Load Specifications
Load data in caliber .300 Win. Mag. with .308 | 146gr | Peregrine Glider (Glider GRM) 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, 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>> | 82% | 53,490 psi | 86% | 2969 fps | 100% |
| Accurate 2495 | <<locked>> | 88% | 55,840 psi | 90% | 3038 fps | 100% |
| Accurate 2520 | <<locked>> | 82% | 54,186 psi | 87% | 3058 fps | 100% |
| Accurate 2700 | <<locked>> | 88% | 55,274 psi | 89% | 3045 fps | 96.9% |
| Accurate 3100ᴾ | <<locked>> | 100% | 43,337 psi | 69% | 2917 fps | 96% |
| Accurate 4064 | <<locked>> | 90% | 55,912 psi | 90% | 3091 fps | 100% |
| Accurate 4350 | <<locked>> | 96% | 52,750 psi | 85% | 3120 fps | 99.3% |
| ADI AR 2206H | <<locked>> | 86% | 56,347 psi | 90% | 3127 fps | 100% |
| ADI AR 2208 | <<locked>> | 90% | 54,128 psi | 87% | 3071 fps | 99.7% |
| ADI Benchmark 8208 | <<locked>> | 84% | 55,361 psi | 89% | 3077 fps | 100% |
| Alliant AR-Comp | <<locked>> | 82% | 52,852 psi | 85% | 2999 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 86% | 52,736 psi | 85% | 3189 fps | 99.6% |
| Alliant Reloder- TS 15.5 | <<locked>> | 90% | 54,302 psi | 87% | 3097 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 88% | 54,752 psi | 88% | 3117 fps | 99.8% |
| Alliant Reloder-16 | <<locked>> | 98% | 54,157 psi | 87% | 3189 fps | 99.7% |
| Alliant Reloder-17 | <<locked>> | 94% | 55,521 psi | 89% | 3225 fps | 100% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 41,394 psi | 66% | 2953 fps | 98.9% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 46,775 psi | 75% | 3133 fps | 98.4% |
| Baschieri & Pellagri 107 | <<locked>> | 84% | 52,765 psi | 85% | 3081 fps | 99.4% |
| Bofors RP3 | <<locked>> | 90% | 54,897 psi | 88% | 3110 fps | 100% |
| Bofors RP7 | <<locked>> | 94% | 54,882 psi | 88% | 3081 fps | 97.1% |
| Hodgdon Benchmark | <<locked>> | 82% | 53,476 psi | 86% | 3005 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 84% | 54,998 psi | 88% | 3104 fps | 100% |
| Hodgdon H380 | <<locked>> | 90% | 55,883 psi | 90% | 3127 fps | 99.3% |
| Hodgdon H414 | <<locked>> | 96% | 56,028 psi | 90% | 3182 fps | 97.9% |
| Hodgdon H4350 | <<locked>> | 94% | 56,260 psi | 90% | 3140 fps | 96.7% |
| Hodgdon H4895 | <<locked>> | 84% | 53,519 psi | 86% | 3081 fps | 100% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 54,172 psi | 87% | 3110 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 86% | 53,142 psi | 85% | 3114 fps | 100% |
| Hodgdon Superformance | <<locked>> | 94% | 52,620 psi | 84% | 3150 fps | 96.9% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 35,404 psi | 57% | 1932 fps | 100% |
| Hodgdon VARGET | <<locked>> | 86% | 54,737 psi | 88% | 3084 fps | 100% |
| IMR 3031 | <<locked>> | 84% | 53,519 psi | 86% | 3068 fps | 100% |
| IMR 4064 | <<locked>> | 88% | 53,519 psi | 86% | 3054 fps | 99.7% |
| IMR 4166 Enduron | <<locked>> | 86% | 53,490 psi | 86% | 3031 fps | 97.3% |
| IMR 4350 | <<locked>> | 98% | 55,535 psi | 89% | 3107 fps | 97.2% |
| IMR 4451 Enduron | <<locked>> | 92% | 53,432 psi | 86% | 3058 fps | 97.2% |
| IMR 4831 | <<locked>> | 98% | 53,476 psi | 86% | 3114 fps | 99.4% |
