Load Specifications
Load data in caliber 6.8 Western with .277 | 145gr | Fox Classic Hunter bullet and 97 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Alliant Reloder-26, Norma MRP and Vihtavuori N560.
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 2495 | <<locked>> | 82% | 56,362 psi | 87% | 2789 fps | 100% |
| Accurate 2700 | <<locked>> | 84% | 58,146 psi | 89% | 2881 fps | 99.4% |
| Accurate 3100ᴾ | <<locked>> | 100% | 56,536 psi | 87% | 2927 fps | 99.9% |
| Accurate 4064 | <<locked>> | 84% | 56,840 psi | 87% | 2848 fps | 100% |
| Accurate 4350 | <<locked>> | 92% | 58,653 psi | 90% | 2972 fps | 100% |
| Accurate MAGPRO | <<locked>> | 98% | 55,172 psi | 85% | 3015 fps | 96.8% |
| ADI AR 2208 | <<locked>> | 86% | 57,435 psi | 88% | 2894 fps | 100% |
| ADI AR 2209 | <<locked>> | 96% | 55,753 psi | 86% | 2966 fps | 98.7% |
| ADI AR 2213ᴾ | <<locked>> | 100% | 57,145 psi | 88% | 3022 fps | 98% |
| Alliant Power Pro 2000-MR | <<locked>> | 82% | 57,276 psi | 88% | 3018 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 96% | 56,086 psi | 86% | 2966 fps | 98.8% |
| Alliant Reloder- TS 15.5 | <<locked>> | 86% | 58,334 psi | 90% | 2913 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 84% | 58,465 psi | 90% | 2936 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 92% | 55,767 psi | 86% | 2976 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 88% | 57,246 psi | 88% | 2999 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 96% | 55,303 psi | 85% | 2956 fps | 98.7% |
| Alliant Reloder-22ᴾ | <<locked>> | 100% | 56,260 psi | 87% | 3015 fps | 99% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 53,272 psi | 82% | 2936 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 46,035 psi | 71% | 2871 fps | 99.7% |
| Alliant Reloder-26 | <<locked>> | 98% | 57,682 psi | 89% | 3087 fps | 100% |
| Bofors RP15ᴾ | <<locked>> | 100% | 51,619 psi | 79% | 2940 fps | 98.2% |
| Bofors RP3 | <<locked>> | 84% | 55,521 psi | 85% | 2877 fps | 100% |
| Bofors RP5ᴾ | <<locked>> | 100% | 56,260 psi | 87% | 3015 fps | 99% |
| Bofors RP7 | <<locked>> | 90% | 58,392 psi | 90% | 2923 fps | 99.5% |
| Hodgdon H1000ᴾ | <<locked>> | 100% | 45,788 psi | 70% | 2812 fps | 96.3% |
| Hodgdon H380 | <<locked>> | 84% | 55,709 psi | 86% | 2897 fps | 100% |
| Hodgdon H414 | <<locked>> | 90% | 57,000 psi | 88% | 2972 fps | 99.7% |
| Hodgdon H4350 | <<locked>> | 88% | 56,652 psi | 87% | 2933 fps | 99% |
| Hodgdon H4831 | <<locked>> | 98% | 57,493 psi | 88% | 2966 fps | 97.5% |
| Hodgdon H4831 SC | <<locked>> | 98% | 56,275 psi | 87% | 2946 fps | 97.2% |
| Hodgdon Hybrid 100V | <<locked>> | 94% | 55,970 psi | 86% | 2894 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 82% | 57,261 psi | 88% | 2930 fps | 100% |
| Hodgdon Retumboᴾ | <<locked>> | 100% | 45,092 psi | 69% | 2910 fps | 97.7% |
| Hodgdon Superformance | <<locked>> | 90% | 57,522 psi | 88% | 3015 fps | 99.7% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,434 psi | 56% | 1801 fps | 100% |
| Hodgdon VARGET | <<locked>> | 82% | 57,798 psi | 89% | 2894 fps | 100% |
| IMR 4064 | <<locked>> | 84% | 56,579 psi | 87% | 2871 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 82% | 55,622 psi | 86% | 2858 fps | 99.6% |
