Load Specifications
Load data in caliber .300 Win. Mag. with .308 | 136gr | Geco ZERO 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 60, Alliant Reloder-17 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.
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 2015 | <<locked>> | 84% | 55,666 psi | 89% | 3104 fps | 100% |
| Accurate 2495 | <<locked>> | 88% | 54,331 psi | 87% | 3123 fps | 100% |
| Accurate 2520 | <<locked>> | 84% | 54,665 psi | 88% | 3179 fps | 100% |
| Accurate 2700 | <<locked>> | 92% | 55,216 psi | 89% | 3120 fps | 96.3% |
| Accurate 4064 | <<locked>> | 90% | 54,346 psi | 87% | 3173 fps | 100% |
| Accurate 4350 | <<locked>> | 98% | 54,766 psi | 88% | 3255 fps | 99.2% |
| ADI AR 2206H | <<locked>> | 86% | 55,042 psi | 88% | 3209 fps | 99.7% |
| ADI AR 2208 | <<locked>> | 92% | 56,376 psi | 90% | 3209 fps | 99.6% |
| ADI Benchmark 8208 | <<locked>> | 84% | 53,969 psi | 87% | 3156 fps | 100% |
| Alliant AR-Comp | <<locked>> | 84% | 54,984 psi | 88% | 3136 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 88% | 55,187 psi | 88% | 3333 fps | 99.6% |
| Alliant Reloder- TS 15.5 | <<locked>> | 92% | 56,159 psi | 90% | 3228 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 88% | 53,287 psi | 85% | 3192 fps | 99.4% |
| Alliant Reloder-16ᴾ | <<locked>> | 100% | 56,188 psi | 90% | 3323 fps | 99.6% |
| Alliant Reloder-17 | <<locked>> | 94% | 53,925 psi | 86% | 3301 fps | 100% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 39,972 psi | 64% | 3005 fps | 98.1% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 45,150 psi | 72% | 3186 fps | 97.4% |
| Baschieri & Pellagri 107 | <<locked>> | 86% | 55,172 psi | 88% | 3222 fps | 99.3% |
| Bofors RP3 | <<locked>> | 90% | 53,243 psi | 85% | 3186 fps | 99.9% |
| Bofors RP7 | <<locked>> | 94% | 53,592 psi | 86% | 3150 fps | 96.1% |
| Hodgdon Benchmark | <<locked>> | 84% | 55,521 psi | 89% | 3140 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 84% | 53,461 psi | 86% | 3182 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 82% | 55,477 psi | 89% | 3291 fps | 99.6% |
| Hodgdon H322 | <<locked>> | 82% | 53,838 psi | 86% | 3143 fps | 100% |
| Hodgdon H380 | <<locked>> | 90% | 54,215 psi | 87% | 3199 fps | 98.8% |
| Hodgdon H414 | <<locked>> | 94% | 55,898 psi | 90% | 3278 fps | 97.3% |
| Hodgdon H4350 | <<locked>> | 98% | 56,420 psi | 90% | 3241 fps | 96% |
| Hodgdon H4895 | <<locked>> | 86% | 55,622 psi | 89% | 3222 fps | 99.9% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 52,388 psi | 84% | 3182 fps | 99.8% |
| Hodgdon LEVERevolution | <<locked>> | 90% | 55,347 psi | 89% | 3251 fps | 100% |
| Hodgdon Superformance | <<locked>> | 96% | 55,027 psi | 88% | 3284 fps | 96.8% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 35,404 psi | 57% | 2011 fps | 100% |
| Hodgdon VARGET | <<locked>> | 90% | 55,854 psi | 90% | 3205 fps | 99.9% |
| IMR 3031 | <<locked>> | 88% | 54,027 psi | 87% | 3182 fps | 100% |
| IMR 4064 | <<locked>> | 92% | 54,940 psi | 88% | 3179 fps | 99.6% |
| IMR 4166 Enduron | <<locked>> | 92% | 54,346 psi | 87% | 3143 fps | 96.9% |
| IMR 4350 | <<locked>> | 98% | 53,925 psi | 86% | 3176 fps | 96.3% |
