Load Specifications
Load data in caliber .300 H&H Mag. with .306 | 155gr | Fox Classic Hunter bullet and 96 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.
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>> | 82% | 53,040 psi | 85% | 2848 fps | 100% |
| Accurate 2495 | <<locked>> | 88% | 55,245 psi | 89% | 2917 fps | 100% |
| Accurate 2520 | <<locked>> | 82% | 53,664 psi | 86% | 2940 fps | 100% |
| Accurate 2700 | <<locked>> | 88% | 54,810 psi | 88% | 2927 fps | 96.9% |
| Accurate 3100ᴾ | <<locked>> | 100% | 42,743 psi | 69% | 2805 fps | 96.1% |
| Accurate 4064 | <<locked>> | 90% | 55,550 psi | 89% | 2969 fps | 100% |
| Accurate 4350 | <<locked>> | 98% | 55,883 psi | 90% | 3061 fps | 99.6% |
| ADI AR 2206H | <<locked>> | 86% | 56,057 psi | 90% | 3009 fps | 100% |
| ADI AR 2208 | <<locked>> | 90% | 53,722 psi | 86% | 2953 fps | 99.7% |
| ADI Benchmark 8208 | <<locked>> | 84% | 54,940 psi | 88% | 2956 fps | 100% |
| Alliant AR-Comp | <<locked>> | 84% | 55,970 psi | 90% | 2930 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 88% | 56,101 psi | 90% | 3133 fps | 99.9% |
| Alliant Reloder- TS 15.5 | <<locked>> | 90% | 53,708 psi | 86% | 2976 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 88% | 54,114 psi | 87% | 2995 fps | 99.8% |
| Alliant Reloder-16 | <<locked>> | 98% | 53,664 psi | 86% | 3068 fps | 99.7% |
| Alliant Reloder-17 | <<locked>> | 94% | 54,737 psi | 88% | 3100 fps | 100% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 40,727 psi | 65% | 2835 fps | 98.9% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 46,035 psi | 74% | 3012 fps | 98.4% |
| Baschieri & Pellagri 107 | <<locked>> | 86% | 56,115 psi | 90% | 3022 fps | 99.7% |
| Bofors RP3 | <<locked>> | 90% | 54,288 psi | 87% | 2989 fps | 100% |
| Bofors RP7 | <<locked>> | 94% | 54,418 psi | 87% | 2959 fps | 97.1% |
| Hodgdon Benchmark | <<locked>> | 82% | 53,026 psi | 85% | 2884 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 84% | 54,491 psi | 87% | 2986 fps | 100% |
| Hodgdon H380 | <<locked>> | 90% | 55,303 psi | 89% | 3005 fps | 99.3% |
| Hodgdon H414 | <<locked>> | 96% | 55,259 psi | 89% | 3061 fps | 97.9% |
| Hodgdon H4350 | <<locked>> | 94% | 55,738 psi | 89% | 3018 fps | 96.7% |
| Hodgdon H4895 | <<locked>> | 84% | 53,098 psi | 85% | 2963 fps | 100% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 53,490 psi | 86% | 2992 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 88% | 56,304 psi | 90% | 3051 fps | 100% |
| Hodgdon Superformance | <<locked>> | 96% | 55,840 psi | 90% | 3094 fps | 97.7% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 35,447 psi | 57% | 1847 fps | 100% |
| Hodgdon VARGET | <<locked>> | 86% | 54,433 psi | 87% | 2966 fps | 100% |
| IMR 3031 | <<locked>> | 84% | 53,055 psi | 85% | 2946 fps | 100% |
| IMR 4064 | <<locked>> | 88% | 53,229 psi | 85% | 2940 fps | 99.7% |
| IMR 4166 Enduron | <<locked>> | 88% | 56,376 psi | 90% | 2969 fps | 97.9% |
| IMR 4350 | <<locked>> | 98% | 54,969 psi | 88% | 2989 fps | 97.3% |
| IMR 4451 Enduron | <<locked>> | 94% | 56,362 psi | 90% | 2995 fps | 97.9% |
| IMR 4831 | <<locked>> | 98% | 52,895 psi | 85% | 2995 fps | 99.4% |
