Reloder-23 | <<locked>> | 90% | 31,531 psi | 51% | 2654 fps | 95.8% |
| Alliant Reloder-26 | <<locked>> | 92% | 36,651 psi | 59% | 2854 fps | 95.4% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 47,819 psi | 77% | 2946 fps | 98.9% |
| Bofors RP3 | <<locked>> | 80% | 40,872 psi | 66% | 2808 fps | 99.1% |
| Bofors RP7 | <<locked>> | 88% | 47,108 psi | 76% | 2897 fps | 95.5% |
| Hodgdon Benchmark | <<locked>> | 80% | 51,851 psi | 83% | 2933 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 80% | 49,632 psi | 80% | 2972 fps | 100% |
| Hodgdon H380 | <<locked>> | 80% | 41,481 psi | 67% | 2812 fps | 97% |
| Hodgdon H414 | <<locked>> | 88% | 44,338 psi | 71% | 2923 fps | 95.5% |
| Hodgdon H4350 | <<locked>> | 90% | 51,097 psi | 82% | 3009 fps | 95.8% |
| Hodgdon H4895 | <<locked>> | 80% | 48,820 psi | 78% | 2953 fps | 99.8% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 29,269 psi | 47% | 2533 fps | 95% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 44,918 psi | 72% | 2923 fps | 99.7% |
| Hodgdon Superformance | <<locked>> | 90% | 47,311 psi | 76% | 3009 fps | 95.8% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,687 psi | 43% | 1706 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 46,731 psi | 75% | 2900 fps | 99.6% |
| IMR 3031 | <<locked>> | 80% | 48,747 psi | 78% | 2943 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 43,134 psi | 69% | 2818 fps | 98.5% |
| IMR 4166 Enduron | <<locked>> | 80% | 45,426 psi | 73% | 2838 fps | 95.7% |
| IMR 4350 | <<locked>> | 92% | 47,529 psi | 76% | 2923 fps | 95.7% |
| IMR 4451 Enduron | <<locked>> | 86% | 45,905 psi | 74% | 2874 fps | 95.7% |
| IMR 4831 | <<locked>> | 84% | 35,215 psi | 56% | 2703 fps | 95.6% |
| IMR 4895 | <<locked>> | 80% | 45,049 psi | 72% | 2907 fps | 99.2% |
| IMR 8208 XBR | <<locked>> | 80% | 50,386 psi | 81% | 2949 fps | 100% |
| Lovex D073.6 | <<locked>> | 80% | 47,848 psi | 77% | 2920 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 47,834 psi | 77% | 2871 fps | 99.5% |
| Lovex S062 | <<locked>> | 80% | 43,120 psi | 69% | 2818 fps | 99.6% |
| Lovex S065 | <<locked>> | 84% | 40,147 psi | 64% | 2756 fps | 95.7% |
| Lovex S070 | <<locked>> | 88% | 43,526 psi | 70% | 2848 fps | 95.5% |
| Norma 201 | <<locked>> | 80% | 47,195 psi | 76% | 2887 fps | 99.9% |
| Norma 202 | <<locked>> | 80% | 47,616 psi | 76% | 2894 fps | 100% |
| Norma 203B | <<locked>> | 80% | 43,323 psi | 69% | 2861 fps | 98.9% |
| Norma 204 | <<locked>> | 94% | 50,865 psi | 82% | 3025 fps | 95.1% |
| Norma MRP | <<locked>> | 98% | 45,353 psi | 73% | 3018 fps | 95.6% |
| Norma URP | <<locked>> | 84% | 36,477 psi | 58% | 2746 fps | 95.9% |
| Ramshot Big Game | <<locked>> | 80% | 43,004 psi | 69% | 2874 fps | 98.7% |
| Ramshot Hunter | <<locked>> | 88% | 40,524 psi | 65% | 2848 fps | 95.3% |
| Ramshot TAC | <<locked>> | 80% | 50,372 psi | 81% | 2956 fps | 98.3% |
| Ramshot Wild Boar | <<locked>> | 80% | 50,067 psi | 80% | 2979 fps | 99.7% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,108 psi | 43% | 1749 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 41,829 psi | 67% | 2795 fps | 95.4% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 46,818 psi | 75% | 2992 fps | 99% |
| ReloadSwiss RS 60 | 60.7 gr | 80% | 37,826 psi | 61% | 2844 fps | 99.8% |
| ReloadSwiss RS 62 | <<locked>> | 84% | 36,172 psi | 58% | 2762 fps | 95.5% |
| ReloadSwiss RS 70 | 66.3 gr | 86% | 38,421 psi | 62% | 2835 fps | 95.6% |