| IMR 4451 Enduron | <<locked>> | 94% | 55,506 psi | 89% | 3189 fps | 97% |
| IMR 4831ᴾ | <<locked>> | 100% | 49,211 psi | 79% | 3136 fps | 98.5% |
| IMR 4895 | <<locked>> | 88% | 54,679 psi | 88% | 3228 fps | 99.8% |
| IMR 8208 XBR | <<locked>> | 84% | 53,969 psi | 87% | 3156 fps | 100% |
| Lovex D073.6 | <<locked>> | 86% | 54,665 psi | 88% | 3179 fps | 100% |
| Lovex S060 | <<locked>> | 86% | 54,418 psi | 87% | 3130 fps | 99.7% |
| Lovex S062 | <<locked>> | 90% | 55,492 psi | 89% | 3186 fps | 100% |
| Lovex S065 | <<locked>> | 96% | 54,795 psi | 88% | 3179 fps | 98.2% |
| Lovex S070 | <<locked>> | 98% | 55,956 psi | 90% | 3215 fps | 97.5% |
| Norma 201 | <<locked>> | 86% | 53,592 psi | 86% | 3146 fps | 100% |
| Norma 202 | <<locked>> | 86% | 54,186 psi | 87% | 3150 fps | 100% |
| Norma 203B | <<locked>> | 90% | 56,072 psi | 90% | 3241 fps | 99.8% |
| Norma URP | <<locked>> | 98% | 54,114 psi | 87% | 3245 fps | 99.1% |
| Ramshot Big Game | <<locked>> | 88% | 53,272 psi | 85% | 3205 fps | 99.6% |
| Ramshot Hunter | <<locked>> | 98% | 52,852 psi | 85% | 3228 fps | 97.6% |
| Ramshot TAC | <<locked>> | 84% | 54,346 psi | 87% | 3169 fps | 98.3% |
| Ramshot Wild Boar | <<locked>> | 84% | 54,056 psi | 87% | 3192 fps | 99.7% |
| Ramshot X-Terminator | <<locked>> | 82% | 54,752 psi | 88% | 3153 fps | 99.7% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 35,665 psi | 57% | 2054 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 90% | 54,723 psi | 88% | 3179 fps | 97.6% |
| ReloadSwiss RS 52 | <<locked>> | 86% | 53,766 psi | 86% | 3264 fps | 99.4% |
| ReloadSwiss RS 60 | <<locked>> | 92% | 53,505 psi | 86% | 3304 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 98% | 54,766 psi | 88% | 3274 fps | 99% |
| ReloadSwiss RS 70 | <<locked>> | 98% | 54,476 psi | 87% | 3307 fps | 98.8% |
| Rottweil R 901 | <<locked>> | 84% | 54,331 psi | 87% | 3133 fps | 100% |
| Rottweil R 902 | <<locked>> | 88% | 54,041 psi | 87% | 3146 fps | 100% |
| Rottweil R 903 | <<locked>> | 92% | 53,098 psi | 85% | 3176 fps | 99.9% |
| Rottweil R 907 | <<locked>> | 94% | 53,592 psi | 86% | 3150 fps | 96.1% |
| Shooters World Long Rifle | <<locked>> | 96% | 54,795 psi | 88% | 3179 fps | 98.2% |
| Shooters World Match Rifle | <<locked>> | 86% | 54,665 psi | 88% | 3179 fps | 100% |
| Shooters World Precision | <<locked>> | 90% | 55,492 psi | 89% | 3186 fps | 100% |
| Shooters World SW4350 | <<locked>> | 98% | 55,956 psi | 90% | 3215 fps | 97.5% |
| SNPE Vectan SP 11 | <<locked>> | 92% | 55,201 psi | 89% | 3245 fps | 99.8% |
| SNPE Vectan SP 7 | <<locked>> | 84% | 52,736 psi | 85% | 3143 fps | 98.4% |
| SNPE Vectan SP 9 | <<locked>> | 86% | 53,606 psi | 86% | 3173 fps | 99.7% |
| SNPE Vectan Tubal 3000 | <<locked>> | 86% | 55,143 psi | 88% | 3091 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 92% | 55,521 psi | 89% | 3084 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 96% | 55,172 psi | 88% | 3127 fps | 97.1% |
| Somchem S321 | <<locked>> | 82% | 55,332 psi | 89% | 3189 fps | 100% |
| Somchem S335 | <<locked>> | 86% | 54,505 psi | 87% | 3084 fps | 100% |
| Somchem S341 | <<locked>> | 86% | 56,246 psi | 90% | 3199 fps | 99.8% |
| Somchem S355 | <<locked>> | 92% | 53,563 psi | 86% | 3176 fps | 99.8% |
