Load Specifications
Load data in caliber .300 H&H Mag. with .308 | 154gr | Hammer HHT 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, ReloadSwiss RS 70 and Hodgdon Superformance.
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% | 56,333 psi | 90% | 2907 fps | 100% |
| Accurate 2495 | <<locked>> | 88% | 55,071 psi | 88% | 2927 fps | 100% |
| Accurate 2520 | <<locked>> | 82% | 53,287 psi | 85% | 2943 fps | 100% |
| Accurate 2700 | <<locked>> | 88% | 54,636 psi | 88% | 2933 fps | 96.8% |
| Accurate 3100ᴾ | <<locked>> | 100% | 42,525 psi | 68% | 2808 fps | 95.9% |
| Accurate 4064 | <<locked>> | 90% | 55,129 psi | 88% | 2976 fps | 100% |
| Accurate 4350 | <<locked>> | 98% | 55,666 psi | 89% | 3068 fps | 99.6% |
| ADI AR 2206H | <<locked>> | 86% | 55,695 psi | 89% | 3012 fps | 99.9% |
| ADI AR 2208 | <<locked>> | 90% | 53,592 psi | 86% | 2963 fps | 99.6% |
| ADI Benchmark 8208 | <<locked>> | 84% | 54,824 psi | 88% | 2966 fps | 100% |
| Alliant AR-Comp | <<locked>> | 84% | 55,869 psi | 90% | 2940 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 88% | 55,956 psi | 90% | 3143 fps | 99.9% |
| Alliant Reloder- TS 15.5 | <<locked>> | 90% | 53,606 psi | 86% | 2982 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 88% | 53,998 psi | 87% | 3005 fps | 99.7% |
| Alliant Reloder-16 | <<locked>> | 98% | 53,258 psi | 85% | 3071 fps | 99.7% |
| Alliant Reloder-17 | <<locked>> | 94% | 54,563 psi | 87% | 3110 fps | 100% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 40,596 psi | 65% | 2844 fps | 98.9% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 45,832 psi | 73% | 3018 fps | 98.3% |
| Baschieri & Pellagri 107 | <<locked>> | 86% | 55,724 psi | 89% | 3028 fps | 99.7% |
| Bofors RP3 | <<locked>> | 90% | 54,085 psi | 87% | 2999 fps | 100% |
| Bofors RP7 | <<locked>> | 94% | 54,302 psi | 87% | 2969 fps | 97% |
| Hodgdon Benchmark | <<locked>> | 84% | 56,434 psi | 90% | 2946 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 84% | 54,099 psi | 87% | 2989 fps | 100% |
| Hodgdon H380 | <<locked>> | 90% | 54,897 psi | 88% | 3009 fps | 99.3% |
| Hodgdon H414 | <<locked>> | 96% | 55,085 psi | 88% | 3064 fps | 97.8% |
| Hodgdon H4350 | <<locked>> | 94% | 55,593 psi | 89% | 3028 fps | 96.6% |
| Hodgdon H4895 | <<locked>> | 86% | 56,260 psi | 90% | 3025 fps | 100% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 53,055 psi | 85% | 2995 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 88% | 56,101 psi | 90% | 3058 fps | 100% |
| Hodgdon Superformance | <<locked>> | 96% | 55,651 psi | 89% | 3104 fps | 97.6% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 35,360 psi | 57% | 1854 fps | 100% |
| Hodgdon VARGET | <<locked>> | 86% | 54,056 psi | 87% | 2972 fps | 100% |
| IMR 3031 | <<locked>> | 86% | 56,420 psi | 90% | 3005 fps | 100% |
| IMR 4064 | <<locked>> | 90% | 56,434 psi | 90% | 2999 fps | 99.9% |
| IMR 4166 Enduron | <<locked>> | 88% | 56,246 psi | 90% | 2976 fps | 97.9% |
| IMR 4350 | <<locked>> | 98% | 54,578 psi | 88% | 2992 fps | 97.1% |
| IMR 4451 Enduron | <<locked>> | 94% | 56,246 psi | 90% | 3002 fps | 97.8% |
