Load Specifications
Load data in caliber .308 Norma Mag. with .311 | 155gr | Frontier FBSP bullet and 97 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% | 54,679 psi | 86% | 2881 fps | 100% |
| Accurate 2495 | <<locked>> | 88% | 57,348 psi | 90% | 2956 fps | 100% |
| Accurate 2520 | <<locked>> | 82% | 55,027 psi | 86% | 2969 fps | 100% |
| Accurate 2700 | <<locked>> | 88% | 56,014 psi | 88% | 2956 fps | 97.2% |
| Accurate 3100ᴾ | <<locked>> | 100% | 44,469 psi | 70% | 2848 fps | 96.6% |
| Accurate 4064 | <<locked>> | 90% | 57,522 psi | 90% | 3005 fps | 100% |
| Accurate 4350 | <<locked>> | 98% | 57,740 psi | 90% | 3100 fps | 99.8% |
| ADI AR 2206H | <<locked>> | 86% | 57,174 psi | 90% | 3035 fps | 100% |
| ADI AR 2208 | <<locked>> | 90% | 54,926 psi | 86% | 2986 fps | 99.8% |
| ADI Benchmark 8208 | <<locked>> | 84% | 56,028 psi | 88% | 2982 fps | 100% |
| Alliant AR-Comp | <<locked>> | 84% | 57,305 psi | 90% | 2956 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 88% | 57,305 psi | 90% | 3166 fps | 100% |
| Alliant Reloder- TS 15.5 | <<locked>> | 90% | 55,114 psi | 86% | 3009 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 88% | 55,492 psi | 87% | 3028 fps | 99.9% |
| Alliant Reloder-16 | <<locked>> | 98% | 54,839 psi | 86% | 3100 fps | 99.8% |
| Alliant Reloder-17 | <<locked>> | 94% | 56,231 psi | 88% | 3136 fps | 100% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 42,163 psi | 66% | 2877 fps | 99.2% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 47,543 psi | 75% | 3054 fps | 98.7% |
| Baschieri & Pellagri 107 | <<locked>> | 86% | 57,305 psi | 90% | 3054 fps | 99.8% |
| Bofors RP3 | <<locked>> | 90% | 55,825 psi | 87% | 3025 fps | 100% |
| Bofors RP7 | <<locked>> | 94% | 55,724 psi | 87% | 2995 fps | 97.4% |
| Hodgdon Benchmark | <<locked>> | 84% | 57,537 psi | 90% | 2966 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 84% | 55,927 psi | 88% | 3018 fps | 100% |
| Hodgdon H380 | <<locked>> | 90% | 56,710 psi | 89% | 3038 fps | 99.5% |
| Hodgdon H414 | <<locked>> | 96% | 56,463 psi | 88% | 3091 fps | 98.2% |
| Hodgdon H4350 | <<locked>> | 94% | 56,927 psi | 89% | 3051 fps | 97% |
| Hodgdon H4895 | <<locked>> | 84% | 54,273 psi | 85% | 2992 fps | 100% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 54,766 psi | 86% | 3022 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 86% | 53,998 psi | 85% | 3028 fps | 100% |
| Hodgdon Superformance | <<locked>> | 96% | 57,377 psi | 90% | 3133 fps | 98% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 35,766 psi | 56% | 1860 fps | 100% |
| Hodgdon VARGET | <<locked>> | 86% | 55,419 psi | 87% | 2995 fps | 100% |
| IMR 3031 | <<locked>> | 84% | 54,578 psi | 86% | 2979 fps | 100% |
| IMR 4064 | <<locked>> | 88% | 54,273 psi | 85% | 2966 fps | 99.8% |
| IMR 4166 Enduron | <<locked>> | 88% | 57,537 psi | 90% | 2999 fps | 98.2% |
| IMR 4350 | <<locked>> | 98% | 56,101 psi | 88% | 3018 fps | 97.5% |
| IMR 4451 Enduron | <<locked>> | 94% | 57,450 psi | 90% | 3025 fps | 98.1% |
| IMR 4831 | <<locked>> | 98% | 54,230 psi | 85% | 3028 fps | 99.6% |
| IMR 4895 | <<locked>> | 88% | 56,927 psi | 89% | 3061 fps | 100% |