| IMR 4895 | <<locked>> | 88% | 56,188 psi | 90% | 3153 fps | 100% |
| IMR 8208 XBR | <<locked>> | 84% | 55,361 psi | 89% | 3077 fps | 100% |
| Lovex D073.6 | <<locked>> | 84% | 52,794 psi | 85% | 3045 fps | 100% |
| Lovex S060 | <<locked>> | 86% | 55,695 psi | 89% | 3051 fps | 99.9% |
| Lovex S062 | <<locked>> | 88% | 53,490 psi | 86% | 3051 fps | 100% |
| Lovex S065 | <<locked>> | 96% | 56,217 psi | 90% | 3107 fps | 98.9% |
| Lovex S070 | <<locked>> | 96% | 53,911 psi | 86% | 3087 fps | 97.7% |
| Norma 201 | <<locked>> | 86% | 54,984 psi | 88% | 3068 fps | 100% |
| Norma 202 | <<locked>> | 86% | 55,637 psi | 89% | 3068 fps | 100% |
| Norma 203B | <<locked>> | 88% | 53,954 psi | 87% | 3104 fps | 99.9% |
| Norma 204 | <<locked>> | 98% | 56,347 psi | 90% | 3163 fps | 96.1% |
| Norma URP | <<locked>> | 98% | 55,637 psi | 89% | 3169 fps | 99.5% |
| Ramshot Big Game | <<locked>> | 88% | 54,824 psi | 88% | 3130 fps | 99.9% |
| Ramshot Hunter | <<locked>> | 98% | 54,534 psi | 87% | 3163 fps | 98.4% |
| Ramshot TAC | <<locked>> | 84% | 55,782 psi | 89% | 3094 fps | 98.9% |
| Ramshot Wild Boar | <<locked>> | 84% | 55,521 psi | 89% | 3114 fps | 99.9% |
| Ramshot X-Terminator | <<locked>> | 82% | 56,275 psi | 90% | 3077 fps | 99.9% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 35,911 psi | 58% | 1978 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 90% | 56,130 psi | 90% | 3107 fps | 98.3% |
| ReloadSwiss RS 52 | <<locked>> | 86% | 55,448 psi | 89% | 3189 fps | 99.8% |
| ReloadSwiss RS 60 | <<locked>> | 92% | 55,245 psi | 89% | 3228 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 96% | 52,881 psi | 85% | 3146 fps | 99.2% |
| ReloadSwiss RS 70 | <<locked>> | 98% | 55,985 psi | 90% | 3238 fps | 99.4% |
| Rottweil R 901 | <<locked>> | 84% | 55,564 psi | 89% | 3048 fps | 100% |
| Rottweil R 902 | <<locked>> | 88% | 55,506 psi | 89% | 3064 fps | 100% |
| Rottweil R 903 | <<locked>> | 92% | 54,766 psi | 88% | 3100 fps | 100% |
| Rottweil R 907 | <<locked>> | 94% | 54,882 psi | 88% | 3081 fps | 97.1% |
| Shooters World Long Rifle | <<locked>> | 96% | 56,217 psi | 90% | 3107 fps | 98.9% |
| Shooters World Match Rifle | <<locked>> | 84% | 52,794 psi | 85% | 3045 fps | 100% |
| Shooters World Precision | <<locked>> | 88% | 53,490 psi | 86% | 3051 fps | 100% |
| Shooters World SW4350 | <<locked>> | 96% | 53,911 psi | 86% | 3087 fps | 97.7% |
| SNPE Vectan SP 11 | <<locked>> | 90% | 53,142 psi | 85% | 3110 fps | 99.8% |
| SNPE Vectan SP 7 | <<locked>> | 84% | 54,012 psi | 87% | 3064 fps | 99% |
| SNPE Vectan SP 9 | <<locked>> | 86% | 54,998 psi | 88% | 3097 fps | 99.9% |
| SNPE Vectan Tubal 3000 | <<locked>> | 86% | 56,376 psi | 90% | 3005 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 90% | 53,563 psi | 86% | 2956 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 94% | 52,924 psi | 85% | 2999 fps | 97.2% |
| Somchem S335 | <<locked>> | 86% | 55,869 psi | 90% | 3002 fps | 100% |
| Somchem S341 | <<locked>> | 84% | 53,766 psi | 86% | 3058 fps | 99.8% |
| Somchem S355 | <<locked>> | 92% | 55,129 psi | 88% | 3104 fps | 100% |
| Somchem S365ᴾ | <<locked>> | 100% | 53,809 psi | 86% | 3169 fps | 100% |