| Somchem S365ᴾ | <<locked>> | 100% | 52,011 psi | 83% | 3241 fps | 100% |
| Unknown powder | <<locked>> | 96% | 55,187 psi | 88% | 3255 fps | 98.8% |
| Vihtavuori N130 | <<locked>> | 82% | 53,606 psi | 86% | 3038 fps | 100% |
| Vihtavuori N133 | <<locked>> | 88% | 54,781 psi | 88% | 3071 fps | 100% |
| Vihtavuori N135 | <<locked>> | 88% | 53,911 psi | 86% | 3114 fps | 100% |
| Vihtavuori N140 | <<locked>> | 88% | 54,085 psi | 87% | 3120 fps | 100% |
| Vihtavuori N150 | <<locked>> | 98% | 54,940 psi | 88% | 3159 fps | 100% |
| Vihtavuori N160 | <<locked>> | 96% | 55,593 psi | 89% | 3222 fps | 99.2% |
| Vihtavuori N530 | <<locked>> | 82% | 53,447 psi | 86% | 3159 fps | 100% |
| Vihtavuori N540 | <<locked>> | 88% | 53,853 psi | 86% | 3146 fps | 100% |
| Vihtavuori N550 | <<locked>> | 96% | 55,898 psi | 90% | 3271 fps | 99.2% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 44,077 psi | 71% | 3094 fps | 98% |
| Winchester 6.5 StaBALL | <<locked>> | 96% | 53,359 psi | 86% | 3159 fps | 99.9% |
| Winchester 748 | <<locked>> | 82% | 55,216 psi | 89% | 3219 fps | 100% |
| Winchester 760 | <<locked>> | 94% | 55,898 psi | 90% | 3278 fps | 97.3% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 35,839 psi | 57% | 2992 fps | 97.7% |
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% | 48,921 psi | 78% | 2999 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 41,263 psi | 66% | 2900 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 47,543 psi | 76% | 3058 fps | 100% |
| Accurate 2700 | <<locked>> | 90% | 51,517 psi | 83% | 3058 fps | 95.4% |
| Accurate 4064 | <<locked>> | 80% | 39,044 psi | 63% | 2887 fps | 99.9% |
| Accurate 4350 | <<locked>> | 88% | 38,319 psi | 61% | 2923 fps | 95.6% |
| ADI AR 2206H | <<locked>> | 80% | 45,252 psi | 73% | 3025 fps | 98.6% |
| ADI AR 2208 | <<locked>> | 80% | 38,508 psi | 62% | 2854 fps | 96.3% |
| ADI Benchmark 8208 | <<locked>> | 80% | 47,413 psi | 76% | 3038 fps | 99.6% |
| Alliant AR-Comp | <<locked>> | 80% | 47,950 psi | 77% | 3031 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 41,379 psi | 66% | 3048 fps | 97% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 37,971 psi | 61% | 2871 fps | 97.8% |
| Alliant Reloder-15 | <<locked>> | 80% | 40,901 psi | 66% | 2946 fps | 97.2% |
| Alliant Reloder-16 | <<locked>> | 88% | 38,218 psi | 61% | 2943 fps | 95.7% |
| Alliant Reloder-17 | 62.6 gr | 80% | 32,866 psi | 53% | 2818 fps | 95.4% |
| Alliant Reloder-23 | <<locked>> | 94% | 32,895 psi | 53% | 2815 fps | 95.3% |
| Alliant Reloder-26 | <<locked>> | 96% | 38,928 psi | 62% | 3031 fps | 95.2% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 44,860 psi | 72% | 3028 fps | 97.7% |
| Bofors RP3 | <<locked>> | 80% | 37,724 psi | 60% | 2874 fps | 97.8% |
| Bofors RP7 | <<locked>> | 92% | 50,169 psi | 80% | 3087 fps | 95.3% |
| Hodgdon Benchmark | <<locked>> | 80% | 49,095 psi | 79% | 3028 fps | 99.9% |
| Hodgdon BL-C2 | <<locked>> | 80% | 46,456 psi | 74% | 3058 fps | 99.8% |
| Hodgdon CFE223 | <<locked>> | 80% | 51,648 psi | 83% | 3222 fps | 99.2% |
| Hodgdon H322 | <<locked>> | 80% | 50,531 psi | 81% | 3091 fps | 100% |
