Load Specifications
Load data in caliber .260 Rem. with .264 | 123gr | Warner Tool Co. Flat Line 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% | 51,851 psi | 86% | 2667 fps | 100% |
| Accurate 2460 | <<locked>> | 82% | 53,345 psi | 89% | 2736 fps | 100% |
| Accurate 2495 | <<locked>> | 90% | 53,084 psi | 88% | 2733 fps | 100% |
| Accurate 2520 | <<locked>> | 84% | 51,503 psi | 86% | 2746 fps | 100% |
| Accurate 2700 | <<locked>> | 90% | 53,026 psi | 88% | 2720 fps | 95.9% |
| Accurate 4064 | <<locked>> | 92% | 52,852 psi | 88% | 2772 fps | 100% |
| Accurate 4350ᴾ | <<locked>> | 100% | 52,069 psi | 87% | 2841 fps | 99.1% |
| ADI AR 2206H | <<locked>> | 88% | 54,070 psi | 90% | 2808 fps | 99.8% |
| ADI AR 2208 | <<locked>> | 92% | 51,590 psi | 86% | 2753 fps | 99.3% |
| ADI Benchmark 8208 | <<locked>> | 86% | 52,982 psi | 88% | 2759 fps | 100% |
| Alliant AR-Comp | <<locked>> | 86% | 53,621 psi | 89% | 2740 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 90% | 53,403 psi | 89% | 2917 fps | 99.6% |
| Alliant Reloder- TS 15.5 | <<locked>> | 92% | 51,198 psi | 85% | 2772 fps | 99.9% |
| Alliant Reloder-15 | <<locked>> | 90% | 51,895 psi | 86% | 2792 fps | 99.4% |
| Alliant Reloder-16ᴾ | <<locked>> | 100% | 50,575 psi | 84% | 2844 fps | 99.2% |
| Alliant Reloder-17 | <<locked>> | 96% | 51,503 psi | 86% | 2884 fps | 99.9% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 35,969 psi | 60% | 2579 fps | 97.3% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 39,900 psi | 66% | 2723 fps | 96.1% |
| Baschieri & Pellagri 107 | <<locked>> | 88% | 53,664 psi | 89% | 2818 fps | 99.3% |
| Bofors RP3 | <<locked>> | 92% | 51,663 psi | 86% | 2789 fps | 99.9% |
| Bofors RP7 | <<locked>> | 96% | 52,170 psi | 87% | 2753 fps | 96.1% |
| Hodgdon Benchmark | <<locked>> | 84% | 52,011 psi | 86% | 2700 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 86% | 52,127 psi | 87% | 2785 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 84% | 54,012 psi | 90% | 2884 fps | 99.6% |
| Hodgdon H322 | <<locked>> | 82% | 53,635 psi | 89% | 2753 fps | 100% |
| Hodgdon H380 | <<locked>> | 92% | 52,750 psi | 88% | 2795 fps | 98.8% |
| Hodgdon H414 | <<locked>> | 98% | 52,025 psi | 86% | 2841 fps | 96.9% |
| Hodgdon H4895 | <<locked>> | 86% | 51,053 psi | 85% | 2762 fps | 99.8% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 46,963 psi | 78% | 2730 fps | 99.5% |
| Hodgdon LEVERevolution | <<locked>> | 90% | 53,476 psi | 89% | 2844 fps | 100% |
| Hodgdon Superformance | <<locked>> | 98% | 52,910 psi | 88% | 2874 fps | 96.4% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 35,288 psi | 59% | 1699 fps | 100% |
| Hodgdon VARGET | <<locked>> | 88% | 52,562 psi | 87% | 2772 fps | 99.9% |
| IMR 3031 | <<locked>> | 88% | 53,998 psi | 90% | 2799 fps | 100% |
| IMR 4064 | <<locked>> | 92% | 54,331 psi | 90% | 2785 fps | 99.7% |
| IMR 4166 Enduron | <<locked>> | 88% | 51,692 psi | 86% | 2717 fps | 96.6% |
| IMR 4350ᴾ | <<locked>> | 100% | 52,141 psi | 87% | 2776 fps | 96.1% |
| IMR 4451 Enduron | <<locked>> | 96% | 54,317 psi | 90% | 2789 fps | 97% |
| IMR 4831ᴾ | <<locked>> | 100% | 49,676 psi | 83% | 2785 fps | 98.8% |
| IMR 4895 | <<locked>> | 90% | 53,185 psi | 88% | 2825 fps | 99.8% |