| IMR 8208 XBR | <<locked>> | 84% | 56,028 psi | 88% | 2982 fps | 100% |
| Lovex D073.6 | <<locked>> | 86% | 57,522 psi | 90% | 3015 fps | 100% |
| Lovex S060 | <<locked>> | 86% | 56,449 psi | 88% | 2959 fps | 100% |
| Lovex S062 | <<locked>> | 90% | 57,696 psi | 90% | 3015 fps | 100% |
| Lovex S065 | <<locked>> | 96% | 56,985 psi | 89% | 3018 fps | 99.1% |
| Lovex S070 | <<locked>> | 96% | 54,752 psi | 86% | 3002 fps | 98% |
| Norma 201 | <<locked>> | 86% | 55,883 psi | 88% | 2979 fps | 100% |
| Norma 202 | <<locked>> | 86% | 56,405 psi | 88% | 2979 fps | 100% |
| Norma 203B | <<locked>> | 88% | 54,737 psi | 86% | 3015 fps | 100% |
| Norma 204 | <<locked>> | 98% | 56,942 psi | 89% | 3071 fps | 96.4% |
| Norma MRPᴾ | <<locked>> | 100% | 47,210 psi | 74% | 3005 fps | 96.1% |
| Norma URP | <<locked>> | 98% | 56,260 psi | 88% | 3081 fps | 99.7% |
| Ramshot Big Game | <<locked>> | 88% | 55,434 psi | 87% | 3041 fps | 99.9% |
| Ramshot Hunter | <<locked>> | 98% | 55,129 psi | 86% | 3077 fps | 98.6% |
| Ramshot TAC | <<locked>> | 84% | 56,347 psi | 88% | 3005 fps | 99.1% |
| Ramshot Wild Boar | <<locked>> | 84% | 56,086 psi | 88% | 3022 fps | 100% |
| Ramshot X-Terminator | <<locked>> | 82% | 56,927 psi | 89% | 2986 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 36,172 psi | 57% | 1903 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 90% | 56,753 psi | 89% | 3018 fps | 98.6% |
| ReloadSwiss RS 52 | <<locked>> | 86% | 56,275 psi | 88% | 3100 fps | 99.9% |
| ReloadSwiss RS 60 | <<locked>> | 92% | 55,782 psi | 87% | 3133 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 98% | 57,566 psi | 90% | 3120 fps | 99.7% |
| ReloadSwiss RS 70 | <<locked>> | 98% | 56,536 psi | 89% | 3150 fps | 99.6% |
| Rottweil R 901 | <<locked>> | 84% | 56,811 psi | 89% | 2959 fps | 100% |
| Rottweil R 902 | <<locked>> | 88% | 56,434 psi | 88% | 2976 fps | 100% |
| Rottweil R 903 | <<locked>> | 92% | 55,695 psi | 87% | 3015 fps | 100% |
| Rottweil R 907 | <<locked>> | 94% | 55,724 psi | 87% | 2995 fps | 97.4% |
| Shooters World Long Rifle | <<locked>> | 96% | 56,985 psi | 89% | 3018 fps | 99.1% |
| Shooters World Match Rifle | <<locked>> | 86% | 57,522 psi | 90% | 3015 fps | 100% |
| Shooters World Precision | <<locked>> | 90% | 57,696 psi | 90% | 3015 fps | 100% |
| Shooters World SW4350 | <<locked>> | 96% | 54,752 psi | 86% | 3002 fps | 98% |
| SNPE Vectan SP 11 | <<locked>> | 92% | 57,508 psi | 90% | 3077 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 84% | 54,998 psi | 86% | 2982 fps | 99.2% |
| SNPE Vectan SP 9 | <<locked>> | 86% | 55,738 psi | 87% | 3005 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 86% | 57,334 psi | 90% | 2917 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 92% | 57,638 psi | 90% | 2910 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 96% | 57,232 psi | 90% | 2969 fps | 98.1% |
| Somchem S321 | <<locked>> | 82% | 57,508 psi | 90% | 3018 fps | 100% |
| Somchem S335 | <<locked>> | 86% | 56,666 psi | 89% | 2910 fps | 100% |
| Somchem S341 | <<locked>> | 84% | 54,607 psi | 86% | 2972 fps | 99.9% |
| Somchem S355 | <<locked>> | 92% | 55,840 psi | 88% | 3012 fps | 100% |
| Somchem S365ᴾ | <<locked>> | 100% | 54,621 psi | 86% | 3084 fps | 100% |