| IMR 4831ᴾ | <<locked>> | 100% | 56,130 psi | 90% | 3058 fps | 99.7% |
| IMR 4895 | <<locked>> | 88% | 55,405 psi | 89% | 3035 fps | 100% |
| IMR 8208 XBR | <<locked>> | 84% | 54,824 psi | 88% | 2966 fps | 100% |
| Lovex D073.6 | <<locked>> | 86% | 55,492 psi | 89% | 2986 fps | 100% |
| Lovex S060 | <<locked>> | 86% | 55,172 psi | 88% | 2940 fps | 99.9% |
| Lovex S062 | <<locked>> | 90% | 56,101 psi | 90% | 2992 fps | 100% |
| Lovex S065 | <<locked>> | 96% | 55,492 psi | 89% | 2992 fps | 98.8% |
| Lovex S070 | <<locked>> | 96% | 53,011 psi | 85% | 2972 fps | 97.6% |
| Norma 201 | <<locked>> | 86% | 54,201 psi | 87% | 2953 fps | 100% |
| Norma 202 | <<locked>> | 86% | 55,129 psi | 88% | 2959 fps | 100% |
| Norma 203B | <<locked>> | 88% | 53,185 psi | 85% | 2989 fps | 99.9% |
| Norma 204 | <<locked>> | 98% | 55,390 psi | 89% | 3045 fps | 96% |
| Norma URP | <<locked>> | 98% | 54,766 psi | 88% | 3054 fps | 99.5% |
| Ramshot Big Game | <<locked>> | 88% | 54,027 psi | 87% | 3018 fps | 99.9% |
| Ramshot Hunter | <<locked>> | 98% | 53,548 psi | 86% | 3048 fps | 98.3% |
| Ramshot TAC | <<locked>> | 84% | 55,056 psi | 88% | 2979 fps | 98.9% |
| Ramshot Wild Boar | <<locked>> | 84% | 54,679 psi | 88% | 2999 fps | 99.9% |
| Ramshot X-Terminator | <<locked>> | 82% | 55,564 psi | 89% | 2963 fps | 99.9% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 35,926 psi | 58% | 1900 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 90% | 55,347 psi | 89% | 2992 fps | 98.3% |
| ReloadSwiss RS 52 | <<locked>> | 86% | 54,694 psi | 88% | 3074 fps | 99.8% |
| ReloadSwiss RS 60 | <<locked>> | 92% | 54,375 psi | 87% | 3110 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 98% | 55,477 psi | 89% | 3091 fps | 99.5% |
| ReloadSwiss RS 70 | <<locked>> | 98% | 55,056 psi | 88% | 3120 fps | 99.3% |
| Rottweil R 901 | <<locked>> | 84% | 55,143 psi | 88% | 2936 fps | 100% |
| Rottweil R 902 | <<locked>> | 88% | 54,752 psi | 88% | 2953 fps | 100% |
| Rottweil R 903 | <<locked>> | 92% | 53,954 psi | 87% | 2989 fps | 100% |
| Rottweil R 907 | <<locked>> | 94% | 54,302 psi | 87% | 2969 fps | 97% |
| Shooters World Long Rifle | <<locked>> | 96% | 55,492 psi | 89% | 2992 fps | 98.8% |
| Shooters World Match Rifle | <<locked>> | 86% | 55,492 psi | 89% | 2986 fps | 100% |
| Shooters World Precision | <<locked>> | 90% | 56,101 psi | 90% | 2992 fps | 100% |
| Shooters World SW4350 | <<locked>> | 96% | 53,011 psi | 85% | 2972 fps | 97.6% |
| SNPE Vectan SP 11 | <<locked>> | 92% | 55,840 psi | 90% | 3054 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 84% | 53,432 psi | 86% | 2956 fps | 99% |
| SNPE Vectan SP 9 | <<locked>> | 86% | 54,331 psi | 87% | 2982 fps | 99.9% |
| SNPE Vectan Tubal 3000 | <<locked>> | 86% | 55,840 psi | 90% | 2897 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 92% | 56,260 psi | 90% | 2894 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 96% | 55,854 psi | 90% | 2946 fps | 97.8% |
| Somchem S321 | <<locked>> | 82% | 56,014 psi | 90% | 2995 fps | 100% |
| Somchem S335 | <<locked>> | 86% | 55,100 psi | 88% | 2887 fps | 100% |