| IMR 8208 XBR | <<locked>> | 86% | 52,982 psi | 88% | 2759 fps | 100% |
| Lovex D073.5 | <<locked>> | 82% | 53,301 psi | 89% | 2746 fps | 100% |
| Lovex D073.6 | <<locked>> | 88% | 53,388 psi | 89% | 2782 fps | 100% |
| Lovex S060 | <<locked>> | 88% | 53,954 psi | 90% | 2736 fps | 99.8% |
| Lovex S062 | <<locked>> | 92% | 54,056 psi | 90% | 2782 fps | 100% |
| Lovex S065 | <<locked>> | 98% | 53,258 psi | 88% | 2779 fps | 98.2% |
| Lovex S070ᴾ | <<locked>> | 100% | 54,056 psi | 90% | 2812 fps | 97.4% |
| Norma 201 | <<locked>> | 88% | 52,852 psi | 88% | 2753 fps | 100% |
| Norma 202 | <<locked>> | 88% | 53,258 psi | 88% | 2759 fps | 100% |
| Norma 203B | <<locked>> | 90% | 51,068 psi | 85% | 2782 fps | 99.6% |
| Norma URPᴾ | <<locked>> | 100% | 51,648 psi | 86% | 2835 fps | 99% |
| Ramshot Big Game | <<locked>> | 90% | 51,416 psi | 85% | 2805 fps | 99.6% |
| Ramshot Hunterᴾ | <<locked>> | 100% | 50,517 psi | 84% | 2825 fps | 97.4% |
| Ramshot TAC | <<locked>> | 86% | 53,563 psi | 89% | 2776 fps | 98.4% |
| Ramshot Wild Boar | <<locked>> | 86% | 52,750 psi | 88% | 2792 fps | 99.7% |
| Ramshot X-Terminator | <<locked>> | 84% | 54,215 psi | 90% | 2762 fps | 99.7% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 35,462 psi | 59% | 1736 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 82% | 52,533 psi | 87% | 2740 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 92% | 53,185 psi | 88% | 2779 fps | 97.5% |
| ReloadSwiss RS 52 | <<locked>> | 88% | 51,967 psi | 86% | 2858 fps | 99.5% |
| ReloadSwiss RS 60 | <<locked>> | 94% | 51,300 psi | 85% | 2887 fps | 100% |
| ReloadSwiss RS 62ᴾ | <<locked>> | 100% | 51,619 psi | 86% | 2861 fps | 98.9% |
| ReloadSwiss RS 70ᴾ | <<locked>> | 100% | 52,286 psi | 87% | 2890 fps | 98.6% |
| Rottweil R 901 | <<locked>> | 86% | 53,780 psi | 89% | 2736 fps | 100% |
| Rottweil R 902 | <<locked>> | 90% | 53,388 psi | 89% | 2753 fps | 100% |
| Rottweil R 903 | <<locked>> | 94% | 51,532 psi | 86% | 2779 fps | 99.9% |
| Rottweil R 907 | <<locked>> | 96% | 52,170 psi | 87% | 2753 fps | 96.1% |
| Shooters World Long Rifle | <<locked>> | 98% | 53,258 psi | 88% | 2779 fps | 98.2% |
| Shooters World Match Rifle | <<locked>> | 88% | 53,388 psi | 89% | 2782 fps | 100% |
| Shooters World Precision | <<locked>> | 92% | 54,056 psi | 90% | 2782 fps | 100% |
| Shooters World SW4350ᴾ | <<locked>> | 100% | 54,056 psi | 90% | 2812 fps | 97.4% |
| SNPE Vectan SP 11 | <<locked>> | 94% | 53,171 psi | 88% | 2841 fps | 99.7% |
| SNPE Vectan SP 7 | <<locked>> | 86% | 51,764 psi | 86% | 2753 fps | 98.5% |
| SNPE Vectan SP 9 | <<locked>> | 88% | 52,460 psi | 87% | 2776 fps | 99.7% |
| SNPE Vectan Tubal 3000 | <<locked>> | 86% | 51,430 psi | 85% | 2654 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 92% | 51,343 psi | 85% | 2654 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 98% | 53,751 psi | 89% | 2733 fps | 97% |
| Somchem S321 | <<locked>> | 84% | 54,302 psi | 90% | 2792 fps | 100% |
| Somchem S335 | <<locked>> | 88% | 53,896 psi | 90% | 2697 fps | 100% |
| Somchem S341 | <<locked>> | 86% | 51,256 psi | 85% | 2743 fps | 99.6% |
| Somchem S355 | <<locked>> | 94% | 52,214 psi | 87% | 2782 fps | 99.9% |