| Hodgdon H380 | <<locked>> | 80% | 38,566 psi | 62% | 2874 fps | 95.1% |
| Hodgdon H414 | <<locked>> | 90% | 48,457 psi | 78% | 3140 fps | 95.7% |
| Hodgdon H4350 | <<locked>> | 96% | 52,866 psi | 85% | 3176 fps | 95.2% |
| Hodgdon H4895 | <<locked>> | 80% | 45,687 psi | 73% | 3035 fps | 99.1% |
| Hodgdon Hybrid 100V | <<locked>> | 86% | 32,793 psi | 53% | 2759 fps | 95.5% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 39,320 psi | 63% | 2940 fps | 98.2% |
| Hodgdon Superformance | <<locked>> | 94% | 51,198 psi | 82% | 3215 fps | 95.8% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,165 psi | 42% | 1798 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 40,669 psi | 65% | 2910 fps | 98.1% |
| IMR 3031 | <<locked>> | 80% | 41,495 psi | 67% | 2959 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 37,594 psi | 60% | 2825 fps | 96.3% |
| IMR 4166 Enduron | <<locked>> | 88% | 48,008 psi | 77% | 3025 fps | 95.4% |
| IMR 4350 | <<locked>> | 96% | 50,778 psi | 81% | 3117 fps | 95.6% |
| IMR 4451 Enduron | <<locked>> | 90% | 49,023 psi | 79% | 3071 fps | 95.6% |
| IMR 4831 | <<locked>> | 92% | 37,898 psi | 61% | 2894 fps | 95.6% |
| IMR 4895 | <<locked>> | 80% | 41,916 psi | 67% | 2979 fps | 98% |
| IMR 8208 XBR | <<locked>> | 80% | 47,413 psi | 76% | 3038 fps | 99.6% |
| Lovex D073.6 | <<locked>> | 80% | 44,425 psi | 71% | 2999 fps | 99.9% |
| Lovex S060 | <<locked>> | 80% | 45,223 psi | 73% | 2959 fps | 98.7% |
| Lovex S062 | <<locked>> | 80% | 40,190 psi | 64% | 2894 fps | 98.7% |
| Lovex S065 | <<locked>> | 88% | 42,641 psi | 68% | 2943 fps | 95.5% |
| Lovex S070 | <<locked>> | 92% | 45,977 psi | 74% | 3031 fps | 95.2% |
| Norma 201 | <<locked>> | 80% | 44,106 psi | 71% | 2969 fps | 99.3% |
| Norma 202 | <<locked>> | 80% | 44,541 psi | 71% | 2982 fps | 100% |
| Norma 203B | <<locked>> | 80% | 40,248 psi | 65% | 2930 fps | 97.6% |
| Norma URP | <<locked>> | 88% | 38,580 psi | 62% | 2927 fps | 95.6% |
| Ramshot Big Game | <<locked>> | 80% | 40,074 psi | 64% | 2946 fps | 97.3% |
| Ramshot Hunter | <<locked>> | 92% | 43,134 psi | 69% | 3035 fps | 95.1% |
| Ramshot TAC | <<locked>> | 80% | 47,514 psi | 76% | 3038 fps | 97% |
| Ramshot Wild Boar | <<locked>> | 80% | 47,065 psi | 75% | 3061 fps | 98.9% |
| Ramshot X-Terminator | <<locked>> | 80% | 51,213 psi | 82% | 3091 fps | 99.4% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 26,484 psi | 42% | 1837 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 84% | 44,657 psi | 72% | 2989 fps | 95.2% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 43,453 psi | 70% | 3064 fps | 97.7% |
| ReloadSwiss RS 60 | 62.6 gr | 80% | 35,027 psi | 56% | 2900 fps | 98.7% |
| ReloadSwiss RS 62 | <<locked>> | 88% | 38,174 psi | 61% | 2940 fps | 95.2% |
| ReloadSwiss RS 70 | 71.6 gr | 90% | 41,104 psi | 66% | 3022 fps | 95.4% |
| Rottweil R 901 | <<locked>> | 80% | 47,892 psi | 77% | 3022 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 42,003 psi | 67% | 2917 fps | 99% |
| Rottweil R 903 | <<locked>> | 80% | 35,389 psi | 57% | 2808 fps | 96.8% |
| Rottweil R 907 | <<locked>> | 92% | 50,169 psi | 80% | 3087 fps | 95.3% |
| Shooters World Long Rifle | <<locked>> | 88% | 42,641 psi | 68% | 2943 fps | 95.5% |
