Load Specifications
Load data in caliber .300 H&H Mag. with .308 | 155.8gr | 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 Alliant Reloder-17, ReloadSwiss RS 60 and Hodgdon H414.
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>> | 84% | 56,101 psi | 90% | 2881 fps | 100% |
| Accurate 2495 | <<locked>> | 88% | 54,636 psi | 88% | 2900 fps | 100% |
| Accurate 2520 | <<locked>> | 82% | 52,924 psi | 85% | 2917 fps | 100% |
| Accurate 2700 | <<locked>> | 88% | 54,244 psi | 87% | 2904 fps | 96.8% |
| Accurate 4064 | <<locked>> | 90% | 54,752 psi | 88% | 2946 fps | 100% |
| Accurate 4350 | <<locked>> | 98% | 55,259 psi | 89% | 3038 fps | 99.6% |
| ADI AR 2206H | <<locked>> | 86% | 55,347 psi | 89% | 2982 fps | 99.9% |
| ADI AR 2208 | <<locked>> | 90% | 53,069 psi | 85% | 2930 fps | 99.6% |
| ADI Benchmark 8208 | <<locked>> | 84% | 54,447 psi | 87% | 2933 fps | 100% |
| Alliant AR-Comp | <<locked>> | 84% | 55,317 psi | 89% | 2907 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 88% | 55,492 psi | 89% | 3110 fps | 99.9% |
| Alliant Reloder- TS 15.5 | <<locked>> | 90% | 53,040 psi | 85% | 2953 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 88% | 53,664 psi | 86% | 2976 fps | 99.7% |
| Alliant Reloder-16ᴾ | <<locked>> | 100% | 56,260 psi | 90% | 3097 fps | 99.9% |
| Alliant Reloder-17 | <<locked>> | 94% | 54,172 psi | 87% | 3081 fps | 100% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 40,118 psi | 64% | 2812 fps | 98.8% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 45,266 psi | 73% | 2986 fps | 98.2% |
| Baschieri & Pellagri 107 | <<locked>> | 86% | 55,521 psi | 89% | 3002 fps | 99.7% |
| Bofors RP3 | <<locked>> | 90% | 53,577 psi | 86% | 2966 fps | 100% |
| Bofors RP7 | <<locked>> | 94% | 53,838 psi | 86% | 2940 fps | 96.9% |
| Hodgdon Benchmark | <<locked>> | 84% | 55,999 psi | 90% | 2917 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 84% | 53,809 psi | 86% | 2963 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 82% | 55,854 psi | 90% | 3064 fps | 99.9% |
| Hodgdon H380 | <<locked>> | 90% | 54,679 psi | 88% | 2982 fps | 99.2% |
| Hodgdon H414 | <<locked>> | 96% | 54,462 psi | 87% | 3035 fps | 97.7% |
| Hodgdon H4350 | <<locked>> | 94% | 54,955 psi | 88% | 2995 fps | 96.5% |
| Hodgdon H4895 | <<locked>> | 86% | 55,912 psi | 90% | 2995 fps | 100% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 52,663 psi | 84% | 2966 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 88% | 55,622 psi | 89% | 3028 fps | 100% |
| Hodgdon Superformance | <<locked>> | 96% | 55,245 psi | 89% | 3074 fps | 97.5% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 35,549 psi | 57% | 1837 fps | 100% |
| Hodgdon VARGET | <<locked>> | 86% | 53,679 psi | 86% | 2943 fps | 100% |
| IMR 3031 | <<locked>> | 86% | 56,188 psi | 90% | 2979 fps | 100% |
| IMR 4064 | <<locked>> | 90% | 55,883 psi | 90% | 2966 fps | 99.9% |
| IMR 4166 Enduron | <<locked>> | 88% | 55,985 psi | 90% | 2949 fps | 97.8% |
| IMR 4350 | <<locked>> | 98% | 54,259 psi | 87% | 2966 fps | 97.1% |
| IMR 4451 Enduron | <<locked>> | 94% | 55,825 psi | 90% | 2972 fps | 97.7% |