| Somchem S365ᴾ | <<locked>> | 100% | 45,992 psi | 76% | 2782 fps | 100% |
| Vihtavuori N130 | <<locked>> | 84% | 54,462 psi | 90% | 2664 fps | 100% |
| Vihtavuori N133 | <<locked>> | 86% | 51,590 psi | 86% | 2641 fps | 100% |
| Vihtavuori N135 | <<locked>> | 90% | 52,794 psi | 88% | 2723 fps | 100% |
| Vihtavuori N140 | <<locked>> | 90% | 53,650 psi | 89% | 2736 fps | 100% |
| Vihtavuori N150 | <<locked>> | 96% | 53,374 psi | 89% | 2759 fps | 100% |
| Vihtavuori N160ᴾ | <<locked>> | 100% | 54,056 psi | 90% | 2828 fps | 99.2% |
| Vihtavuori N530 | <<locked>> | 86% | 53,447 psi | 89% | 2756 fps | 100% |
| Vihtavuori N540 | <<locked>> | 90% | 52,112 psi | 87% | 2736 fps | 100% |
| Vihtavuori N550ᴾ | <<locked>> | 100% | 53,011 psi | 88% | 2835 fps | 99% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 38,696 psi | 64% | 2654 fps | 97.2% |
| Winchester 6.5 StaBALL | <<locked>> | 98% | 51,285 psi | 85% | 2762 fps | 99.9% |
| Winchester 748 | <<locked>> | 86% | 53,011 psi | 88% | 2802 fps | 100% |
| Winchester 760 | <<locked>> | 98% | 52,025 psi | 86% | 2841 fps | 96.9% |
| Winchester StaBALL Match | <<locked>> | 88% | 52,069 psi | 87% | 2785 fps | 99.9% |
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% | 45,847 psi | 76% | 2579 fps | 100% |
| Accurate 2460 | <<locked>> | 80% | 49,879 psi | 83% | 2684 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 38,334 psi | 64% | 2500 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 45,150 psi | 75% | 2648 fps | 100% |
| Accurate 2700 | <<locked>> | 88% | 49,574 psi | 82% | 2667 fps | 95.2% |
| Accurate 4064 | <<locked>> | 80% | 36,260 psi | 60% | 2490 fps | 99.8% |
| Accurate 4350 | <<locked>> | 88% | 34,461 psi | 57% | 2510 fps | 95% |
| ADI AR 2206H | <<locked>> | 80% | 41,974 psi | 70% | 2598 fps | 98.4% |
| ADI AR 2208 | <<locked>> | 80% | 35,650 psi | 59% | 2448 fps | 96% |
| ADI Benchmark 8208 | <<locked>> | 80% | 43,990 psi | 73% | 2608 fps | 99.5% |
| Alliant AR-Comp | <<locked>> | 80% | 43,772 psi | 73% | 2602 fps | 100% |
| Alliant Power Pro 2000-MR | 35.8 gr | 80% | 37,956 psi | 63% | 2615 fps | 96.4% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 35,230 psi | 59% | 2474 fps | 97.6% |
| Alliant Reloder-15 | <<locked>> | 80% | 37,739 psi | 63% | 2530 fps | 96.9% |
| Alliant Reloder-16 | <<locked>> | 88% | 35,085 psi | 58% | 2523 fps | 95.1% |
| Alliant Reloder-17 | 36.2 gr | 82% | 32,518 psi | 54% | 2487 fps | 96% |
| Alliant Reloder-23 | <<locked>> | 96% | 31,981 psi | 53% | 2474 fps | 95.6% |
| Alliant Reloder-26 | <<locked>> | 98% | 37,231 psi | 62% | 2657 fps | 95% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 41,104 psi | 68% | 2598 fps | 97.2% |
| Bofors RP3 | <<locked>> | 80% | 34,650 psi | 58% | 2474 fps | 97.6% |
| Bofors RP7 | <<locked>> | 94% | 49,153 psi | 82% | 2700 fps | 95.4% |
| Hodgdon Benchmark | <<locked>> | 80% | 45,876 psi | 76% | 2602 fps | 99.8% |
| Hodgdon BL-C2 | <<locked>> | 80% | 42,540 psi | 71% | 2628 fps | 99.6% |
| Hodgdon CFE223 | <<locked>> | 80% | 46,992 psi | 78% | 2769 fps | 98.9% |
| Hodgdon H322 | <<locked>> | 80% | 50,386 psi | 84% | 2707 fps | 100% |
| Hodgdon H380 | <<locked>> | 82% | 37,985 psi | 63% | 2526 fps | 95.5% |
| Hodgdon H414 | <<locked>> | 94% | 45,324 psi | 75% | 2723 fps | 95.3% |