| Somchem S341 | <<locked>> | 84% | 53,214 psi | 85% | 2949 fps | 99.8% |
| Somchem S355 | <<locked>> | 92% | 54,273 psi | 87% | 2989 fps | 100% |
| Somchem S365ᴾ | <<locked>> | 100% | 52,779 psi | 85% | 3054 fps | 100% |
| Vihtavuori N130 | <<locked>> | 82% | 55,492 psi | 89% | 2854 fps | 100% |
| Vihtavuori N133 | <<locked>> | 86% | 56,188 psi | 90% | 2881 fps | 100% |
| Vihtavuori N135 | <<locked>> | 88% | 54,752 psi | 88% | 2920 fps | 100% |
| Vihtavuori N140 | <<locked>> | 88% | 55,753 psi | 89% | 2936 fps | 100% |
| Vihtavuori N150 | <<locked>> | 94% | 55,695 psi | 89% | 2963 fps | 100% |
| Vihtavuori N160 | <<locked>> | 96% | 53,592 psi | 86% | 2995 fps | 99.3% |
| Vihtavuori N530 | <<locked>> | 84% | 55,259 psi | 89% | 2963 fps | 100% |
| Vihtavuori N540 | <<locked>> | 88% | 53,766 psi | 86% | 2930 fps | 100% |
| Vihtavuori N550 | <<locked>> | 98% | 56,362 psi | 90% | 3058 fps | 99.5% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 44,672 psi | 72% | 2920 fps | 98.7% |
| Winchester 6.5 StaBALL | <<locked>> | 96% | 53,998 psi | 87% | 2976 fps | 100% |
| Winchester 748 | <<locked>> | 84% | 55,434 psi | 89% | 3012 fps | 100% |
| Winchester 760 | <<locked>> | 96% | 55,085 psi | 88% | 3064 fps | 97.8% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 36,187 psi | 58% | 2838 fps | 98.7% |
| Winchester StaBALL Match | <<locked>> | 86% | 54,302 psi | 87% | 2992 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% | 49,719 psi | 80% | 2808 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 42,105 psi | 68% | 2723 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 49,792 psi | 80% | 2890 fps | 100% |
| Accurate 2700 | <<locked>> | 84% | 47,776 psi | 77% | 2815 fps | 95.3% |
| Accurate 3100 | <<locked>> | 98% | 39,537 psi | 63% | 2746 fps | 95% |
| Accurate 4064 | <<locked>> | 80% | 39,827 psi | 64% | 2713 fps | 100% |
| Accurate 4350 | <<locked>> | 86% | 36,230 psi | 58% | 2697 fps | 95.8% |
| ADI AR 2206H | <<locked>> | 80% | 45,992 psi | 74% | 2844 fps | 99.2% |
| ADI AR 2208 | <<locked>> | 80% | 39,102 psi | 63% | 2684 fps | 97.3% |
| ADI Benchmark 8208 | <<locked>> | 80% | 48,167 psi | 77% | 2854 fps | 99.9% |
| Alliant AR-Comp | <<locked>> | 80% | 48,733 psi | 78% | 2838 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 42,076 psi | 67% | 2874 fps | 98% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 38,725 psi | 62% | 2707 fps | 98.6% |
| Alliant Reloder-15 | <<locked>> | 80% | 41,597 psi | 67% | 2772 fps | 98.1% |
| Alliant Reloder-16 | <<locked>> | 84% | 34,026 psi | 55% | 2654 fps | 95% |
| Alliant Reloder-17 | <<locked>> | 80% | 33,489 psi | 54% | 2667 fps | 96.7% |
| Alliant Reloder-23 | <<locked>> | 92% | 31,386 psi | 50% | 2605 fps | 95.6% |
| Alliant Reloder-26 | <<locked>> | 94% | 36,709 psi | 59% | 2802 fps | 95.2% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 45,455 psi | 73% | 2848 fps | 98.4% |
| Bofors RP3 | <<locked>> | 80% | 38,363 psi | 62% | 2707 fps | 98.6% |
| Bofors RP7 | <<locked>> | 90% | 47,572 psi | 76% | 2848 fps | 95.5% |
| Hodgdon Benchmark | <<locked>> | 80% | 49,879 psi | 80% | 2844 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 80% | 47,195 psi | 76% | 2874 fps | 100% |