| IMR 4831ᴾ | <<locked>> | 100% | 55,796 psi | 89% | 3028 fps | 99.7% |
| IMR 4895 | <<locked>> | 88% | 55,056 psi | 88% | 3005 fps | 100% |
| IMR 8208 XBR | <<locked>> | 84% | 54,447 psi | 87% | 2933 fps | 100% |
| Lovex D073.6 | <<locked>> | 86% | 55,172 psi | 88% | 2959 fps | 100% |
| Lovex S060 | <<locked>> | 86% | 54,781 psi | 88% | 2910 fps | 99.9% |
| Lovex S062 | <<locked>> | 90% | 55,767 psi | 89% | 2963 fps | 100% |
| Lovex S065 | <<locked>> | 96% | 55,071 psi | 88% | 2963 fps | 98.8% |
| Lovex S070 | <<locked>> | 98% | 55,970 psi | 90% | 2999 fps | 98.1% |
| Norma 201 | <<locked>> | 86% | 54,070 psi | 87% | 2930 fps | 100% |
| Norma 202 | <<locked>> | 86% | 54,723 psi | 88% | 2930 fps | 100% |
| Norma 203B | <<locked>> | 90% | 56,231 psi | 90% | 3012 fps | 100% |
| Norma 204 | <<locked>> | 98% | 54,853 psi | 88% | 3012 fps | 95.9% |
| Norma URP | <<locked>> | 98% | 54,114 psi | 87% | 3022 fps | 99.5% |
| Ramshot Big Game | <<locked>> | 88% | 53,534 psi | 86% | 2986 fps | 99.8% |
| Ramshot Hunter | <<locked>> | 98% | 53,011 psi | 85% | 3018 fps | 98.3% |
| Ramshot TAC | <<locked>> | 84% | 54,592 psi | 88% | 2949 fps | 98.8% |
| Ramshot Wild Boar | <<locked>> | 84% | 54,404 psi | 87% | 2972 fps | 99.9% |
| Ramshot X-Terminator | <<locked>> | 82% | 55,274 psi | 89% | 2936 fps | 99.9% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 35,911 psi | 58% | 1880 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 90% | 54,940 psi | 88% | 2963 fps | 98.2% |
| ReloadSwiss RS 52 | <<locked>> | 86% | 54,056 psi | 87% | 3041 fps | 99.7% |
| ReloadSwiss RS 60 | <<locked>> | 92% | 53,679 psi | 86% | 3077 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 98% | 54,926 psi | 88% | 3058 fps | 99.4% |
| ReloadSwiss RS 70 | <<locked>> | 98% | 54,578 psi | 88% | 3091 fps | 99.3% |
| Rottweil R 901 | <<locked>> | 84% | 54,650 psi | 88% | 2907 fps | 100% |
| Rottweil R 902 | <<locked>> | 88% | 54,360 psi | 87% | 2923 fps | 100% |
| Rottweil R 903 | <<locked>> | 92% | 53,447 psi | 86% | 2959 fps | 100% |
| Rottweil R 907 | <<locked>> | 94% | 53,838 psi | 86% | 2940 fps | 96.9% |
| Shooters World Long Rifle | <<locked>> | 96% | 55,071 psi | 88% | 2963 fps | 98.8% |
| Shooters World Match Rifle | <<locked>> | 86% | 55,172 psi | 88% | 2959 fps | 100% |
| Shooters World Precision | <<locked>> | 90% | 55,767 psi | 89% | 2963 fps | 100% |
| Shooters World SW4350 | <<locked>> | 98% | 55,970 psi | 90% | 2999 fps | 98.1% |
| SNPE Vectan SP 11 | <<locked>> | 92% | 55,434 psi | 89% | 3022 fps | 99.9% |
| SNPE Vectan SP 7 | <<locked>> | 84% | 52,939 psi | 85% | 2927 fps | 99% |
| SNPE Vectan SP 9 | <<locked>> | 86% | 53,809 psi | 86% | 2953 fps | 99.9% |
| SNPE Vectan Tubal 3000 | <<locked>> | 86% | 55,666 psi | 89% | 2867 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 92% | 55,956 psi | 90% | 2864 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 96% | 55,245 psi | 89% | 2913 fps | 97.7% |
| Somchem S321 | <<locked>> | 82% | 55,477 psi | 89% | 2966 fps | 100% |
| Somchem S335 | <<locked>> | 86% | 54,969 psi | 88% | 2864 fps | 100% |
| Somchem S341 | <<locked>> | 84% | 52,721 psi | 85% | 2920 fps | 99.8% |