| IMR 4895 | <<locked>> | 88% | 55,521 psi | 89% | 3028 fps | 100% |
| IMR 8208 XBR | <<locked>> | 84% | 54,940 psi | 88% | 2956 fps | 100% |
| Lovex D073.6 | <<locked>> | 86% | 55,898 psi | 90% | 2982 fps | 100% |
| Lovex S060 | <<locked>> | 86% | 55,259 psi | 89% | 2930 fps | 99.9% |
| Lovex S062 | <<locked>> | 90% | 56,260 psi | 90% | 2982 fps | 100% |
| Lovex S065 | <<locked>> | 96% | 55,622 psi | 89% | 2986 fps | 98.9% |
| Lovex S070 | <<locked>> | 96% | 53,156 psi | 85% | 2963 fps | 97.6% |
| Norma 201 | <<locked>> | 86% | 54,563 psi | 87% | 2949 fps | 100% |
| Norma 202 | <<locked>> | 86% | 55,245 psi | 89% | 2949 fps | 100% |
| Norma 203B | <<locked>> | 88% | 53,330 psi | 86% | 2982 fps | 99.9% |
| Norma 204 | <<locked>> | 98% | 55,564 psi | 89% | 3038 fps | 96% |
| Norma URP | <<locked>> | 98% | 54,998 psi | 88% | 3048 fps | 99.5% |
| Ramshot Big Game | <<locked>> | 88% | 54,172 psi | 87% | 3009 fps | 99.9% |
| Ramshot Hunter | <<locked>> | 98% | 53,737 psi | 86% | 3041 fps | 98.4% |
| Ramshot TAC | <<locked>> | 84% | 55,172 psi | 88% | 2972 fps | 98.9% |
| Ramshot Wild Boar | <<locked>> | 84% | 54,824 psi | 88% | 2989 fps | 99.9% |
| Ramshot X-Terminator | <<locked>> | 82% | 55,666 psi | 89% | 2953 fps | 99.9% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 36,013 psi | 58% | 1893 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 90% | 55,506 psi | 89% | 2986 fps | 98.3% |
| ReloadSwiss RS 52 | <<locked>> | 86% | 54,839 psi | 88% | 3064 fps | 99.8% |
| ReloadSwiss RS 60 | <<locked>> | 92% | 54,549 psi | 87% | 3104 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 98% | 55,970 psi | 90% | 3087 fps | 99.6% |
| ReloadSwiss RS 70 | <<locked>> | 98% | 55,245 psi | 89% | 3114 fps | 99.4% |
| Rottweil R 901 | <<locked>> | 84% | 55,274 psi | 89% | 2930 fps | 100% |
| Rottweil R 902 | <<locked>> | 88% | 55,114 psi | 88% | 2946 fps | 100% |
| Rottweil R 903 | <<locked>> | 92% | 54,099 psi | 87% | 2979 fps | 100% |
| Rottweil R 907 | <<locked>> | 94% | 54,418 psi | 87% | 2959 fps | 97.1% |
| Shooters World Long Rifle | <<locked>> | 96% | 55,622 psi | 89% | 2986 fps | 98.9% |
| Shooters World Match Rifle | <<locked>> | 86% | 55,898 psi | 90% | 2982 fps | 100% |
| Shooters World Precision | <<locked>> | 90% | 56,260 psi | 90% | 2982 fps | 100% |
| Shooters World SW4350 | <<locked>> | 96% | 53,156 psi | 85% | 2963 fps | 97.6% |
| SNPE Vectan SP 11 | <<locked>> | 92% | 56,260 psi | 90% | 3048 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 84% | 53,606 psi | 86% | 2949 fps | 99.1% |
| SNPE Vectan SP 9 | <<locked>> | 86% | 54,476 psi | 87% | 2976 fps | 99.9% |
| SNPE Vectan Tubal 3000 | <<locked>> | 86% | 55,956 psi | 90% | 2887 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 92% | 56,405 psi | 90% | 2884 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 96% | 56,014 psi | 90% | 2940 fps | 97.9% |
| Somchem S321 | <<locked>> | 82% | 56,144 psi | 90% | 2986 fps | 100% |
| Somchem S335 | <<locked>> | 86% | 55,477 psi | 89% | 2884 fps | 100% |
| Somchem S341 | <<locked>> | 84% | 53,359 psi | 86% | 2943 fps | 99.8% |
| Somchem S355 | <<locked>> | 92% | 54,389 psi | 87% | 2979 fps | 100% |
