Load Specifications
Load data in caliber 6.5 PRC with .264 | 123gr | Hornady SST 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-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% | 57,276 psi | 88% | 2881 fps | 100% |
| Accurate 2700 | <<locked>> | 84% | 58,421 psi | 90% | 2963 fps | 99.2% |
| Accurate 3100ᴾ | <<locked>> | 100% | 57,130 psi | 88% | 3009 fps | 99.9% |
| Accurate 4064 | <<locked>> | 84% | 57,653 psi | 89% | 2936 fps | 100% |
| Accurate 4350 | <<locked>> | 90% | 55,085 psi | 85% | 2999 fps | 100% |
| Accurate MAGPRO | <<locked>> | 98% | 55,477 psi | 85% | 3097 fps | 96.3% |
| ADI AR 2208 | <<locked>> | 86% | 57,566 psi | 89% | 2976 fps | 100% |
| ADI AR 2209 | <<locked>> | 96% | 56,130 psi | 86% | 3048 fps | 98.5% |
| ADI AR 2213ᴾ | <<locked>> | 100% | 57,522 psi | 89% | 3104 fps | 97.7% |
| Alliant Power Pro 2000-MR | <<locked>> | 82% | 57,276 psi | 88% | 3104 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 96% | 56,289 psi | 87% | 3045 fps | 98.5% |
| Alliant Reloder- TS 15.5 | <<locked>> | 86% | 58,479 psi | 90% | 2999 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 82% | 55,042 psi | 85% | 2966 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 92% | 55,883 psi | 86% | 3058 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 88% | 57,130 psi | 88% | 3077 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 96% | 55,506 psi | 85% | 3035 fps | 98.4% |
| Alliant Reloder-22ᴾ | <<locked>> | 100% | 56,637 psi | 87% | 3097 fps | 98.7% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 53,505 psi | 82% | 3022 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 46,325 psi | 71% | 2946 fps | 99.5% |
| Alliant Reloder-26 | <<locked>> | 98% | 57,798 psi | 89% | 3169 fps | 100% |
| Bofors RP15ᴾ | <<locked>> | 100% | 51,706 psi | 80% | 3015 fps | 97.8% |
| Bofors RP3 | <<locked>> | 84% | 55,883 psi | 86% | 2963 fps | 100% |
| Bofors RP5ᴾ | <<locked>> | 100% | 56,637 psi | 87% | 3097 fps | 98.7% |
| Bofors RP7 | <<locked>> | 90% | 58,784 psi | 90% | 3005 fps | 99.4% |
| Hodgdon H380 | <<locked>> | 84% | 56,115 psi | 86% | 2979 fps | 100% |
| Hodgdon H414 | <<locked>> | 90% | 57,334 psi | 88% | 3058 fps | 99.6% |
| Hodgdon H4350 | <<locked>> | 88% | 56,652 psi | 87% | 3012 fps | 98.8% |
| Hodgdon H4831 | <<locked>> | 98% | 57,653 psi | 89% | 3045 fps | 97% |
| Hodgdon H4831 SC | <<locked>> | 98% | 56,275 psi | 87% | 3022 fps | 96.8% |
| Hodgdon Hybrid 100V | <<locked>> | 94% | 56,057 psi | 86% | 2976 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 82% | 57,435 psi | 88% | 3015 fps | 100% |
| Hodgdon Retumboᴾ | <<locked>> | 100% | 45,527 psi | 70% | 2986 fps | 97.3% |
| Hodgdon Superformance | <<locked>> | 90% | 57,682 psi | 89% | 3094 fps | 99.5% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,651 psi | 56% | 1864 fps | 100% |
| Hodgdon VARGET | <<locked>> | 82% | 57,986 psi | 89% | 2979 fps | 100% |
| IMR 4064 | <<locked>> | 84% | 56,753 psi | 87% | 2953 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 82% | 55,956 psi | 86% | 2940 fps | 99.4% |
| IMR 4350 | <<locked>> | 92% | 56,333 psi | 87% | 2982 fps | 99.2% |