| IMR 4350 | <<locked>> | 92% | 56,159 psi | 86% | 2907 fps | 99.4% |
| IMR 4451 Enduron | <<locked>> | 88% | 56,478 psi | 87% | 2894 fps | 99.6% |
| IMR 4831 | <<locked>> | 94% | 58,784 psi | 90% | 2959 fps | 100% |
| IMR 4895 | <<locked>> | 82% | 56,130 psi | 86% | 2910 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 96% | 55,071 psi | 85% | 2894 fps | 97.2% |
| IMR 7828 SSCᴾ | <<locked>> | 100% | 54,534 psi | 84% | 2992 fps | 97.7% |
| Lovex S060 | <<locked>> | 82% | 57,957 psi | 89% | 2854 fps | 100% |
| Lovex S062 | <<locked>> | 84% | 56,971 psi | 88% | 2864 fps | 100% |
| Lovex S065 | <<locked>> | 90% | 56,579 psi | 87% | 2890 fps | 100% |
| Lovex S070 | <<locked>> | 92% | 58,175 psi | 89% | 2936 fps | 99.8% |
| Lovex S071ᴾ | <<locked>> | 100% | 46,775 psi | 72% | 2772 fps | 99.2% |
| Norma 201 | <<locked>> | 82% | 57,957 psi | 89% | 2871 fps | 100% |
| Norma 203B | <<locked>> | 84% | 57,740 psi | 89% | 2920 fps | 100% |
| Norma 204 | <<locked>> | 92% | 56,884 psi | 88% | 2959 fps | 98.8% |
| Norma MRP | <<locked>> | 98% | 56,188 psi | 86% | 3045 fps | 99.7% |
| Norma URP | <<locked>> | 92% | 57,276 psi | 88% | 2959 fps | 100% |
| Ramshot Big Game | <<locked>> | 82% | 55,071 psi | 85% | 2897 fps | 100% |
| Ramshot Grandᴾ | <<locked>> | 100% | 55,085 psi | 85% | 3012 fps | 98.1% |
| Ramshot Hunter | <<locked>> | 92% | 55,854 psi | 86% | 2959 fps | 99.9% |
| Ramshot Magnumᴾ | <<locked>> | 100% | 49,124 psi | 76% | 2881 fps | 98.5% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 37,086 psi | 57% | 1841 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 84% | 55,738 psi | 86% | 2884 fps | 99.8% |
| ReloadSwiss RS 60 | <<locked>> | 86% | 56,695 psi | 87% | 2989 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 92% | 58,581 psi | 90% | 2995 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 92% | 57,072 psi | 88% | 3028 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 45,136 psi | 69% | 2904 fps | 98.7% |
| Rottweil R 902 | <<locked>> | 84% | 58,755 psi | 90% | 2874 fps | 100% |
| Rottweil R 903 | <<locked>> | 86% | 55,376 psi | 85% | 2871 fps | 100% |
| Rottweil R 904 | <<locked>> | 96% | 57,406 psi | 88% | 2936 fps | 98.1% |
| Rottweil R 905 | <<locked>> | 98% | 58,407 psi | 90% | 2999 fps | 99.2% |
| Rottweil R 907 | <<locked>> | 90% | 58,392 psi | 90% | 2923 fps | 99.5% |
| Shooters World Long Rifle | <<locked>> | 90% | 56,579 psi | 87% | 2890 fps | 100% |
| Shooters World Precision | <<locked>> | 84% | 56,971 psi | 88% | 2864 fps | 100% |
| Shooters World SW4350 | <<locked>> | 92% | 58,175 psi | 89% | 2936 fps | 99.8% |
| SNPE Vectan SP 11 | <<locked>> | 86% | 57,450 psi | 88% | 2936 fps | 100% |
| SNPE Vectan SP 9 | <<locked>> | 82% | 58,088 psi | 89% | 2904 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 86% | 56,391 psi | 87% | 2753 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 90% | 56,115 psi | 86% | 2841 fps | 99.6% |
| SNPE Vectan Tubal 8000 | <<locked>> | 98% | 57,914 psi | 89% | 2995 fps | 99.1% |
| Somchem S335 | <<locked>> | 82% | 58,378 psi | 90% | 2792 fps | 100% |
| Somchem S355 | <<locked>> | 86% | 55,535 psi | 85% | 2871 fps | 100% |
| Somchem S361 | <<locked>> | 94% | 55,405 psi | 85% | 2871 fps | 97% |
