Load Specifications
Load data in caliber .260 Ackley Improved with .264 | 122gr | THAC EDH 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 60, Alliant Reloder-17 and Alliant Power Pro 2000-MR.
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>> | 84% | 55,027 psi | 88% | 2717 fps | 100% |
| Accurate 2495 | <<locked>> | 88% | 53,911 psi | 86% | 2743 fps | 100% |
| Accurate 2520 | <<locked>> | 84% | 54,998 psi | 88% | 2802 fps | 100% |
| Accurate 2700 | <<locked>> | 90% | 55,854 psi | 90% | 2776 fps | 96.6% |
| Accurate 4064 | <<locked>> | 90% | 53,940 psi | 86% | 2789 fps | 100% |
| Accurate 4350ᴾ | <<locked>> | 100% | 56,101 psi | 90% | 2907 fps | 99.5% |
| ADI AR 2206H | <<locked>> | 86% | 53,635 psi | 86% | 2808 fps | 99.8% |
| ADI AR 2208 | <<locked>> | 92% | 54,346 psi | 87% | 2805 fps | 99.6% |
| ADI Benchmark 8208 | <<locked>> | 86% | 55,898 psi | 90% | 2808 fps | 100% |
| Alliant AR-Comp | <<locked>> | 84% | 53,447 psi | 86% | 2743 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 90% | 56,188 psi | 90% | 2972 fps | 99.8% |
| Alliant Reloder- TS 15.5 | <<locked>> | 92% | 54,346 psi | 87% | 2828 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 90% | 54,998 psi | 88% | 2851 fps | 99.7% |
| Alliant Reloder-16ᴾ | <<locked>> | 100% | 53,664 psi | 86% | 2907 fps | 99.5% |
| Alliant Reloder-17 | <<locked>> | 96% | 54,737 psi | 88% | 2946 fps | 100% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 38,928 psi | 62% | 2651 fps | 98.2% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 42,946 psi | 69% | 2799 fps | 97.2% |
| Baschieri & Pellagri 107 | <<locked>> | 86% | 53,040 psi | 85% | 2818 fps | 99.3% |
| Bofors RP3 | <<locked>> | 92% | 55,230 psi | 89% | 2848 fps | 100% |
| Bofors RP7 | <<locked>> | 96% | 55,100 psi | 88% | 2805 fps | 96.7% |
| Hodgdon Benchmark | <<locked>> | 84% | 54,491 psi | 87% | 2746 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 86% | 55,376 psi | 89% | 2841 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 82% | 53,490 psi | 86% | 2884 fps | 99.6% |
| Hodgdon H322 | <<locked>> | 82% | 56,376 psi | 90% | 2799 fps | 100% |
| Hodgdon H380 | <<locked>> | 92% | 55,985 psi | 90% | 2854 fps | 99.2% |
| Hodgdon H414 | <<locked>> | 98% | 54,926 psi | 88% | 2897 fps | 97.5% |
| Hodgdon H4350 | <<locked>> | 96% | 55,782 psi | 89% | 2858 fps | 96.2% |
| Hodgdon H4895 | <<locked>> | 86% | 54,201 psi | 87% | 2822 fps | 100% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 49,922 psi | 80% | 2785 fps | 99.8% |
| Hodgdon LEVERevolution | <<locked>> | 88% | 52,924 psi | 85% | 2848 fps | 100% |
| Hodgdon Superformance | <<locked>> | 98% | 55,840 psi | 90% | 2933 fps | 97.1% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 35,810 psi | 57% | 1719 fps | 100% |
| Hodgdon VARGET | <<locked>> | 88% | 54,984 psi | 88% | 2815 fps | 100% |
| IMR 3031 | <<locked>> | 86% | 54,157 psi | 87% | 2808 fps | 100% |
| IMR 4064 | <<locked>> | 90% | 54,085 psi | 87% | 2789 fps | 99.7% |
| IMR 4166 Enduron | <<locked>> | 88% | 53,998 psi | 87% | 2762 fps | 97.1% |
| IMR 4350ᴾ | <<locked>> | 100% | 55,100 psi | 88% | 2831 fps | 96.8% |
| IMR 4451 Enduron | <<locked>> | 94% | 53,417 psi | 86% | 2785 fps | 96.9% |