| IMR 4451 Enduron | <<locked>> | 88% | 56,797 psi | 87% | 2979 fps | 99.4% |
| IMR 4831 | <<locked>> | 92% | 55,492 psi | 85% | 2992 fps | 100% |
| IMR 4895 | <<locked>> | 82% | 56,463 psi | 87% | 2992 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 96% | 55,448 psi | 85% | 2972 fps | 96.8% |
| IMR 7828 SSCᴾ | <<locked>> | 100% | 54,824 psi | 84% | 3071 fps | 97.3% |
| Lovex S060 | <<locked>> | 82% | 58,131 psi | 89% | 2936 fps | 100% |
| Lovex S062 | <<locked>> | 84% | 57,043 psi | 88% | 2946 fps | 100% |
| Lovex S065 | <<locked>> | 90% | 56,956 psi | 88% | 2972 fps | 99.9% |
| Lovex S070 | <<locked>> | 92% | 58,450 psi | 90% | 3018 fps | 99.7% |
| Lovex S071ᴾ | <<locked>> | 100% | 47,195 psi | 73% | 2851 fps | 98.9% |
| Norma 201 | <<locked>> | 82% | 58,494 psi | 90% | 2959 fps | 100% |
| Norma 203B | <<locked>> | 84% | 58,088 psi | 89% | 3009 fps | 100% |
| Norma 204 | <<locked>> | 92% | 57,203 psi | 88% | 3038 fps | 98.5% |
| Norma MRP | <<locked>> | 98% | 56,478 psi | 87% | 3127 fps | 99.6% |
| Norma URP | <<locked>> | 92% | 57,421 psi | 88% | 3038 fps | 100% |
| Ramshot Big Game | <<locked>> | 82% | 55,230 psi | 85% | 2979 fps | 100% |
| Ramshot Grandᴾ | <<locked>> | 100% | 55,535 psi | 85% | 3094 fps | 97.8% |
| Ramshot Hunter | <<locked>> | 92% | 56,231 psi | 87% | 3041 fps | 99.8% |
| Ramshot Magnumᴾ | <<locked>> | 100% | 49,400 psi | 76% | 2956 fps | 98.2% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 37,159 psi | 57% | 1903 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 84% | 55,956 psi | 86% | 2963 fps | 99.7% |
| ReloadSwiss RS 60 | <<locked>> | 86% | 56,579 psi | 87% | 3071 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 90% | 55,056 psi | 85% | 3022 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 92% | 57,276 psi | 88% | 3110 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 45,484 psi | 70% | 2979 fps | 98.3% |
| Rottweil R 902 | <<locked>> | 82% | 55,564 psi | 86% | 2907 fps | 100% |
| Rottweil R 903 | <<locked>> | 86% | 56,086 psi | 86% | 2959 fps | 100% |
| Rottweil R 904 | <<locked>> | 96% | 57,711 psi | 89% | 3018 fps | 97.7% |
| Rottweil R 905 | <<locked>> | 98% | 58,508 psi | 90% | 3077 fps | 98.9% |
| Rottweil R 907 | <<locked>> | 90% | 58,784 psi | 90% | 3005 fps | 99.4% |
| Shooters World Long Rifle | <<locked>> | 90% | 56,956 psi | 88% | 2972 fps | 99.9% |
| Shooters World Precision | <<locked>> | 84% | 57,043 psi | 88% | 2946 fps | 100% |
| Shooters World SW4350 | <<locked>> | 92% | 58,450 psi | 90% | 3018 fps | 99.7% |
| SNPE Vectan SP 11 | <<locked>> | 86% | 57,522 psi | 89% | 3018 fps | 100% |
| SNPE Vectan SP 9 | <<locked>> | 82% | 58,160 psi | 90% | 2986 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 86% | 56,565 psi | 87% | 2835 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 90% | 56,536 psi | 87% | 2923 fps | 99.4% |
| SNPE Vectan Tubal 8000 | <<locked>> | 98% | 58,044 psi | 89% | 3077 fps | 98.9% |
| Somchem S335 | <<locked>> | 82% | 58,798 psi | 90% | 2877 fps | 100% |
| Somchem S355 | <<locked>> | 86% | 55,738 psi | 86% | 2953 fps | 100% |