| Somchem S385ᴾ | <<locked>> | 100% | 50,488 psi | 79% | 2956 fps | 96.3% |
| Vihtavuori N130 | <<locked>> | 82% | 56,753 psi | 89% | 2871 fps | 100% |
| Vihtavuori N133 | <<locked>> | 86% | 57,624 psi | 90% | 2900 fps | 100% |
| Vihtavuori N135 | <<locked>> | 88% | 56,463 psi | 88% | 2943 fps | 100% |
| Vihtavuori N140 | <<locked>> | 88% | 57,232 psi | 90% | 2959 fps | 100% |
| Vihtavuori N150 | <<locked>> | 94% | 57,450 psi | 90% | 2989 fps | 100% |
| Vihtavuori N160 | <<locked>> | 96% | 55,259 psi | 87% | 3022 fps | 99.5% |
| Vihtavuori N530 | <<locked>> | 84% | 56,710 psi | 89% | 2986 fps | 100% |
| Vihtavuori N540 | <<locked>> | 88% | 55,434 psi | 87% | 2956 fps | 100% |
| Vihtavuori N550 | <<locked>> | 96% | 54,201 psi | 85% | 3025 fps | 99.4% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 46,557 psi | 73% | 2959 fps | 99.1% |
| Winchester 6.5 StaBALL | <<locked>> | 96% | 55,405 psi | 87% | 2999 fps | 100% |
| Winchester 748 | <<locked>> | 84% | 56,942 psi | 89% | 3035 fps | 100% |
| Winchester 760 | <<locked>> | 96% | 56,724 psi | 89% | 3094 fps | 98.2% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 37,884 psi | 59% | 2890 fps | 99.3% |
| Winchester StaBALL Match | <<locked>> | 86% | 55,724 psi | 87% | 3015 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% | 51,242 psi | 80% | 2831 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 44,077 psi | 69% | 2753 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 51,547 psi | 81% | 2917 fps | 100% |
| Accurate 2700 | <<locked>> | 84% | 49,153 psi | 77% | 2838 fps | 95.7% |
| Accurate 3100 | <<locked>> | 98% | 41,481 psi | 65% | 2789 fps | 95.7% |
| Accurate 4064 | <<locked>> | 80% | 41,684 psi | 65% | 2749 fps | 100% |
| Accurate 4350 | <<locked>> | 84% | 35,418 psi | 56% | 2677 fps | 95.6% |
| ADI AR 2206H | <<locked>> | 80% | 47,311 psi | 74% | 2867 fps | 99.4% |
| ADI AR 2208 | <<locked>> | 80% | 40,248 psi | 63% | 2710 fps | 97.7% |
| ADI Benchmark 8208 | <<locked>> | 80% | 49,356 psi | 77% | 2874 fps | 100% |
| Alliant AR-Comp | <<locked>> | 80% | 50,227 psi | 79% | 2858 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 43,424 psi | 68% | 2907 fps | 98.4% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 40,059 psi | 63% | 2733 fps | 98.9% |
| Alliant Reloder-15 | <<locked>> | 80% | 42,917 psi | 67% | 2802 fps | 98.4% |
| Alliant Reloder-16 | <<locked>> | 84% | 35,331 psi | 55% | 2690 fps | 95.7% |
| Alliant Reloder-17 | 58.5 gr | 80% | 34,809 psi | 55% | 2703 fps | 97.3% |
| Alliant Reloder-23 | <<locked>> | 90% | 30,850 psi | 48% | 2589 fps | 95.5% |
| Alliant Reloder-26 | <<locked>> | 94% | 38,305 psi | 60% | 2848 fps | 96.1% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 46,818 psi | 73% | 2874 fps | 98.7% |
| Bofors RP3 | <<locked>> | 80% | 40,103 psi | 63% | 2743 fps | 99% |
| Bofors RP7 | <<locked>> | 88% | 46,180 psi | 72% | 2825 fps | 95.3% |
| Hodgdon Benchmark | <<locked>> | 80% | 51,024 psi | 80% | 2864 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 80% | 48,762 psi | 76% | 2904 fps | 100% |
| Hodgdon H380 | <<locked>> | 80% | 40,770 psi | 64% | 2746 fps | 96.8% |