| Somchem S365 | <<locked>> | 94% | 56,753 psi | 87% | 2956 fps | 100% |
| Somchem S385 | <<locked>> | 96% | 54,940 psi | 85% | 2913 fps | 99.3% |
| Vihtavuori N135 | <<locked>> | 82% | 55,912 psi | 86% | 2782 fps | 100% |
| Vihtavuori N140 | <<locked>> | 82% | 56,057 psi | 86% | 2799 fps | 100% |
| Vihtavuori N150 | <<locked>> | 88% | 56,942 psi | 88% | 2844 fps | 100% |
| Vihtavuori N160 | <<locked>> | 90% | 55,506 psi | 85% | 2897 fps | 100% |
| Vihtavuori N165ᴾ | <<locked>> | 100% | 54,505 psi | 84% | 2890 fps | 99% |
| Vihtavuori N540 | <<locked>> | 84% | 57,682 psi | 89% | 2841 fps | 100% |
| Vihtavuori N550 | <<locked>> | 92% | 58,276 psi | 90% | 2953 fps | 100% |
| Vihtavuori N555 | <<locked>> | 98% | 55,593 psi | 86% | 2963 fps | 100% |
| Vihtavuori N560 | <<locked>> | 98% | 56,376 psi | 87% | 3035 fps | 97.6% |
| Vihtavuori N565ᴾ | <<locked>> | 100% | 48,022 psi | 74% | 2877 fps | 96.1% |
| Winchester 6.5 StaBALL | <<locked>> | 90% | 55,245 psi | 85% | 2861 fps | 100% |
| Winchester 760 | <<locked>> | 90% | 57,319 psi | 88% | 2979 fps | 99.7% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 48,950 psi | 75% | 3009 fps | 100% |
| Winchester StaBALL Match | <<locked>> | 82% | 58,378 psi | 90% | 2913 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 98% | 55,201 psi | 85% | 2910 fps | 98.6% |
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 2495 | <<locked>> | 80% | 52,808 psi | 81% | 2743 fps | 100% |
| Accurate 2700 | <<locked>> | 80% | 50,894 psi | 78% | 2769 fps | 98.6% |
| Accurate 3100 | <<locked>> | 84% | 32,329 psi | 50% | 2467 fps | 95.4% |
| Accurate 4064 | <<locked>> | 80% | 50,096 psi | 77% | 2753 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 38,493 psi | 59% | 2628 fps | 98.9% |
| Accurate MAGPRO | <<locked>> | 96% | 51,082 psi | 79% | 2949 fps | 95.9% |
| ADI AR 2208 | <<locked>> | 80% | 47,456 psi | 73% | 2736 fps | 100% |
| ADI AR 2209 | <<locked>> | 86% | 39,914 psi | 61% | 2667 fps | 95% |
| ADI AR 2213 | <<locked>> | 94% | 46,760 psi | 72% | 2838 fps | 95.7% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 53,040 psi | 82% | 2956 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 86% | 40,118 psi | 62% | 2671 fps | 95.2% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 48,167 psi | 74% | 2759 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 80% | 51,372 psi | 79% | 2828 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 80% | 37,565 psi | 58% | 2641 fps | 99% |
| Alliant Reloder-17 | <<locked>> | 80% | 42,757 psi | 66% | 2766 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 86% | 39,697 psi | 61% | 2664 fps | 95.1% |
| Alliant Reloder-22 | <<locked>> | 90% | 39,943 psi | 61% | 2713 fps | 95.4% |
| Alliant Reloder-23 | <<locked>> | 80% | 27,311 psi | 42% | 2388 fps | 96.9% |
| Alliant Reloder-25 | <<locked>> | 88% | 31,140 psi | 48% | 2513 fps | 95.3% |
| Alliant Reloder-26 | 53.6 gr | 80% | 29,182 psi | 45% | 2497 fps | 95.2% |
| Bofors RP15 | <<locked>> | 92% | 39,639 psi | 61% | 2703 fps | 95.1% |
| Bofors RP3 | <<locked>> | 80% | 48,327 psi | 74% | 2766 fps | 100% |
| Bofors RP5 | <<locked>> | 90% | 39,943 psi | 61% | 2713 fps | 95.4% |
| Bofors RP7 | <<locked>> | 80% | 42,525 psi | 65% | 2648 fps | 97.1% |