| IMR 4831ᴾ | <<locked>> | 100% | 52,808 psi | 85% | 2841 fps | 99.2% |
| IMR 4895 | <<locked>> | 90% | 56,376 psi | 90% | 2881 fps | 99.9% |
| IMR 8208 XBR | <<locked>> | 86% | 55,898 psi | 90% | 2808 fps | 100% |
| Lovex D073.6 | <<locked>> | 86% | 53,359 psi | 86% | 2789 fps | 100% |
| Lovex S060 | <<locked>> | 88% | 56,318 psi | 90% | 2782 fps | 99.9% |
| Lovex S062 | <<locked>> | 90% | 54,201 psi | 87% | 2792 fps | 100% |
| Lovex S065 | <<locked>> | 98% | 56,246 psi | 90% | 2831 fps | 98.6% |
| Lovex S070 | <<locked>> | 98% | 53,954 psi | 87% | 2818 fps | 97.4% |
| Norma 201 | <<locked>> | 88% | 55,941 psi | 90% | 2805 fps | 100% |
| Norma 202 | <<locked>> | 88% | 56,130 psi | 90% | 2805 fps | 100% |
| Norma 203B | <<locked>> | 90% | 54,201 psi | 87% | 2838 fps | 99.8% |
| Norma URPᴾ | <<locked>> | 100% | 54,650 psi | 88% | 2890 fps | 99.3% |
| Ramshot Big Game | <<locked>> | 90% | 54,288 psi | 87% | 2858 fps | 99.8% |
| Ramshot Hunterᴾ | <<locked>> | 100% | 53,606 psi | 86% | 2884 fps | 98% |
| Ramshot TAC | <<locked>> | 86% | 56,289 psi | 90% | 2828 fps | 98.8% |
| Ramshot Wild Boar | <<locked>> | 86% | 55,651 psi | 89% | 2844 fps | 99.9% |
| Ramshot X-Terminator | <<locked>> | 82% | 53,635 psi | 86% | 2762 fps | 99.7% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 36,071 psi | 58% | 1755 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 82% | 55,579 psi | 89% | 2792 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 92% | 56,434 psi | 90% | 2838 fps | 98.1% |
| ReloadSwiss RS 52 | <<locked>> | 88% | 55,288 psi | 89% | 2917 fps | 99.7% |
| ReloadSwiss RS 60 | <<locked>> | 94% | 54,476 psi | 87% | 2946 fps | 100% |
| ReloadSwiss RS 62ᴾ | <<locked>> | 100% | 55,622 psi | 89% | 2930 fps | 99.3% |
| ReloadSwiss RS 70ᴾ | <<locked>> | 100% | 55,245 psi | 89% | 2949 fps | 99.1% |
| Rottweil R 901 | <<locked>> | 84% | 54,143 psi | 87% | 2746 fps | 100% |
| Rottweil R 902 | <<locked>> | 90% | 56,405 psi | 90% | 2802 fps | 100% |
| Rottweil R 903 | <<locked>> | 94% | 55,056 psi | 88% | 2838 fps | 100% |
| Rottweil R 907 | <<locked>> | 96% | 55,100 psi | 88% | 2805 fps | 96.7% |
| Shooters World Long Rifle | <<locked>> | 98% | 56,246 psi | 90% | 2831 fps | 98.6% |
| Shooters World Match Rifle | <<locked>> | 86% | 53,359 psi | 86% | 2789 fps | 100% |
| Shooters World Precision | <<locked>> | 90% | 54,201 psi | 87% | 2792 fps | 100% |
| Shooters World SW4350 | <<locked>> | 98% | 53,954 psi | 87% | 2818 fps | 97.4% |
| SNPE Vectan SP 11 | <<locked>> | 94% | 56,101 psi | 90% | 2894 fps | 99.9% |
| SNPE Vectan SP 7 | <<locked>> | 86% | 54,911 psi | 88% | 2805 fps | 99% |
| SNPE Vectan SP 9 | <<locked>> | 88% | 55,317 psi | 89% | 2831 fps | 99.9% |
| SNPE Vectan Tubal 3000 | <<locked>> | 86% | 54,114 psi | 87% | 2700 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 92% | 53,911 psi | 86% | 2697 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 96% | 53,476 psi | 86% | 2740 fps | 97% |
| Somchem S321 | <<locked>> | 82% | 53,954 psi | 87% | 2795 fps | 100% |
| Somchem S335 | <<locked>> | 86% | 53,635 psi | 86% | 2700 fps | 100% |
| Somchem S341 | <<locked>> | 86% | 54,128 psi | 87% | 2795 fps | 99.8% |