| Hodgdon H414 | <<locked>> | 88% | 43,279 psi | 68% | 2851 fps | 95.2% |
| Hodgdon H4350 | <<locked>> | 90% | 50,082 psi | 78% | 2933 fps | 95.5% |
| Hodgdon H4895 | <<locked>> | 80% | 47,761 psi | 75% | 2881 fps | 99.7% |
| Hodgdon Hybrid 100V | <<locked>> | 82% | 30,560 psi | 48% | 2526 fps | 95.7% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 43,990 psi | 69% | 2851 fps | 99.6% |
| Hodgdon Superformance | 69.5 gr | 90% | 46,035 psi | 72% | 2930 fps | 95.4% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,643 psi | 42% | 1663 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 45,934 psi | 72% | 2831 fps | 99.5% |
| IMR 3031 | <<locked>> | 80% | 47,906 psi | 75% | 2877 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 42,293 psi | 66% | 2746 fps | 98.4% |
| IMR 4166 Enduron | <<locked>> | 80% | 44,759 psi | 70% | 2772 fps | 95.5% |
| IMR 4350 | <<locked>> | 92% | 46,615 psi | 73% | 2854 fps | 95.4% |
| IMR 4451 Enduron | <<locked>> | 86% | 44,962 psi | 70% | 2802 fps | 95.4% |
| IMR 4831 | <<locked>> | 84% | 34,389 psi | 54% | 2635 fps | 95.4% |
| IMR 4895 | <<locked>> | 80% | 44,005 psi | 69% | 2835 fps | 99% |
| IMR 8208 XBR | <<locked>> | 80% | 49,356 psi | 77% | 2874 fps | 100% |
| Lovex D073.6 | <<locked>> | 80% | 46,833 psi | 73% | 2848 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 46,978 psi | 74% | 2802 fps | 99.4% |
| Lovex S062 | <<locked>> | 80% | 42,279 psi | 66% | 2749 fps | 99.5% |
| Lovex S065 | <<locked>> | 84% | 39,523 psi | 62% | 2690 fps | 95.5% |
| Lovex S070 | <<locked>> | 88% | 42,641 psi | 67% | 2776 fps | 95.2% |
| Norma 201 | <<locked>> | 80% | 46,325 psi | 73% | 2818 fps | 99.8% |
| Norma 202 | <<locked>> | 80% | 46,731 psi | 73% | 2825 fps | 100% |
| Norma 203B | <<locked>> | 80% | 42,308 psi | 66% | 2789 fps | 98.7% |
| Norma 204 | <<locked>> | 96% | 53,287 psi | 84% | 3012 fps | 95.6% |
| Norma MRP | <<locked>> | 98% | 44,164 psi | 69% | 2940 fps | 95.1% |
| Norma URP | <<locked>> | 84% | 35,636 psi | 56% | 2677 fps | 95.6% |
| Ramshot Big Game | <<locked>> | 80% | 42,206 psi | 66% | 2805 fps | 98.6% |
| Ramshot Hunter | <<locked>> | 90% | 42,438 psi | 67% | 2838 fps | 95.9% |
| Ramshot TAC | <<locked>> | 80% | 49,429 psi | 77% | 2884 fps | 98.1% |
| Ramshot Wild Boar | <<locked>> | 80% | 49,226 psi | 77% | 2907 fps | 99.6% |
| Ramshot X-Terminator | <<locked>> | 80% | 53,287 psi | 84% | 2927 fps | 99.8% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 26,905 psi | 42% | 1703 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 41,046 psi | 64% | 2726 fps | 95.1% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 45,759 psi | 72% | 2917 fps | 98.9% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 37,043 psi | 58% | 2772 fps | 99.7% |
| ReloadSwiss RS 62 | <<locked>> | 84% | 35,143 psi | 55% | 2690 fps | 95.1% |
| ReloadSwiss RS 70 | 63.8 gr | 86% | 37,463 psi | 59% | 2759 fps | 95.1% |
| Rottweil R 901 | <<locked>> | 80% | 50,531 psi | 79% | 2864 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 44,092 psi | 69% | 2766 fps | 99.7% |
| Rottweil R 903 | <<locked>> | 80% | 37,550 psi | 59% | 2680 fps | 98.3% |
| Rottweil R 907 | <<locked>> | 88% | 46,180 psi | 72% | 2825 fps | 95.3% |