| Hodgdon H380 | <<locked>> | 80% | 39,204 psi | 63% | 2710 fps | 96.2% |
| Hodgdon H414 | <<locked>> | 90% | 44,802 psi | 72% | 2877 fps | 95.5% |
| Hodgdon H4350 | <<locked>> | 90% | 48,791 psi | 78% | 2907 fps | 95% |
| Hodgdon H4895 | <<locked>> | 80% | 46,456 psi | 74% | 2854 fps | 99.5% |
| Hodgdon Hybrid 100V | <<locked>> | 84% | 31,285 psi | 50% | 2549 fps | 95.8% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 42,728 psi | 69% | 2825 fps | 99.4% |
| Hodgdon Superformance | 70.4 gr | 92% | 48,109 psi | 77% | 2969 fps | 95.8% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,353 psi | 42% | 1657 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 44,541 psi | 71% | 2805 fps | 99.3% |
| IMR 3031 | <<locked>> | 80% | 46,224 psi | 74% | 2848 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 41,046 psi | 66% | 2723 fps | 98% |
| IMR 4166 Enduron | <<locked>> | 80% | 43,453 psi | 70% | 2743 fps | 95% |
| IMR 4350 | <<locked>> | 94% | 48,124 psi | 77% | 2881 fps | 95.7% |
| IMR 4451 Enduron | <<locked>> | 88% | 46,615 psi | 75% | 2831 fps | 95.8% |
| IMR 4831 | <<locked>> | 86% | 35,070 psi | 56% | 2651 fps | 95.5% |
| IMR 4895 | <<locked>> | 80% | 42,670 psi | 68% | 2805 fps | 98.7% |
| IMR 8208 XBR | <<locked>> | 80% | 48,167 psi | 77% | 2854 fps | 99.9% |
| Lovex D073.6 | <<locked>> | 80% | 45,281 psi | 73% | 2822 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 45,876 psi | 74% | 2779 fps | 99.2% |
| Lovex S062 | <<locked>> | 80% | 40,857 psi | 66% | 2723 fps | 99.3% |
| Lovex S065 | <<locked>> | 86% | 40,422 psi | 65% | 2713 fps | 95.6% |
| Lovex S070 | <<locked>> | 90% | 43,743 psi | 70% | 2802 fps | 95.4% |
| Norma 201 | <<locked>> | 80% | 44,860 psi | 72% | 2792 fps | 99.7% |
| Norma 202 | <<locked>> | 80% | 45,368 psi | 73% | 2802 fps | 100% |
| Norma 203B | <<locked>> | 80% | 40,988 psi | 66% | 2759 fps | 98.4% |
| Norma 204 | <<locked>> | 96% | 51,735 psi | 83% | 2982 fps | 95.1% |
| Norma URP | <<locked>> | 86% | 36,651 psi | 59% | 2703 fps | 95.8% |
| Ramshot Big Game | <<locked>> | 80% | 40,785 psi | 65% | 2776 fps | 98.2% |
| Ramshot Hunter | <<locked>> | 90% | 40,857 psi | 66% | 2805 fps | 95.2% |
| Ramshot TAC | <<locked>> | 80% | 48,095 psi | 77% | 2861 fps | 97.8% |
| Ramshot Wild Boar | <<locked>> | 80% | 47,834 psi | 77% | 2884 fps | 99.4% |
| Ramshot X-Terminator | <<locked>> | 80% | 51,938 psi | 83% | 2907 fps | 99.7% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 26,760 psi | 43% | 1699 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 82% | 42,322 psi | 68% | 2753 fps | 95.4% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 44,208 psi | 71% | 2884 fps | 98.5% |
| ReloadSwiss RS 60 | 57.9 gr | 80% | 35,679 psi | 57% | 2740 fps | 99.4% |
| ReloadSwiss RS 62 | <<locked>> | 86% | 36,245 psi | 58% | 2717 fps | 95.4% |
| ReloadSwiss RS 70 | 64.7 gr | 88% | 38,841 psi | 62% | 2789 fps | 95.5% |
| Rottweil R 901 | <<locked>> | 80% | 48,602 psi | 78% | 2831 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 42,612 psi | 68% | 2740 fps | 99.5% |