| Somchem S355 | <<locked>> | 94% | 55,463 psi | 89% | 2838 fps | 100% |
| Somchem S365ᴾ | <<locked>> | 100% | 49,385 psi | 79% | 2848 fps | 100% |
| Vihtavuori N130 | <<locked>> | 82% | 54,041 psi | 87% | 2664 fps | 100% |
| Vihtavuori N133 | <<locked>> | 86% | 54,172 psi | 87% | 2684 fps | 100% |
| Vihtavuori N135 | <<locked>> | 90% | 55,898 psi | 90% | 2766 fps | 100% |
| Vihtavuori N140 | <<locked>> | 88% | 53,200 psi | 85% | 2736 fps | 100% |
| Vihtavuori N150 | <<locked>> | 94% | 53,200 psi | 85% | 2766 fps | 100% |
| Vihtavuori N160 | <<locked>> | 98% | 53,708 psi | 86% | 2831 fps | 99.2% |
| Vihtavuori N530 | <<locked>> | 84% | 52,924 psi | 85% | 2759 fps | 100% |
| Vihtavuori N540 | <<locked>> | 90% | 55,085 psi | 88% | 2785 fps | 100% |
| Vihtavuori N550ᴾ | <<locked>> | 100% | 56,391 psi | 90% | 2890 fps | 99.3% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 42,322 psi | 68% | 2730 fps | 98.2% |
| Winchester 6.5 StaBALL | <<locked>> | 98% | 54,128 psi | 87% | 2815 fps | 100% |
| Winchester 748 | <<locked>> | 86% | 56,159 psi | 90% | 2854 fps | 100% |
| Winchester 760 | <<locked>> | 98% | 55,274 psi | 89% | 2904 fps | 97.6% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 34,983 psi | 56% | 2641 fps | 97.8% |
| Winchester StaBALL Match | <<locked>> | 88% | 55,085 psi | 88% | 2838 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% | 48,646 psi | 78% | 2625 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 42,351 psi | 68% | 2566 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 48,298 psi | 77% | 2700 fps | 100% |
| Accurate 2700 | <<locked>> | 86% | 49,240 psi | 79% | 2671 fps | 95.2% |
| Accurate 4064 | <<locked>> | 80% | 40,001 psi | 64% | 2562 fps | 100% |
| Accurate 4350 | <<locked>> | 86% | 35,433 psi | 57% | 2533 fps | 95.4% |
| ADI AR 2206H | <<locked>> | 80% | 44,686 psi | 72% | 2654 fps | 98.9% |
| ADI AR 2208 | <<locked>> | 80% | 38,101 psi | 61% | 2507 fps | 96.8% |
| ADI Benchmark 8208 | <<locked>> | 80% | 46,586 psi | 75% | 2661 fps | 99.7% |
| Alliant AR-Comp | <<locked>> | 80% | 46,862 psi | 75% | 2651 fps | 100% |
| Alliant Power Pro 2000-MR | 36.6 gr | 80% | 40,654 psi | 65% | 2684 fps | 97.4% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 38,014 psi | 61% | 2536 fps | 98.4% |
| Alliant Reloder-15 | <<locked>> | 80% | 40,553 psi | 65% | 2592 fps | 97.7% |
| Alliant Reloder-16 | <<locked>> | 86% | 35,346 psi | 57% | 2533 fps | 95.3% |
| Alliant Reloder-17 | 36 gr | 80% | 32,808 psi | 53% | 2497 fps | 96.2% |
| Alliant Reloder-23 | <<locked>> | 92% | 30,850 psi | 49% | 2444 fps | 95% |
| Alliant Reloder-26 | <<locked>> | 96% | 37,768 psi | 61% | 2677 fps | 95.3% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 43,584 psi | 70% | 2654 fps | 97.8% |
| Bofors RP3 | <<locked>> | 80% | 37,768 psi | 61% | 2543 fps | 98.4% |
| Bofors RP7 | <<locked>> | 92% | 48,878 psi | 78% | 2707 fps | 95.4% |
| Hodgdon Benchmark | <<locked>> | 80% | 48,370 psi | 78% | 2651 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 80% | 45,687 psi | 73% | 2690 fps | 99.9% |
| Hodgdon CFE223 | <<locked>> | 80% | 49,748 psi | 80% | 2822 fps | 99.3% |
| Hodgdon H322 | <<locked>> | 80% | 53,156 psi | 85% | 2756 fps | 100% |