| Somchem S355 | <<locked>> | 92% | 53,766 psi | 86% | 2956 fps | 100% |
| Somchem S365ᴾ | <<locked>> | 100% | 52,170 psi | 84% | 3025 fps | 100% |
| Vihtavuori N130 | <<locked>> | 82% | 55,187 psi | 88% | 2828 fps | 100% |
| Vihtavuori N133 | <<locked>> | 86% | 55,985 psi | 90% | 2854 fps | 100% |
| Vihtavuori N135 | <<locked>> | 88% | 54,288 psi | 87% | 2890 fps | 100% |
| Vihtavuori N140 | <<locked>> | 88% | 55,172 psi | 88% | 2907 fps | 100% |
| Vihtavuori N150 | <<locked>> | 94% | 55,506 psi | 89% | 2940 fps | 100% |
| Vihtavuori N160 | <<locked>> | 96% | 53,156 psi | 85% | 2966 fps | 99.3% |
| Vihtavuori N530 | <<locked>> | 84% | 54,882 psi | 88% | 2933 fps | 100% |
| Vihtavuori N540 | <<locked>> | 88% | 53,476 psi | 86% | 2904 fps | 100% |
| Vihtavuori N550 | <<locked>> | 98% | 55,782 psi | 89% | 3025 fps | 99.5% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 44,280 psi | 71% | 2894 fps | 98.7% |
| Winchester 6.5 StaBALL | <<locked>> | 96% | 53,577 psi | 86% | 2946 fps | 100% |
| Winchester 748 | <<locked>> | 84% | 54,868 psi | 88% | 2982 fps | 100% |
| Winchester 760 | <<locked>> | 96% | 54,737 psi | 88% | 3038 fps | 97.8% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 35,868 psi | 58% | 2808 fps | 98.6% |
| Winchester StaBALL Match | <<locked>> | 86% | 53,780 psi | 86% | 2963 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% | 49,400 psi | 79% | 2782 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 41,785 psi | 67% | 2697 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 49,385 psi | 79% | 2861 fps | 100% |
| Accurate 2700 | <<locked>> | 84% | 47,253 psi | 76% | 2782 fps | 95.2% |
| Accurate 4064 | <<locked>> | 80% | 39,552 psi | 63% | 2690 fps | 100% |
| Accurate 4350 | <<locked>> | 86% | 35,911 psi | 58% | 2671 fps | 95.7% |
| ADI AR 2206H | <<locked>> | 80% | 45,759 psi | 73% | 2818 fps | 99.2% |
| ADI AR 2208 | <<locked>> | 80% | 38,856 psi | 62% | 2657 fps | 97.3% |
| ADI Benchmark 8208 | <<locked>> | 80% | 47,921 psi | 77% | 2828 fps | 99.9% |
| Alliant AR-Comp | <<locked>> | 80% | 48,399 psi | 78% | 2812 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 41,756 psi | 67% | 2848 fps | 97.9% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 38,479 psi | 62% | 2680 fps | 98.6% |
| Alliant Reloder-15 | <<locked>> | 80% | 41,379 psi | 66% | 2749 fps | 98% |
| Alliant Reloder-16 | <<locked>> | 86% | 36,071 psi | 58% | 2687 fps | 95.9% |
| Alliant Reloder-17 | 56.9 gr | 80% | 33,185 psi | 53% | 2638 fps | 96.6% |
| Alliant Reloder-23 | <<locked>> | 92% | 31,038 psi | 50% | 2575 fps | 95.5% |
| Alliant Reloder-26 | <<locked>> | 94% | 36,289 psi | 58% | 2772 fps | 95.1% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 45,136 psi | 72% | 2822 fps | 98.4% |
| Bofors RP3 | <<locked>> | 80% | 37,927 psi | 61% | 2677 fps | 98.6% |
| Bofors RP7 | <<locked>> | 90% | 47,340 psi | 76% | 2822 fps | 95.5% |
| Hodgdon Benchmark | <<locked>> | 80% | 49,414 psi | 79% | 2815 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 80% | 46,818 psi | 75% | 2848 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 80% | 51,953 psi | 83% | 3002 fps | 99.6% |