| Somchem S385ᴾ | <<locked>> | 100% | 49,719 psi | 80% | 3035 fps | 95.9% |
| Vihtavuori N130 | <<locked>> | 82% | 56,057 psi | 90% | 2966 fps | 100% |
| Vihtavuori N133 | <<locked>> | 84% | 53,519 psi | 86% | 2943 fps | 100% |
| Vihtavuori N135 | <<locked>> | 88% | 55,434 psi | 89% | 3031 fps | 100% |
| Vihtavuori N140 | <<locked>> | 88% | 56,376 psi | 90% | 3048 fps | 100% |
| Vihtavuori N150 | <<locked>> | 92% | 53,084 psi | 85% | 3025 fps | 100% |
| Vihtavuori N160 | <<locked>> | 96% | 54,476 psi | 87% | 3110 fps | 99.4% |
| Vihtavuori N530 | <<locked>> | 84% | 55,970 psi | 90% | 3077 fps | 100% |
| Vihtavuori N540 | <<locked>> | 88% | 54,563 psi | 87% | 3041 fps | 100% |
| Vihtavuori N550 | <<locked>> | 96% | 53,693 psi | 86% | 3114 fps | 99.2% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 45,658 psi | 73% | 3035 fps | 98.8% |
| Winchester 6.5 StaBALL | <<locked>> | 96% | 54,984 psi | 88% | 3087 fps | 100% |
| Winchester 748 | <<locked>> | 84% | 56,246 psi | 90% | 3130 fps | 100% |
| Winchester 760 | <<locked>> | 96% | 56,028 psi | 90% | 3182 fps | 97.9% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 36,970 psi | 59% | 2949 fps | 98.8% |
| Winchester StaBALL Match | <<locked>> | 86% | 55,100 psi | 88% | 3107 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% | 50,169 psi | 80% | 2917 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 42,627 psi | 68% | 2825 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 50,357 psi | 81% | 2999 fps | 100% |
| Accurate 2700 | <<locked>> | 84% | 48,385 psi | 78% | 2923 fps | 95.3% |
| Accurate 3100 | <<locked>> | 98% | 40,451 psi | 65% | 2854 fps | 95.2% |
| Accurate 4064 | <<locked>> | 80% | 40,335 psi | 65% | 2818 fps | 100% |
| Accurate 4350 | <<locked>> | 86% | 36,840 psi | 59% | 2799 fps | 95.8% |
| ADI AR 2206H | <<locked>> | 80% | 46,586 psi | 75% | 2953 fps | 99.2% |
| ADI AR 2208 | <<locked>> | 80% | 39,552 psi | 63% | 2785 fps | 97.3% |
| ADI Benchmark 8208 | <<locked>> | 80% | 48,704 psi | 78% | 2963 fps | 99.9% |
| Alliant AR-Comp | <<locked>> | 80% | 49,414 psi | 79% | 2949 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 42,699 psi | 68% | 2989 fps | 98% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 39,175 psi | 63% | 2808 fps | 98.6% |
| Alliant Reloder-15 | <<locked>> | 80% | 42,163 psi | 68% | 2881 fps | 98.1% |
| Alliant Reloder-16 | <<locked>> | 84% | 34,548 psi | 55% | 2759 fps | 95% |
| Alliant Reloder-17 | 61.1 gr | 80% | 33,895 psi | 54% | 2766 fps | 96.7% |
| Alliant Reloder-23 | <<locked>> | 92% | 31,923 psi | 51% | 2707 fps | 95.7% |
| Alliant Reloder-26 | <<locked>> | 94% | 37,463 psi | 60% | 2910 fps | 95.4% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 46,006 psi | 74% | 2956 fps | 98.4% |
| Bofors RP3 | <<locked>> | 80% | 38,870 psi | 62% | 2808 fps | 98.6% |
| Bofors RP7 | <<locked>> | 90% | 48,225 psi | 77% | 2959 fps | 95.6% |
| Hodgdon Benchmark | <<locked>> | 80% | 50,270 psi | 81% | 2949 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 80% | 47,877 psi | 77% | 2982 fps | 100% |
| Hodgdon H380 | <<locked>> | 80% | 39,653 psi | 64% | 2815 fps | 96.2% |