| Hodgdon H380 | <<locked>> | 80% | 38,522 psi | 62% | 2539 fps | 95.8% |
| Hodgdon H414 | <<locked>> | 92% | 45,484 psi | 73% | 2736 fps | 95.4% |
| Hodgdon H4350 | <<locked>> | 94% | 52,736 psi | 85% | 2808 fps | 95.5% |
| Hodgdon H4895 | <<locked>> | 80% | 45,078 psi | 72% | 2667 fps | 99.3% |
| Hodgdon Hybrid 100V | <<locked>> | 84% | 30,908 psi | 50% | 2392 fps | 95.5% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 41,104 psi | 66% | 2641 fps | 99% |
| Hodgdon Superformance | <<locked>> | 94% | 48,646 psi | 78% | 2812 fps | 95.4% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,774 psi | 43% | 1535 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 43,149 psi | 69% | 2618 fps | 99% |
| IMR 3031 | <<locked>> | 80% | 44,788 psi | 72% | 2664 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 40,016 psi | 64% | 2539 fps | 97.6% |
| IMR 4166 Enduron | <<locked>> | 82% | 45,020 psi | 72% | 2608 fps | 95.1% |
| IMR 4350 | <<locked>> | 96% | 48,863 psi | 78% | 2730 fps | 95.5% |
| IMR 4451 Enduron | <<locked>> | 90% | 47,819 psi | 77% | 2690 fps | 95.7% |
| IMR 4831 | <<locked>> | 86% | 34,301 psi | 55% | 2490 fps | 95% |
| IMR 4895 | <<locked>> | 80% | 41,452 psi | 66% | 2621 fps | 98.4% |
| IMR 8208 XBR | <<locked>> | 80% | 46,586 psi | 75% | 2661 fps | 99.7% |
| Lovex D073.6 | <<locked>> | 80% | 44,179 psi | 71% | 2644 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 44,759 psi | 72% | 2592 fps | 98.9% |
| Lovex S062 | <<locked>> | 80% | 40,248 psi | 65% | 2552 fps | 99.1% |
| Lovex S065 | <<locked>> | 86% | 39,755 psi | 64% | 2539 fps | 95.1% |
| Lovex S070 | <<locked>> | 92% | 44,933 psi | 72% | 2664 fps | 95.4% |
| Norma 201 | <<locked>> | 80% | 44,280 psi | 71% | 2615 fps | 99.6% |
| Norma 202 | <<locked>> | 80% | 44,309 psi | 71% | 2621 fps | 100% |
| Norma 203B | <<locked>> | 80% | 39,958 psi | 64% | 2582 fps | 98% |
| Norma URP | <<locked>> | 86% | 35,549 psi | 57% | 2530 fps | 95.2% |
| Ramshot Big Game | <<locked>> | 80% | 39,378 psi | 63% | 2592 fps | 97.7% |
| Ramshot Hunter | <<locked>> | 92% | 41,930 psi | 67% | 2671 fps | 95.3% |
| Ramshot TAC | <<locked>> | 80% | 46,514 psi | 75% | 2664 fps | 97.1% |
| Ramshot Wild Boar | <<locked>> | 80% | 46,108 psi | 74% | 2690 fps | 99.1% |
| Ramshot X-Terminator | <<locked>> | 80% | 50,111 psi | 80% | 2707 fps | 99.4% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,093 psi | 43% | 1572 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 80% | 52,112 psi | 84% | 2740 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 84% | 43,918 psi | 70% | 2625 fps | 95.5% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 42,163 psi | 68% | 2690 fps | 98% |
| ReloadSwiss RS 60 | 36 gr | 80% | 34,766 psi | 56% | 2562 fps | 99.1% |
| ReloadSwiss RS 62 | <<locked>> | 88% | 37,420 psi | 60% | 2598 fps | 95.7% |
| ReloadSwiss RS 70 | <<locked>> | 90% | 39,813 psi | 64% | 2654 fps | 95.5% |
| Rottweil R 901 | <<locked>> | 80% | 48,370 psi | 78% | 2654 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 42,206 psi | 68% | 2569 fps | 99.3% |
| Rottweil R 903 | <<locked>> | 80% | 35,752 psi | 57% | 2490 fps | 97.6% |
| Rottweil R 907 | <<locked>> | 92% | 48,878 psi | 78% | 2707 fps | 95.4% |