| Hodgdon H1000 | <<locked>> | 98% | 42,656 psi | 66% | 2746 fps | 95.3% |
| Hodgdon H380 | <<locked>> | 80% | 48,863 psi | 75% | 2785 fps | 99.8% |
| Hodgdon H414 | <<locked>> | 80% | 40,625 psi | 63% | 2680 fps | 97.2% |
| Hodgdon H4350 | <<locked>> | 80% | 43,497 psi | 67% | 2700 fps | 96.6% |
| Hodgdon H4831 | <<locked>> | 92% | 46,775 psi | 72% | 2785 fps | 95% |
| Hodgdon H4831 SC | <<locked>> | 94% | 49,095 psi | 76% | 2828 fps | 95.7% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 35,114 psi | 54% | 2533 fps | 99.4% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 53,490 psi | 82% | 2874 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 96% | 39,523 psi | 61% | 2776 fps | 95.7% |
| Hodgdon Superformance | <<locked>> | 80% | 39,552 psi | 61% | 2690 fps | 96.5% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,180 psi | 42% | 1608 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 54,070 psi | 83% | 2838 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 49,937 psi | 77% | 2769 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 80% | 52,301 psi | 80% | 2805 fps | 99.2% |
| IMR 4350 | <<locked>> | 80% | 38,116 psi | 59% | 2572 fps | 95.8% |
| IMR 4451 Enduron | <<locked>> | 80% | 44,005 psi | 68% | 2677 fps | 97.8% |
| IMR 4831 | <<locked>> | 80% | 37,057 psi | 57% | 2582 fps | 98.6% |
| IMR 4895 | <<locked>> | 80% | 52,736 psi | 81% | 2858 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 92% | 48,675 psi | 75% | 2782 fps | 95.8% |
| IMR 7828 SSC | <<locked>> | 94% | 44,570 psi | 69% | 2808 fps | 95.2% |
| Lovex S060 | <<locked>> | 80% | 54,563 psi | 84% | 2805 fps | 100% |
| Lovex S062 | <<locked>> | 80% | 50,053 psi | 77% | 2762 fps | 100% |
| Lovex S065 | <<locked>> | 80% | 41,336 psi | 64% | 2625 fps | 98.4% |
| Lovex S070 | <<locked>> | 80% | 39,465 psi | 61% | 2602 fps | 97% |
| Lovex S071 | <<locked>> | 88% | 31,430 psi | 48% | 2444 fps | 95% |
| Norma 201 | <<locked>> | 80% | 54,462 psi | 84% | 2822 fps | 100% |
| Norma 203B | <<locked>> | 80% | 50,749 psi | 78% | 2815 fps | 100% |
| Norma 204 | <<locked>> | 82% | 40,350 psi | 62% | 2657 fps | 95.1% |
| Norma MRP | 56 gr | 86% | 36,593 psi | 56% | 2664 fps | 95.7% |
| Norma URP | <<locked>> | 80% | 38,218 psi | 59% | 2621 fps | 98.7% |
| Ramshot Big Game | <<locked>> | 80% | 51,213 psi | 79% | 2838 fps | 100% |
| Ramshot Grand | <<locked>> | 94% | 44,411 psi | 68% | 2818 fps | 95.5% |
| Ramshot Hunter | <<locked>> | 80% | 37,188 psi | 57% | 2608 fps | 97% |
| Ramshot Magnum | <<locked>> | 94% | 39,363 psi | 61% | 2687 fps | 96% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,630 psi | 43% | 1647 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 48,805 psi | 75% | 2769 fps | 99.2% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 45,469 psi | 70% | 2815 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 38,450 psi | 59% | 2648 fps | 98.6% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 37,101 psi | 57% | 2654 fps | 98.1% |
| ReloadSwiss RS 76 | <<locked>> | 94% | 36,376 psi | 56% | 2694 fps | 95.6% |
| Rottweil R 902 | <<locked>> | 80% | 51,866 psi | 80% | 2772 fps | 100% |
| Rottweil R 903 | <<locked>> | 80% | 45,426 psi | 70% | 2713 fps | 100% |