| Hodgdon H414 | <<locked>> | 90% | 45,600 psi | 73% | 2989 fps | 95.6% |
| Hodgdon H4350 | <<locked>> | 90% | 49,458 psi | 79% | 3018 fps | 95.1% |
| Hodgdon H4895 | <<locked>> | 80% | 47,036 psi | 75% | 2966 fps | 99.5% |
| Hodgdon Hybrid 100V | <<locked>> | 84% | 31,691 psi | 51% | 2644 fps | 95.8% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 43,279 psi | 69% | 2933 fps | 99.4% |
| Hodgdon Superformance | 72.7 gr | 90% | 45,484 psi | 73% | 3009 fps | 95% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,295 psi | 42% | 1729 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 45,136 psi | 72% | 2913 fps | 99.3% |
| IMR 3031 | <<locked>> | 80% | 46,862 psi | 75% | 2959 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 41,539 psi | 67% | 2825 fps | 98% |
| IMR 4166 Enduron | <<locked>> | 80% | 43,888 psi | 70% | 2848 fps | 95% |
| IMR 4350 | <<locked>> | 92% | 45,919 psi | 74% | 2933 fps | 95% |
| IMR 4451 Enduron | <<locked>> | 86% | 44,280 psi | 71% | 2881 fps | 95% |
| IMR 4831 | <<locked>> | 86% | 35,665 psi | 57% | 2753 fps | 95.5% |
| IMR 4895 | <<locked>> | 80% | 43,236 psi | 69% | 2913 fps | 98.8% |
| IMR 8208 XBR | <<locked>> | 80% | 48,704 psi | 78% | 2963 fps | 99.9% |
| Lovex D073.6 | <<locked>> | 80% | 45,977 psi | 74% | 2930 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 46,354 psi | 74% | 2887 fps | 99.2% |
| Lovex S062 | <<locked>> | 80% | 41,350 psi | 66% | 2828 fps | 99.3% |
| Lovex S065 | <<locked>> | 86% | 41,089 psi | 66% | 2818 fps | 95.7% |
| Lovex S070 | <<locked>> | 90% | 44,295 psi | 71% | 2904 fps | 95.4% |
| Norma 201 | <<locked>> | 80% | 45,324 psi | 73% | 2900 fps | 99.7% |
| Norma 202 | <<locked>> | 80% | 45,832 psi | 73% | 2907 fps | 100% |
| Norma 203B | <<locked>> | 80% | 41,553 psi | 67% | 2867 fps | 98.4% |
| Norma 204 | <<locked>> | 96% | 52,576 psi | 84% | 3097 fps | 95.2% |
| Norma URP | <<locked>> | 86% | 37,260 psi | 60% | 2805 fps | 95.8% |
| Ramshot Big Game | <<locked>> | 80% | 41,379 psi | 66% | 2881 fps | 98.2% |
| Ramshot Hunter | <<locked>> | 90% | 41,582 psi | 67% | 2910 fps | 95.3% |
| Ramshot TAC | <<locked>> | 80% | 48,617 psi | 78% | 2966 fps | 97.8% |
| Ramshot Wild Boar | <<locked>> | 80% | 48,443 psi | 78% | 2992 fps | 99.4% |
| Ramshot X-Terminator | <<locked>> | 80% | 52,576 psi | 84% | 3015 fps | 99.7% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 26,658 psi | 43% | 1768 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 82% | 42,917 psi | 69% | 2858 fps | 95.4% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 44,846 psi | 72% | 2995 fps | 98.5% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 36,129 psi | 58% | 2844 fps | 99.4% |
| ReloadSwiss RS 62 | <<locked>> | 86% | 36,767 psi | 59% | 2818 fps | 95.4% |
| ReloadSwiss RS 70 | 68.3 gr | 88% | 39,436 psi | 63% | 2897 fps | 95.6% |
| Rottweil R 901 | <<locked>> | 80% | 49,284 psi | 79% | 2943 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 43,149 psi | 69% | 2844 fps | 99.5% |
| Rottweil R 903 | <<locked>> | 80% | 36,463 psi | 58% | 2746 fps | 97.8% |
| Rottweil R 907 | <<locked>> | 90% | 48,225 psi | 77% | 2959 fps | 95.6% |