| Hodgdon H380 | <<locked>> | 80% | 38,841 psi | 62% | 2684 fps | 96.1% |
| Hodgdon H414 | 62.6 gr | 90% | 44,367 psi | 71% | 2851 fps | 95.4% |
| Hodgdon H4350 | <<locked>> | 92% | 51,663 psi | 83% | 2940 fps | 95.8% |
| Hodgdon H4895 | <<locked>> | 80% | 46,195 psi | 74% | 2831 fps | 99.5% |
| Hodgdon Hybrid 100V | <<locked>> | 84% | 30,966 psi | 50% | 2520 fps | 95.7% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 42,337 psi | 68% | 2799 fps | 99.3% |
| Hodgdon Superformance | <<locked>> | 92% | 47,674 psi | 76% | 2936 fps | 95.7% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,368 psi | 42% | 1640 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 44,338 psi | 71% | 2779 fps | 99.3% |
| IMR 3031 | <<locked>> | 80% | 45,876 psi | 74% | 2822 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 40,814 psi | 65% | 2697 fps | 98% |
| IMR 4166 Enduron | <<locked>> | 82% | 46,238 psi | 74% | 2776 fps | 95.8% |
| IMR 4350 | <<locked>> | 94% | 47,747 psi | 77% | 2851 fps | 95.6% |
| IMR 4451 Enduron | <<locked>> | 88% | 46,354 psi | 74% | 2805 fps | 95.7% |
| IMR 4831 | <<locked>> | 86% | 34,766 psi | 56% | 2625 fps | 95.4% |
| IMR 4895 | <<locked>> | 80% | 42,409 psi | 68% | 2779 fps | 98.7% |
| IMR 8208 XBR | <<locked>> | 80% | 47,921 psi | 77% | 2828 fps | 99.9% |
| Lovex D073.6 | <<locked>> | 80% | 44,875 psi | 72% | 2792 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 45,629 psi | 73% | 2753 fps | 99.2% |
| Lovex S062 | <<locked>> | 80% | 40,596 psi | 65% | 2697 fps | 99.2% |
| Lovex S065 | <<locked>> | 86% | 40,306 psi | 65% | 2690 fps | 95.6% |
| Lovex S070 | <<locked>> | 90% | 43,468 psi | 70% | 2772 fps | 95.3% |
| Norma 201 | <<locked>> | 80% | 44,599 psi | 72% | 2766 fps | 99.7% |
| Norma 202 | <<locked>> | 80% | 45,121 psi | 72% | 2776 fps | 100% |
| Norma 203B | <<locked>> | 80% | 40,756 psi | 65% | 2736 fps | 98.4% |
| Norma 204 | <<locked>> | 96% | 51,198 psi | 82% | 2949 fps | 95% |
| Norma URP | <<locked>> | 86% | 36,303 psi | 58% | 2674 fps | 95.7% |
| Ramshot Big Game | <<locked>> | 80% | 40,437 psi | 65% | 2746 fps | 98.1% |
| Ramshot Hunter | <<locked>> | 90% | 40,480 psi | 65% | 2776 fps | 95.1% |
| Ramshot TAC | <<locked>> | 80% | 47,776 psi | 77% | 2831 fps | 97.7% |
| Ramshot Wild Boar | <<locked>> | 80% | 47,471 psi | 76% | 2854 fps | 99.4% |
| Ramshot X-Terminator | <<locked>> | 80% | 51,605 psi | 83% | 2877 fps | 99.7% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 26,585 psi | 43% | 1677 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 82% | 42,018 psi | 67% | 2726 fps | 95.3% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 43,743 psi | 70% | 2854 fps | 98.5% |
| ReloadSwiss RS 60 | 56.9 gr | 80% | 35,360 psi | 57% | 2710 fps | 99.4% |
| ReloadSwiss RS 62 | <<locked>> | 86% | 35,824 psi | 57% | 2690 fps | 95.3% |
| ReloadSwiss RS 70 | <<locked>> | 88% | 38,508 psi | 62% | 2762 fps | 95.4% |
| Rottweil R 901 | <<locked>> | 80% | 48,283 psi | 77% | 2805 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 42,322 psi | 68% | 2713 fps | 99.4% |
| Rottweil R 903 | <<locked>> | 80% | 35,766 psi | 57% | 2621 fps | 97.8% |