| Somchem S365ᴾ | <<locked>> | 100% | 53,040 psi | 85% | 3048 fps | 100% |
| Somchem S385ᴾ | <<locked>> | 100% | 49,211 psi | 79% | 2923 fps | 96% |
| Vihtavuori N130 | <<locked>> | 82% | 55,550 psi | 89% | 2844 fps | 100% |
| Vihtavuori N133 | <<locked>> | 86% | 56,275 psi | 90% | 2871 fps | 100% |
| Vihtavuori N135 | <<locked>> | 88% | 54,882 psi | 88% | 2910 fps | 100% |
| Vihtavuori N140 | <<locked>> | 88% | 55,927 psi | 90% | 2930 fps | 100% |
| Vihtavuori N150 | <<locked>> | 94% | 56,130 psi | 90% | 2959 fps | 100% |
| Vihtavuori N160 | <<locked>> | 96% | 53,737 psi | 86% | 2989 fps | 99.4% |
| Vihtavuori N530 | <<locked>> | 84% | 55,361 psi | 89% | 2953 fps | 100% |
| Vihtavuori N540 | <<locked>> | 88% | 54,128 psi | 87% | 2923 fps | 100% |
| Vihtavuori N550 | <<locked>> | 96% | 52,924 psi | 85% | 2992 fps | 99.2% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 45,092 psi | 72% | 2920 fps | 98.8% |
| Winchester 6.5 StaBALL | <<locked>> | 96% | 54,172 psi | 87% | 2966 fps | 100% |
| Winchester 748 | <<locked>> | 84% | 55,622 psi | 89% | 3005 fps | 100% |
| Winchester 760 | <<locked>> | 96% | 55,259 psi | 89% | 3061 fps | 97.9% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 36,521 psi | 59% | 2841 fps | 98.9% |
| Winchester StaBALL Match | <<locked>> | 86% | 54,433 psi | 87% | 2982 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% | 49,821 psi | 80% | 2802 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 42,192 psi | 68% | 2713 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 49,951 psi | 80% | 2881 fps | 100% |
| Accurate 2700 | <<locked>> | 84% | 47,877 psi | 77% | 2805 fps | 95.4% |
| Accurate 3100 | <<locked>> | 98% | 39,740 psi | 64% | 2743 fps | 95.1% |
| Accurate 4064 | <<locked>> | 80% | 39,943 psi | 64% | 2710 fps | 100% |
| Accurate 4350 | <<locked>> | 84% | 33,997 psi | 55% | 2631 fps | 95% |
| ADI AR 2206H | <<locked>> | 80% | 46,093 psi | 74% | 2835 fps | 99.2% |
| ADI AR 2208 | <<locked>> | 80% | 39,160 psi | 63% | 2677 fps | 97.4% |
| ADI Benchmark 8208 | <<locked>> | 80% | 48,240 psi | 77% | 2848 fps | 99.9% |
| Alliant AR-Comp | <<locked>> | 80% | 48,863 psi | 78% | 2828 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 42,192 psi | 68% | 2867 fps | 98.1% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 38,841 psi | 62% | 2697 fps | 98.7% |
| Alliant Reloder-15 | <<locked>> | 80% | 41,713 psi | 67% | 2766 fps | 98.1% |
| Alliant Reloder-16 | <<locked>> | 84% | 34,272 psi | 55% | 2651 fps | 95.1% |
| Alliant Reloder-17 | 57.8 gr | 80% | 33,562 psi | 54% | 2661 fps | 96.8% |
| Alliant Reloder-23 | <<locked>> | 92% | 31,488 psi | 50% | 2598 fps | 95.7% |
| Alliant Reloder-26 | <<locked>> | 94% | 36,840 psi | 59% | 2799 fps | 95.4% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 45,571 psi | 73% | 2841 fps | 98.4% |
| Bofors RP3 | <<locked>> | 80% | 38,464 psi | 62% | 2700 fps | 98.7% |
| Bofors RP7 | <<locked>> | 90% | 47,935 psi | 77% | 2844 fps | 95.6% |
| Hodgdon Benchmark | <<locked>> | 80% | 49,937 psi | 80% | 2835 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 80% | 47,297 psi | 76% | 2867 fps | 100% |
| Hodgdon H380 | <<locked>> | 80% | 39,320 psi | 63% | 2703 fps | 96.3% |