| Shooters World Long Rifle | <<locked>> | 86% | 41,089 psi | 66% | 2818 fps | 95.7% |
| Shooters World Match Rifle | <<locked>> | 80% | 45,977 psi | 74% | 2930 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 41,350 psi | 66% | 2828 fps | 99.3% |
| Shooters World SW4350 | <<locked>> | 90% | 44,295 psi | 71% | 2904 fps | 95.4% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 37,811 psi | 61% | 2805 fps | 97.4% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 46,978 psi | 75% | 2940 fps | 97.9% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 45,150 psi | 72% | 2920 fps | 99% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 46,688 psi | 75% | 2851 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 38,943 psi | 62% | 2703 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 90% | 46,354 psi | 74% | 2877 fps | 95.8% |
| Somchem S335 | <<locked>> | 80% | 46,296 psi | 74% | 2848 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 46,833 psi | 75% | 2936 fps | 99.2% |
| Somchem S355 | <<locked>> | 80% | 37,304 psi | 60% | 2756 fps | 97.8% |
| Somchem S365 | <<locked>> | 80% | 27,093 psi | 43% | 2559 fps | 95% |
| Somchem S385 | <<locked>> | 98% | 46,601 psi | 75% | 2979 fps | 95.1% |
| Vihtavuori N130 | <<locked>> | 80% | 52,678 psi | 84% | 2917 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 47,137 psi | 76% | 2844 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 42,830 psi | 69% | 2828 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 43,395 psi | 70% | 2835 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 35,476 psi | 57% | 2687 fps | 98.5% |
| Vihtavuori N160 | <<locked>> | 84% | 36,347 psi | 58% | 2749 fps | 95.5% |
| Vihtavuori N530 | <<locked>> | 80% | 48,834 psi | 78% | 2959 fps | 99.9% |
| Vihtavuori N540 | <<locked>> | 80% | 41,843 psi | 67% | 2822 fps | 100% |
| Vihtavuori N550 | <<locked>> | 84% | 35,708 psi | 57% | 2746 fps | 95% |
| Vihtavuori N555 | <<locked>> | 92% | 34,679 psi | 56% | 2789 fps | 95.8% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 31,502 psi | 51% | 2602 fps | 96% |
| Winchester 748 | <<locked>> | 80% | 48,892 psi | 78% | 3009 fps | 100% |
| Winchester 760 | <<locked>> | 90% | 45,600 psi | 73% | 2989 fps | 95.6% |
| Winchester StaBALL HD | <<locked>> | 94% | 30,153 psi | 48% | 2726 fps | 95.2% |
| Winchester StaBALL Match | <<locked>> | 80% | 44,614 psi | 72% | 2920 fps | 99.3% |
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 95 powders for .300 Win. Mag. loaded with the .308 | 146gr | Peregrine Glider (Glider GRM). ReloadSwiss RS 70 delivers the highest muzzle velocity at 3,238 fps; across all powders the maximum-charge window runs from 1,932 fps to 3,238 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 146.0 gr projectile in 0.308" calls for a 1:11.0 twist; slower twists will usually not stabilise this weight. Accurate 3100, Alliant Reloder-23, Alliant Reloder-26 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, Hodgdon Superformance, Alliant Reloder-17 rank at the top here: for .300 Win. Mag. with the .308 | 146gr | Peregrine Glider (Glider GRM) 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.