| Rottweil R 903 | <<locked>> | 80% | 36,027 psi | 58% | 2648 fps | 97.8% |
| Rottweil R 907 | <<locked>> | 90% | 47,572 psi | 76% | 2848 fps | 95.5% |
| Shooters World Long Rifle | <<locked>> | 86% | 40,422 psi | 65% | 2713 fps | 95.6% |
| Shooters World Match Rifle | <<locked>> | 80% | 45,281 psi | 73% | 2822 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 40,857 psi | 66% | 2723 fps | 99.3% |
| Shooters World SW4350 | <<locked>> | 90% | 43,743 psi | 70% | 2802 fps | 95.4% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 37,231 psi | 60% | 2700 fps | 97.3% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 46,369 psi | 74% | 2831 fps | 97.9% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 44,556 psi | 71% | 2812 fps | 99% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 46,267 psi | 74% | 2746 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 38,551 psi | 62% | 2605 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 90% | 45,701 psi | 73% | 2772 fps | 95.7% |
| Somchem S321 | <<locked>> | 80% | 52,272 psi | 84% | 2936 fps | 100% |
| Somchem S335 | <<locked>> | 80% | 45,847 psi | 74% | 2746 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 46,253 psi | 74% | 2831 fps | 99.2% |
| Somchem S355 | <<locked>> | 80% | 36,854 psi | 59% | 2654 fps | 97.8% |
| Somchem S365 | <<locked>> | 80% | 26,658 psi | 43% | 2464 fps | 95% |
| Vihtavuori N130 | <<locked>> | 80% | 52,228 psi | 84% | 2808 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 46,702 psi | 75% | 2740 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 42,351 psi | 68% | 2723 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 42,989 psi | 69% | 2733 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 35,114 psi | 56% | 2589 fps | 98.5% |
| Vihtavuori N160 | <<locked>> | 84% | 35,868 psi | 58% | 2651 fps | 95.5% |
| Vihtavuori N530 | <<locked>> | 80% | 48,327 psi | 77% | 2851 fps | 99.9% |
| Vihtavuori N540 | <<locked>> | 80% | 41,423 psi | 66% | 2720 fps | 100% |
| Vihtavuori N550 | <<locked>> | 86% | 37,623 psi | 60% | 2703 fps | 95.9% |
| Vihtavuori N555 | <<locked>> | 92% | 33,997 psi | 55% | 2684 fps | 95.7% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 31,096 psi | 50% | 2507 fps | 95.9% |
| Winchester 748 | <<locked>> | 80% | 48,269 psi | 77% | 2900 fps | 100% |
| Winchester 760 | <<locked>> | 90% | 45,034 psi | 72% | 2884 fps | 95.6% |
| Winchester StaBALL HD | <<locked>> | 94% | 29,675 psi | 48% | 2625 fps | 95.1% |
| Winchester StaBALL Match | <<locked>> | 80% | 44,121 psi | 71% | 2815 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 | 154gr | Hammer HHT. Alliant Power Pro 2000-MR delivers the highest muzzle velocity at 3,143 fps; across all powders the maximum-charge window runs from 1,854 fps to 3,143 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 154.0 gr projectile in 0.308" calls for a 1:11.5 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 60, ReloadSwiss RS 70, Hodgdon Superformance rank at the top here: for .300 H&H Mag. with the .308 | 154gr | Hammer HHT 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.