| Hodgdon H414 | <<locked>> | 90% | 44,933 psi | 72% | 2874 fps | 95.6% |
| Hodgdon H4350 | <<locked>> | 90% | 48,907 psi | 78% | 2900 fps | 95.1% |
| Hodgdon H4895 | <<locked>> | 80% | 46,528 psi | 75% | 2848 fps | 99.6% |
| Hodgdon Hybrid 100V | <<locked>> | 82% | 29,414 psi | 47% | 2487 fps | 95% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 42,830 psi | 69% | 2818 fps | 99.4% |
| Hodgdon Superformance | 70.3 gr | 92% | 48,327 psi | 77% | 2963 fps | 96% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,411 psi | 42% | 1654 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 44,643 psi | 72% | 2799 fps | 99.3% |
| IMR 3031 | <<locked>> | 80% | 46,557 psi | 75% | 2844 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 41,133 psi | 66% | 2713 fps | 98.1% |
| IMR 4166 Enduron | <<locked>> | 80% | 43,714 psi | 70% | 2740 fps | 95.1% |
| IMR 4350 | <<locked>> | 94% | 48,298 psi | 77% | 2874 fps | 95.8% |
| IMR 4451 Enduron | <<locked>> | 86% | 44,005 psi | 71% | 2772 fps | 95.1% |
| IMR 4831 | <<locked>> | 86% | 35,360 psi | 57% | 2648 fps | 95.6% |
| IMR 4895 | <<locked>> | 80% | 42,743 psi | 69% | 2795 fps | 98.8% |
| IMR 8208 XBR | <<locked>> | 80% | 48,240 psi | 77% | 2848 fps | 99.9% |
| Lovex D073.6 | <<locked>> | 80% | 45,411 psi | 73% | 2812 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 45,934 psi | 74% | 2772 fps | 99.3% |
| Lovex S062 | <<locked>> | 80% | 40,959 psi | 66% | 2713 fps | 99.3% |
| Lovex S065 | <<locked>> | 86% | 40,712 psi | 65% | 2710 fps | 95.8% |
| Lovex S070 | <<locked>> | 90% | 43,845 psi | 70% | 2792 fps | 95.5% |
| Norma 201 | <<locked>> | 80% | 44,962 psi | 72% | 2782 fps | 99.7% |
| Norma 202 | <<locked>> | 80% | 45,455 psi | 73% | 2792 fps | 100% |
| Norma 203B | <<locked>> | 80% | 41,075 psi | 66% | 2753 fps | 98.4% |
| Norma 204 | <<locked>> | 96% | 51,924 psi | 83% | 2976 fps | 95.2% |
| Norma URP | <<locked>> | 84% | 34,447 psi | 55% | 2641 fps | 95% |
| Ramshot Big Game | <<locked>> | 80% | 40,886 psi | 66% | 2769 fps | 98.3% |
| Ramshot Hunter | <<locked>> | 90% | 41,017 psi | 66% | 2799 fps | 95.3% |
| Ramshot TAC | <<locked>> | 80% | 48,182 psi | 77% | 2851 fps | 97.8% |
| Ramshot Wild Boar | <<locked>> | 80% | 47,921 psi | 77% | 2874 fps | 99.4% |
| Ramshot X-Terminator | <<locked>> | 80% | 52,025 psi | 83% | 2897 fps | 99.7% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 26,629 psi | 43% | 1690 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 82% | 42,612 psi | 68% | 2749 fps | 95.5% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 44,309 psi | 71% | 2877 fps | 98.6% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 35,781 psi | 57% | 2733 fps | 99.5% |
| ReloadSwiss RS 62 | <<locked>> | 86% | 36,347 psi | 58% | 2713 fps | 95.5% |
| ReloadSwiss RS 70 | 64.6 gr | 88% | 38,957 psi | 62% | 2785 fps | 95.7% |
| Rottweil R 901 | <<locked>> | 80% | 48,921 psi | 78% | 2828 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 42,685 psi | 68% | 2733 fps | 99.5% |
| Rottweil R 903 | <<locked>> | 80% | 36,100 psi | 58% | 2641 fps | 97.9% |
| Rottweil R 907 | <<locked>> | 90% | 47,935 psi | 77% | 2844 fps | 95.6% |