| Somchem S361 | <<locked>> | 94% | 55,738 psi | 86% | 2949 fps | 96.6% |
| Somchem S365 | <<locked>> | 94% | 56,956 psi | 88% | 3038 fps | 100% |
| Somchem S385 | <<locked>> | 96% | 55,477 psi | 85% | 2999 fps | 99.1% |
| Vihtavuori N135 | <<locked>> | 82% | 56,275 psi | 87% | 2867 fps | 100% |
| Vihtavuori N140 | <<locked>> | 82% | 56,246 psi | 87% | 2881 fps | 100% |
| Vihtavuori N150 | <<locked>> | 88% | 57,130 psi | 88% | 2927 fps | 100% |
| Vihtavuori N160 | <<locked>> | 90% | 55,767 psi | 86% | 2976 fps | 100% |
| Vihtavuori N165ᴾ | <<locked>> | 100% | 54,810 psi | 84% | 2972 fps | 98.7% |
| Vihtavuori N540 | <<locked>> | 84% | 57,986 psi | 89% | 2927 fps | 100% |
| Vihtavuori N550 | <<locked>> | 92% | 58,566 psi | 90% | 3038 fps | 100% |
| Vihtavuori N555 | <<locked>> | 98% | 56,043 psi | 86% | 3048 fps | 100% |
| Vihtavuori N560 | <<locked>> | 98% | 56,579 psi | 87% | 3114 fps | 97.2% |
| Winchester 6.5 StaBALL | <<locked>> | 90% | 55,259 psi | 85% | 2940 fps | 100% |
| Winchester 760 | <<locked>> | 90% | 57,334 psi | 88% | 3058 fps | 99.6% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 48,994 psi | 75% | 3087 fps | 100% |
| Winchester StaBALL Match | <<locked>> | 82% | 58,755 psi | 90% | 2999 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 98% | 55,477 psi | 85% | 2989 fps | 98.3% |
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% | 53,795 psi | 83% | 2835 fps | 100% |
| Accurate 2700 | <<locked>> | 80% | 51,227 psi | 79% | 2848 fps | 98.3% |
| Accurate 3100 | <<locked>> | 84% | 33,083 psi | 51% | 2549 fps | 95.1% |
| Accurate 4064 | <<locked>> | 80% | 51,010 psi | 79% | 2841 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 39,160 psi | 60% | 2710 fps | 98.6% |
| Accurate MAGPRO | <<locked>> | 96% | 51,401 psi | 79% | 3025 fps | 95.4% |
| ADI AR 2208 | <<locked>> | 80% | 47,718 psi | 73% | 2815 fps | 99.9% |
| ADI AR 2209 | <<locked>> | 88% | 43,091 psi | 66% | 2805 fps | 95.5% |
| ADI AR 2213 | <<locked>> | 94% | 46,949 psi | 72% | 2910 fps | 95.1% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 53,417 psi | 82% | 3045 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 88% | 43,366 psi | 67% | 2808 fps | 95.7% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 48,414 psi | 75% | 2841 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 80% | 51,793 psi | 80% | 2913 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 80% | 37,942 psi | 58% | 2720 fps | 98.7% |
| Alliant Reloder-17 | <<locked>> | 80% | 43,091 psi | 66% | 2844 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 88% | 42,873 psi | 66% | 2799 fps | 95.6% |
| Alliant Reloder-22 | <<locked>> | 92% | 43,120 psi | 66% | 2848 fps | 95.9% |
| Alliant Reloder-23 | <<locked>> | 80% | 27,934 psi | 43% | 2464 fps | 96.6% |
| Alliant Reloder-25 | <<locked>> | 90% | 33,649 psi | 52% | 2644 fps | 95.9% |
| Alliant Reloder-26 | 50.6 gr | 82% | 31,952 psi | 49% | 2638 fps | 96% |
| Bofors RP15 | <<locked>> | 94% | 42,540 psi | 65% | 2835 fps | 95.5% |
| Bofors RP3 | <<locked>> | 80% | 49,052 psi | 75% | 2858 fps | 100% |