| Rottweil R 904 | <<locked>> | 88% | 44,338 psi | 68% | 2710 fps | 95.2% |
| Rottweil R 905 | <<locked>> | 86% | 38,740 psi | 60% | 2644 fps | 95% |
| Rottweil R 907 | <<locked>> | 80% | 42,525 psi | 65% | 2648 fps | 97.1% |
| Shooters World Long Rifle | <<locked>> | 80% | 41,336 psi | 64% | 2625 fps | 98.4% |
| Shooters World Precision | <<locked>> | 80% | 50,053 psi | 77% | 2762 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 39,465 psi | 61% | 2602 fps | 97% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 46,905 psi | 72% | 2772 fps | 100% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 54,404 psi | 84% | 2851 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 46,847 psi | 72% | 2618 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 40,480 psi | 62% | 2569 fps | 97.2% |
| SNPE Vectan Tubal 8000 | <<locked>> | 88% | 41,263 psi | 63% | 2700 fps | 95.8% |
| Somchem S335 | <<locked>> | 80% | 54,969 psi | 85% | 2749 fps | 100% |
| Somchem S355 | <<locked>> | 80% | 45,803 psi | 70% | 2713 fps | 100% |
| Somchem S361 | <<locked>> | 90% | 48,559 psi | 75% | 2759 fps | 95.5% |
| Somchem S365 | <<locked>> | 80% | 34,780 psi | 54% | 2579 fps | 99.9% |
| Somchem S385 | <<locked>> | 84% | 36,898 psi | 57% | 2575 fps | 95.3% |
| Vihtavuori N135 | <<locked>> | 80% | 52,417 psi | 81% | 2736 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 52,402 psi | 81% | 2746 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 43,671 psi | 67% | 2641 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 39,798 psi | 61% | 2625 fps | 99% |
| Vihtavuori N165 | <<locked>> | 90% | 38,798 psi | 60% | 2608 fps | 95.5% |
| Vihtavuori N540 | <<locked>> | 80% | 50,821 psi | 78% | 2746 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 39,218 psi | 60% | 2625 fps | 98.7% |
| Vihtavuori N555 | <<locked>> | 80% | 30,226 psi | 47% | 2464 fps | 97% |
| Vihtavuori N560 | 59.9 gr | 92% | 45,687 psi | 70% | 2844 fps | 95.1% |
| Vihtavuori N565 | <<locked>> | 98% | 44,715 psi | 69% | 2815 fps | 95.1% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 38,928 psi | 60% | 2592 fps | 99.9% |
| Winchester 760 | <<locked>> | 80% | 40,625 psi | 63% | 2680 fps | 97.2% |
| Winchester StaBALL HD | <<locked>> | 80% | 23,975 psi | 37% | 2352 fps | 95.4% |
| Winchester StaBALL Match | <<locked>> | 80% | 54,607 psi | 84% | 2861 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 90% | 41,553 psi | 64% | 2671 fps | 95.7% |
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 6.8 Western loaded with the .277 | 145gr | Fox Classic Hunter. Alliant Reloder-26 delivers the highest muzzle velocity at 3,087 fps; across all powders the maximum-charge window runs from 1,801 fps to 3,087 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 (448 MPa), the top charges use 56–90 %, leaving at least 10 % headroom. The 145.0 gr projectile in 0.277" calls for a 1:9.0 twist; slower twists will usually not stabilise this weight. Accurate 3100, ADI AR 2213, Alliant Reloder-22 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-26, Norma MRP, Vihtavuori N560 rank at the top here: for 6.8 Western with the .277 | 145gr | 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.