| Shooters World Long Rifle | <<locked>> | 86% | 39,755 psi | 64% | 2539 fps | 95.1% |
| Shooters World Match Rifle | <<locked>> | 80% | 44,179 psi | 71% | 2644 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 40,248 psi | 65% | 2552 fps | 99.1% |
| Shooters World SW4350 | <<locked>> | 92% | 44,933 psi | 72% | 2664 fps | 95.4% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 36,056 psi | 58% | 2526 fps | 96.8% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 44,976 psi | 72% | 2641 fps | 97.3% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 43,062 psi | 69% | 2621 fps | 98.6% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 45,397 psi | 73% | 2566 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 37,884 psi | 61% | 2438 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 92% | 47,210 psi | 76% | 2638 fps | 95.7% |
| Somchem S321 | <<locked>> | 80% | 50,314 psi | 81% | 2740 fps | 100% |
| Somchem S335 | <<locked>> | 80% | 45,063 psi | 72% | 2569 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 44,454 psi | 71% | 2638 fps | 98.8% |
| Somchem S355 | <<locked>> | 80% | 36,463 psi | 58% | 2493 fps | 97.6% |
| Somchem S365 | <<locked>> | 82% | 28,413 psi | 46% | 2379 fps | 95.9% |
| Vihtavuori N130 | <<locked>> | 80% | 50,995 psi | 82% | 2625 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 45,571 psi | 73% | 2559 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 41,524 psi | 67% | 2552 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 41,959 psi | 67% | 2559 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 34,679 psi | 56% | 2431 fps | 98.3% |
| Vihtavuori N160 | <<locked>> | 86% | 37,028 psi | 59% | 2530 fps | 95.7% |
| Vihtavuori N530 | <<locked>> | 80% | 46,804 psi | 75% | 2661 fps | 99.8% |
| Vihtavuori N540 | <<locked>> | 80% | 40,480 psi | 65% | 2549 fps | 99.9% |
| Vihtavuori N550 | <<locked>> | 86% | 36,535 psi | 59% | 2533 fps | 95.3% |
| Vihtavuori N555 | <<locked>> | 92% | 33,069 psi | 53% | 2523 fps | 95.2% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 30,647 psi | 49% | 2349 fps | 95.4% |
| Winchester 748 | <<locked>> | 80% | 46,195 psi | 74% | 2700 fps | 100% |
| Winchester 760 | <<locked>> | 92% | 45,484 psi | 73% | 2736 fps | 95.4% |
| Winchester StaBALL HD | <<locked>> | 96% | 30,951 psi | 50% | 2516 fps | 95.4% |
| Winchester StaBALL Match | <<locked>> | 80% | 42,670 psi | 68% | 2631 fps | 99% |
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 .260 Ackley Improved loaded with the .264 | 122gr | THAC EDH. Alliant Power Pro 2000-MR delivers the highest muzzle velocity at 2,972 fps; across all powders the maximum-charge window runs from 1,719 fps to 2,972 fps. Accurate 4350 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 56–90 %, leaving at least 10 % headroom. The 122.0 gr projectile in 0.264" calls for a 1:7.5 twist; slower twists will usually not stabilise this weight. Accurate 4350, Alliant Reloder-16, Alliant Reloder-23 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, Alliant Reloder-17, Alliant Power Pro 2000-MR rank at the top here: for .260 Ackley Improved with the .264 | 122gr | THAC EDH 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.