| Bofors RP5 | <<locked>> | 92% | 43,120 psi | 66% | 2848 fps | 95.9% |
| Bofors RP7 | <<locked>> | 80% | 42,830 psi | 66% | 2720 fps | 96.7% |
| Hodgdon H380 | <<locked>> | 80% | 49,298 psi | 76% | 2867 fps | 99.7% |
| Hodgdon H414 | <<locked>> | 80% | 41,075 psi | 63% | 2756 fps | 96.8% |
| Hodgdon H4350 | <<locked>> | 80% | 43,918 psi | 68% | 2779 fps | 96.2% |
| Hodgdon H4831 | <<locked>> | 94% | 50,140 psi | 77% | 2917 fps | 95.4% |
| Hodgdon H4831 SC | <<locked>> | 94% | 49,240 psi | 76% | 2900 fps | 95.1% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 35,534 psi | 55% | 2608 fps | 99.2% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 53,693 psi | 83% | 2959 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 96% | 40,001 psi | 62% | 2851 fps | 95.1% |
| Hodgdon Superformance | <<locked>> | 80% | 40,045 psi | 62% | 2766 fps | 96.1% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,354 psi | 42% | 1663 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 54,273 psi | 84% | 2923 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 50,198 psi | 77% | 2848 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 80% | 52,431 psi | 81% | 2881 fps | 99% |
| IMR 4350 | <<locked>> | 80% | 38,464 psi | 59% | 2644 fps | 95.3% |
| IMR 4451 Enduron | <<locked>> | 80% | 44,222 psi | 68% | 2753 fps | 97.5% |
| IMR 4831 | <<locked>> | 80% | 37,594 psi | 58% | 2661 fps | 98.4% |
| IMR 4895 | <<locked>> | 80% | 53,142 psi | 82% | 2943 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 92% | 48,921 psi | 75% | 2858 fps | 95.3% |
| IMR 7828 SSC | <<locked>> | 96% | 47,921 psi | 74% | 2943 fps | 95.6% |
| Lovex S060 | <<locked>> | 80% | 54,766 psi | 84% | 2887 fps | 100% |
| Lovex S062 | <<locked>> | 80% | 50,502 psi | 78% | 2844 fps | 100% |
| Lovex S065 | <<locked>> | 80% | 41,901 psi | 64% | 2703 fps | 98.2% |
| Lovex S070 | <<locked>> | 80% | 40,161 psi | 62% | 2684 fps | 96.7% |
| Lovex S071 | <<locked>> | 90% | 34,316 psi | 53% | 2579 fps | 95.6% |
| Norma 201 | <<locked>> | 80% | 55,042 psi | 85% | 2907 fps | 100% |
| Norma 203B | <<locked>> | 80% | 51,155 psi | 79% | 2900 fps | 100% |
| Norma 204 | <<locked>> | 84% | 43,453 psi | 67% | 2792 fps | 95.5% |
| Norma MRP | 51.6 gr | 86% | 37,072 psi | 57% | 2740 fps | 95.3% |
| Norma URP | <<locked>> | 80% | 38,856 psi | 60% | 2703 fps | 98.5% |
| Ramshot Big Game | <<locked>> | 80% | 51,663 psi | 80% | 2923 fps | 100% |
| Ramshot Grand | <<locked>> | 96% | 48,008 psi | 74% | 2956 fps | 96% |
| Ramshot Hunter | <<locked>> | 80% | 37,666 psi | 58% | 2687 fps | 96.7% |
| Ramshot Magnum | <<locked>> | 94% | 39,740 psi | 61% | 2759 fps | 95.5% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,876 psi | 43% | 1706 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 49,081 psi | 76% | 2848 fps | 98.9% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 45,745 psi | 70% | 2900 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 38,943 psi | 60% | 2726 fps | 98.4% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 37,666 psi | 58% | 2733 fps | 97.8% |
| ReloadSwiss RS 76 | <<locked>> | 94% | 36,796 psi | 57% | 2762 fps | 95% |