| Shooters World Long Rifle | <<locked>> | 86% | 40,712 psi | 65% | 2710 fps | 95.8% |
| Shooters World Match Rifle | <<locked>> | 80% | 45,411 psi | 73% | 2812 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 40,959 psi | 66% | 2713 fps | 99.3% |
| Shooters World SW4350 | <<locked>> | 90% | 43,845 psi | 70% | 2792 fps | 95.5% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 37,333 psi | 60% | 2694 fps | 97.4% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 46,470 psi | 75% | 2825 fps | 98% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 44,657 psi | 72% | 2802 fps | 99% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 46,354 psi | 74% | 2736 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 38,624 psi | 62% | 2595 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 88% | 42,975 psi | 69% | 2710 fps | 95% |
| Somchem S321 | <<locked>> | 80% | 52,373 psi | 84% | 2927 fps | 100% |
| Somchem S335 | <<locked>> | 80% | 45,934 psi | 74% | 2736 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 46,383 psi | 74% | 2825 fps | 99.2% |
| Somchem S355 | <<locked>> | 80% | 36,927 psi | 59% | 2648 fps | 97.9% |
| Somchem S365 | <<locked>> | 80% | 26,745 psi | 43% | 2457 fps | 95.1% |
| Somchem S385 | <<locked>> | 98% | 45,963 psi | 74% | 2864 fps | 95.1% |
| Vihtavuori N130 | <<locked>> | 80% | 52,272 psi | 84% | 2799 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 46,775 psi | 75% | 2730 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 42,453 psi | 68% | 2717 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 43,076 psi | 69% | 2726 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 35,186 psi | 56% | 2582 fps | 98.6% |
| Vihtavuori N160 | <<locked>> | 84% | 35,955 psi | 58% | 2644 fps | 95.5% |
| Vihtavuori N530 | <<locked>> | 80% | 48,399 psi | 78% | 2844 fps | 99.9% |
| Vihtavuori N540 | <<locked>> | 80% | 41,495 psi | 67% | 2710 fps | 100% |
| Vihtavuori N550 | <<locked>> | 84% | 35,302 psi | 57% | 2641 fps | 95.1% |
| Vihtavuori N555 | <<locked>> | 92% | 34,316 psi | 55% | 2684 fps | 95.9% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 31,169 psi | 50% | 2500 fps | 96.1% |
| Winchester 748 | <<locked>> | 80% | 48,428 psi | 78% | 2890 fps | 100% |
| Winchester 760 | <<locked>> | 90% | 45,150 psi | 72% | 2877 fps | 95.6% |
| Winchester StaBALL HD | <<locked>> | 94% | 29,805 psi | 48% | 2621 fps | 95.3% |
| Winchester StaBALL Match | <<locked>> | 80% | 44,251 psi | 71% | 2808 fps | 99.4% |
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 96 powders for .300 H&H Mag. loaded with the .306 | 155gr | Fox Classic Hunter. Alliant Power Pro 2000-MR delivers the highest muzzle velocity at 3,133 fps; across all powders the maximum-charge window runs from 1,847 fps to 3,133 fps. Accurate 3100 gives the best case fill at 100 %, and 96 of the 96 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 155.0 gr projectile in 0.306" 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 70, Hodgdon Superformance, Alliant Reloder-17 rank at the top here: for .300 H&H Mag. with the .306 | 155gr | Fox Classic Hunter 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.