| Rottweil R 901 | <<locked>> | 80% | 51,314 psi | 82% | 2933 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 44,991 psi | 72% | 2838 fps | 99.7% |
| Rottweil R 903 | <<locked>> | 80% | 38,377 psi | 62% | 2749 fps | 98.5% |
| Rottweil R 907 | <<locked>> | 88% | 47,108 psi | 76% | 2897 fps | 95.5% |
| Shooters World Long Rifle | <<locked>> | 84% | 40,147 psi | 64% | 2756 fps | 95.7% |
| Shooters World Match Rifle | <<locked>> | 80% | 47,848 psi | 77% | 2920 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 43,120 psi | 69% | 2818 fps | 99.6% |
| Shooters World SW4350 | <<locked>> | 88% | 43,526 psi | 70% | 2848 fps | 95.5% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 39,537 psi | 63% | 2805 fps | 98.1% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 48,921 psi | 78% | 2933 fps | 98.5% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 46,862 psi | 75% | 2910 fps | 99.4% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 48,298 psi | 77% | 2835 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 40,451 psi | 65% | 2690 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 88% | 45,165 psi | 72% | 2815 fps | 95.7% |
| Somchem S335 | <<locked>> | 80% | 48,037 psi | 77% | 2835 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 48,689 psi | 78% | 2930 fps | 99.5% |
| Somchem S355 | <<locked>> | 80% | 39,059 psi | 63% | 2753 fps | 98.4% |
| Somchem S365 | <<locked>> | 80% | 28,572 psi | 46% | 2569 fps | 96.2% |
| Somchem S385 | <<locked>> | 96% | 45,455 psi | 73% | 2913 fps | 95.1% |
| Vihtavuori N133 | <<locked>> | 80% | 48,718 psi | 78% | 2825 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 44,657 psi | 72% | 2815 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 45,121 psi | 72% | 2825 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 37,159 psi | 60% | 2684 fps | 99% |
| Vihtavuori N160 | <<locked>> | 82% | 35,549 psi | 57% | 2690 fps | 95.5% |
| Vihtavuori N530 | <<locked>> | 80% | 50,604 psi | 81% | 2943 fps | 100% |
| Vihtavuori N540 | <<locked>> | 80% | 43,555 psi | 70% | 2812 fps | 100% |
| Vihtavuori N550 | <<locked>> | 82% | 35,085 psi | 56% | 2690 fps | 95% |
| Vihtavuori N555 | <<locked>> | 88% | 32,097 psi | 51% | 2677 fps | 95% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 32,996 psi | 53% | 2605 fps | 96.9% |
| Winchester 748 | <<locked>> | 80% | 50,807 psi | 81% | 2995 fps | 100% |
| Winchester 760 | <<locked>> | 88% | 44,556 psi | 71% | 2927 fps | 95.6% |
| Winchester StaBALL HD | <<locked>> | 92% | 29,791 psi | 48% | 2677 fps | 95.4% |
| Winchester StaBALL Match | <<locked>> | 80% | 46,427 psi | 74% | 2913 fps | 99.6% |
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 95 powders for .300 Win. Mag. loaded with the .308 | 150gr | Lapua Mega. Alliant Power Pro 2000-MR delivers the highest muzzle velocity at 3,182 fps; across all powders the maximum-charge window runs from 1,909 fps to 3,182 fps. Accurate 3100 gives the best case fill at 100 %, and 95 of the 95 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (430 MPa), the top charges use 57–90 %, leaving at least 10 % headroom. The 150.0 gr projectile in 0.308" calls for a 1:11.5 twist; slower twists will usually not stabilise this weight. Accurate 3100, Alliant Power Pro Varmint, Alliant Reloder-23 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 .308 | 150gr | Lapua Mega 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.