| Rottweil R 902 | <<locked>> | 80% | 52,301 psi | 80% | 2858 fps | 100% |
| Rottweil R 903 | <<locked>> | 80% | 46,151 psi | 71% | 2799 fps | 100% |
| Rottweil R 904 | <<locked>> | 90% | 47,645 psi | 73% | 2841 fps | 95.6% |
| Rottweil R 905 | <<locked>> | 88% | 41,974 psi | 65% | 2782 fps | 95.5% |
| Rottweil R 907 | <<locked>> | 80% | 42,830 psi | 66% | 2720 fps | 96.7% |
| Shooters World Long Rifle | <<locked>> | 80% | 41,901 psi | 64% | 2703 fps | 98.2% |
| Shooters World Precision | <<locked>> | 80% | 50,502 psi | 78% | 2844 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 40,161 psi | 62% | 2684 fps | 96.7% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 47,355 psi | 73% | 2854 fps | 100% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 54,795 psi | 84% | 2936 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 47,181 psi | 73% | 2700 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 40,988 psi | 63% | 2644 fps | 96.8% |
| SNPE Vectan Tubal 8000 | <<locked>> | 88% | 41,582 psi | 64% | 2776 fps | 95.4% |
| Somchem S335 | <<locked>> | 80% | 55,448 psi | 85% | 2831 fps | 100% |
| Somchem S355 | <<locked>> | 80% | 46,383 psi | 71% | 2799 fps | 100% |
| Somchem S361 | <<locked>> | 90% | 48,863 psi | 75% | 2831 fps | 95% |
| Somchem S365 | <<locked>> | 80% | 35,230 psi | 54% | 2654 fps | 99.8% |
| Somchem S385 | <<locked>> | 86% | 39,769 psi | 61% | 2703 fps | 95.7% |
| Vihtavuori N135 | <<locked>> | 80% | 52,794 psi | 81% | 2822 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 52,939 psi | 81% | 2831 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 44,309 psi | 68% | 2723 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 40,248 psi | 62% | 2703 fps | 98.8% |
| Vihtavuori N165 | <<locked>> | 90% | 39,204 psi | 60% | 2684 fps | 95.1% |
| Vihtavuori N540 | <<locked>> | 80% | 51,198 psi | 79% | 2828 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 39,711 psi | 61% | 2703 fps | 98.5% |
| Vihtavuori N555 | <<locked>> | 80% | 30,951 psi | 48% | 2543 fps | 96.8% |
| Vihtavuori N560 | 56.4 gr | 94% | 49,327 psi | 76% | 2986 fps | 95.5% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 39,305 psi | 60% | 2667 fps | 99.8% |
| Winchester 760 | <<locked>> | 80% | 41,075 psi | 63% | 2756 fps | 96.8% |
| Winchester StaBALL HD | <<locked>> | 80% | 24,700 psi | 38% | 2431 fps | 95.2% |
| Winchester StaBALL Match | <<locked>> | 80% | 54,998 psi | 85% | 2946 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 90% | 41,959 psi | 65% | 2746 fps | 95.3% |
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 6.5 PRC loaded with the .264 | 123gr | Hornady SST. Alliant Reloder-26 delivers the highest muzzle velocity at 3,169 fps; across all powders the maximum-charge window runs from 1,864 fps to 3,169 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 (448 MPa), the top charges use 56–90 %, leaving at least 10 % headroom. The 123.0 gr projectile in 0.264" 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 6.5 PRC with the .264 | 123gr | Hornady SST 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.