| Shooters World Match Rifle | <<locked>> | 80% | 44,425 psi | 71% | 2999 fps | 99.9% |
| Shooters World Precision | <<locked>> | 80% | 40,190 psi | 64% | 2894 fps | 98.7% |
| Shooters World SW4350 | <<locked>> | 92% | 45,977 psi | 74% | 3031 fps | 95.2% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 36,622 psi | 59% | 2864 fps | 96.3% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 45,774 psi | 73% | 3009 fps | 97.1% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 43,932 psi | 70% | 2989 fps | 98.4% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 45,629 psi | 73% | 2930 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 37,956 psi | 61% | 2776 fps | 99.9% |
| SNPE Vectan Tubal 7000 | <<locked>> | 92% | 48,225 psi | 77% | 3002 fps | 95.5% |
| Somchem S321 | <<locked>> | 80% | 51,648 psi | 83% | 3127 fps | 100% |
| Somchem S335 | <<locked>> | 80% | 45,136 psi | 72% | 2927 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 45,629 psi | 73% | 3009 fps | 98.6% |
| Somchem S355 | <<locked>> | 80% | 36,172 psi | 58% | 2818 fps | 96.9% |
| Somchem S365 | <<locked>> | 84% | 30,023 psi | 48% | 2736 fps | 95.8% |
| Unknown powder | <<locked>> | 86% | 39,233 psi | 63% | 2933 fps | 95% |
| Vihtavuori N130 | <<locked>> | 80% | 50,401 psi | 81% | 2989 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 42,844 psi | 69% | 2871 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 41,640 psi | 67% | 2904 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 41,611 psi | 67% | 2900 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 30,734 psi | 49% | 2651 fps | 96.4% |
| Vihtavuori N160 | <<locked>> | 86% | 39,363 psi | 63% | 2907 fps | 95.8% |
| Vihtavuori N530 | <<locked>> | 80% | 49,951 psi | 80% | 3097 fps | 99.9% |
| Vihtavuori N540 | <<locked>> | 80% | 41,452 psi | 66% | 2920 fps | 99.9% |
| Vihtavuori N550 | <<locked>> | 86% | 39,871 psi | 64% | 2949 fps | 95.8% |
| Vihtavuori N555 | <<locked>> | 94% | 35,781 psi | 57% | 2904 fps | 95.5% |
| Winchester 6.5 StaBALL | <<locked>> | 82% | 32,880 psi | 53% | 2720 fps | 95.8% |
| Winchester 748 | <<locked>> | 80% | 51,459 psi | 83% | 3156 fps | 100% |
| Winchester 760 | <<locked>> | 90% | 48,457 psi | 78% | 3140 fps | 95.7% |
| Winchester StaBALL HD | <<locked>> | 98% | 33,402 psi | 54% | 2910 fps | 96.3% |
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 112 powders for .300 Win. Mag. loaded with the .308 | 136gr | Geco ZERO. Alliant Power Pro 2000-MR delivers the highest muzzle velocity at 3,333 fps; across all powders the maximum-charge window runs from 2,011 fps to 3,333 fps. Accurate 3100 gives the best case fill at 100 %, and 112 of the 112 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (430 MPa), the top charges use 55–90 %, leaving at least 10 % headroom. The 136.0 gr projectile in 0.308" calls for a 1:12.5 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. ReloadSwiss RS 60, Alliant Reloder-17, ReloadSwiss RS 70 rank at the top here: for .300 Win. Mag. with the .308 | 136gr | Geco ZERO they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, Accurate 3100, ADI AR 2209, Alliant Reloder-19 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.