| Shooters World Long Rifle | <<locked>> | 84% | 39,523 psi | 62% | 2690 fps | 95.5% |
| Shooters World Match Rifle | <<locked>> | 80% | 46,833 psi | 73% | 2848 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 42,279 psi | 66% | 2749 fps | 99.5% |
| Shooters World SW4350 | <<locked>> | 88% | 42,641 psi | 67% | 2776 fps | 95.2% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 38,653 psi | 61% | 2736 fps | 97.9% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 47,906 psi | 75% | 2861 fps | 98.3% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 45,963 psi | 72% | 2838 fps | 99.2% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 47,529 psi | 74% | 2766 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 39,769 psi | 62% | 2625 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 88% | 44,338 psi | 69% | 2746 fps | 95.4% |
| Somchem S321 | <<locked>> | 80% | 53,795 psi | 84% | 2959 fps | 100% |
| Somchem S335 | <<locked>> | 80% | 47,181 psi | 74% | 2766 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 47,659 psi | 75% | 2858 fps | 99.4% |
| Somchem S355 | <<locked>> | 80% | 38,261 psi | 60% | 2687 fps | 98.3% |
| Somchem S365 | <<locked>> | 80% | 27,949 psi | 44% | 2507 fps | 96% |
| Somchem S385 | <<locked>> | 98% | 47,311 psi | 74% | 2900 fps | 95.6% |
| Vihtavuori N130 | <<locked>> | 80% | 53,490 psi | 84% | 2825 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 47,935 psi | 75% | 2759 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 43,816 psi | 69% | 2746 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 44,266 psi | 69% | 2756 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 36,419 psi | 57% | 2618 fps | 98.9% |
| Vihtavuori N160 | <<locked>> | 82% | 34,693 psi | 54% | 2621 fps | 95.1% |
| Vihtavuori N530 | <<locked>> | 80% | 49,792 psi | 78% | 2877 fps | 100% |
| Vihtavuori N540 | <<locked>> | 80% | 42,873 psi | 67% | 2746 fps | 100% |
| Vihtavuori N550 | <<locked>> | 84% | 36,666 psi | 57% | 2680 fps | 95.7% |
| Vihtavuori N555 | <<locked>> | 90% | 33,431 psi | 52% | 2671 fps | 95.6% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 32,300 psi | 51% | 2539 fps | 96.6% |
| Winchester 748 | <<locked>> | 80% | 49,792 psi | 78% | 2923 fps | 100% |
| Winchester 760 | <<locked>> | 88% | 43,511 psi | 68% | 2854 fps | 95.2% |
| Winchester StaBALL HD | <<locked>> | 94% | 30,966 psi | 49% | 2674 fps | 96.3% |
| Winchester StaBALL Match | <<locked>> | 80% | 45,600 psi | 71% | 2841 fps | 99.5% |
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 97 powders for .308 Norma Mag. loaded with the .311 | 155gr | Frontier FBSP. Alliant Power Pro 2000-MR delivers the highest muzzle velocity at 3,166 fps; across all powders the maximum-charge window runs from 1,860 fps to 3,166 fps. Accurate 3100 gives the best case fill at 100 %, and 97 of the 97 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (440 MPa), the top charges use 56–90 %, leaving at least 10 % headroom. The 155.0 gr projectile in 0.311" 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 .308 Norma Mag. with the .311 | 155gr | Frontier FBSP 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.