| Rottweil R 907 | <<locked>> | 90% | 47,340 psi | 76% | 2822 fps | 95.5% |
| Shooters World Long Rifle | <<locked>> | 86% | 40,306 psi | 65% | 2690 fps | 95.6% |
| Shooters World Match Rifle | <<locked>> | 80% | 44,875 psi | 72% | 2792 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 40,596 psi | 65% | 2697 fps | 99.2% |
| Shooters World SW4350 | <<locked>> | 90% | 43,468 psi | 70% | 2772 fps | 95.3% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 36,869 psi | 59% | 2674 fps | 97.3% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 46,035 psi | 74% | 2805 fps | 97.9% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 44,179 psi | 71% | 2782 fps | 99% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 45,963 psi | 74% | 2720 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 38,276 psi | 61% | 2575 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 90% | 45,440 psi | 73% | 2746 fps | 95.6% |
| Somchem S321 | <<locked>> | 80% | 51,909 psi | 83% | 2910 fps | 100% |
| Somchem S335 | <<locked>> | 80% | 45,585 psi | 73% | 2720 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 45,948 psi | 74% | 2805 fps | 99.2% |
| Somchem S355 | <<locked>> | 80% | 36,622 psi | 59% | 2628 fps | 97.8% |
| Somchem S365 | <<locked>> | 80% | 26,498 psi | 42% | 2441 fps | 95% |
| Vihtavuori N130 | <<locked>> | 80% | 51,895 psi | 83% | 2782 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 46,383 psi | 74% | 2710 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 42,003 psi | 67% | 2697 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 42,728 psi | 69% | 2707 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 34,882 psi | 56% | 2566 fps | 98.5% |
| Vihtavuori N160 | <<locked>> | 84% | 35,534 psi | 57% | 2625 fps | 95.4% |
| Vihtavuori N530 | <<locked>> | 80% | 47,863 psi | 77% | 2822 fps | 99.9% |
| Vihtavuori N540 | <<locked>> | 80% | 41,031 psi | 66% | 2690 fps | 100% |
| Vihtavuori N550 | <<locked>> | 86% | 37,362 psi | 60% | 2680 fps | 95.8% |
| Vihtavuori N555 | <<locked>> | 92% | 33,721 psi | 54% | 2661 fps | 95.7% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 30,879 psi | 50% | 2480 fps | 95.9% |
| Winchester 748 | <<locked>> | 80% | 47,906 psi | 77% | 2871 fps | 100% |
| Winchester 760 | <<locked>> | 90% | 44,585 psi | 71% | 2854 fps | 95.5% |
| Winchester StaBALL HD | <<locked>> | 96% | 31,343 psi | 50% | 2667 fps | 96.4% |
| Winchester StaBALL Match | <<locked>> | 80% | 43,758 psi | 70% | 2785 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 H&H Mag. loaded with the .308 | 155.8gr | Peregrine Glider (Glider GRM). Alliant Power Pro 2000-MR delivers the highest muzzle velocity at 3,110 fps; across all powders the maximum-charge window runs from 1,837 fps to 3,110 fps. Alliant Reloder-16 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 156.0 gr projectile in 0.308" calls for a 1:10.5 twist; slower twists will usually not stabilise this weight. Alliant Reloder-16, 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. Alliant Reloder-17, ReloadSwiss RS 60, Hodgdon H414 rank at the top here: for .300 H&H Mag. with the .308 | 155.8gr | 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.