| Hodgdon H4895 | <<locked>> | 80% | 42,293 psi | 70% | 2608 fps | 98.9% |
| Hodgdon Hybrid 100V | <<locked>> | 86% | 30,240 psi | 50% | 2372 fps | 95.1% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 38,159 psi | 63% | 2575 fps | 98.5% |
| Hodgdon Superformance | <<locked>> | 96% | 49,023 psi | 81% | 2805 fps | 95.5% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,063 psi | 43% | 1512 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 40,669 psi | 68% | 2562 fps | 98.5% |
| IMR 3031 | <<locked>> | 80% | 41,771 psi | 69% | 2612 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 37,405 psi | 62% | 2480 fps | 96.8% |
| IMR 4166 Enduron | <<locked>> | 84% | 45,585 psi | 76% | 2612 fps | 95.1% |
| IMR 4350 | <<locked>> | 98% | 49,110 psi | 82% | 2723 fps | 95.4% |
| IMR 4451 Enduron | <<locked>> | 92% | 47,950 psi | 80% | 2684 fps | 95.7% |
| IMR 4831 | <<locked>> | 90% | 35,781 psi | 59% | 2523 fps | 95.6% |
| IMR 4895 | <<locked>> | 80% | 38,653 psi | 64% | 2559 fps | 97.7% |
| IMR 8208 XBR | <<locked>> | 80% | 43,990 psi | 73% | 2608 fps | 99.5% |
| Lovex D073.5 | <<locked>> | 80% | 49,806 psi | 83% | 2694 fps | 100% |
| Lovex D073.6 | <<locked>> | 80% | 40,683 psi | 68% | 2579 fps | 99.8% |
| Lovex S060 | <<locked>> | 80% | 42,308 psi | 70% | 2539 fps | 98.4% |
| Lovex S062 | <<locked>> | 80% | 37,333 psi | 62% | 2490 fps | 98.5% |
| Lovex S065 | <<locked>> | 90% | 41,713 psi | 69% | 2575 fps | 95.7% |
| Lovex S070 | <<locked>> | 94% | 44,817 psi | 74% | 2654 fps | 95.3% |
| Norma 201 | <<locked>> | 80% | 41,220 psi | 68% | 2556 fps | 99.2% |
| Norma 202 | <<locked>> | 80% | 41,452 psi | 69% | 2566 fps | 100% |
| Norma 203B | <<locked>> | 80% | 37,130 psi | 62% | 2520 fps | 97.3% |
| Norma URP | <<locked>> | 88% | 35,041 psi | 58% | 2513 fps | 95% |
| Ramshot Big Game | <<locked>> | 80% | 36,550 psi | 61% | 2530 fps | 96.9% |
| Ramshot Hunter | <<locked>> | 94% | 41,626 psi | 69% | 2661 fps | 95.1% |
| Ramshot TAC | <<locked>> | 80% | 44,077 psi | 73% | 2612 fps | 96.5% |
| Ramshot Wild Boar | <<locked>> | 80% | 43,178 psi | 72% | 2628 fps | 98.6% |
| Ramshot X-Terminator | <<locked>> | 80% | 47,630 psi | 79% | 2657 fps | 99.1% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 26,310 psi | 44% | 1549 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 80% | 49,472 psi | 82% | 2694 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 86% | 43,888 psi | 73% | 2618 fps | 95.5% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 39,233 psi | 65% | 2625 fps | 97.3% |
| ReloadSwiss RS 60 | 35.3 gr | 80% | 32,372 psi | 54% | 2497 fps | 98.4% |
| ReloadSwiss RS 62 | <<locked>> | 90% | 36,608 psi | 61% | 2579 fps | 95.3% |
| ReloadSwiss RS 70 | <<locked>> | 92% | 39,842 psi | 66% | 2648 fps | 95.4% |
| Rottweil R 901 | <<locked>> | 80% | 44,947 psi | 75% | 2595 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 39,146 psi | 65% | 2507 fps | 98.8% |
| Rottweil R 903 | <<locked>> | 80% | 32,692 psi | 54% | 2421 fps | 96.6% |
| Rottweil R 907 | <<locked>> | 94% | 49,153 psi | 82% | 2700 fps | 95.4% |
| Shooters World Long Rifle | <<locked>> | 90% | 41,713 psi | 69% | 2575 fps | 95.7% |
| Shooters World Match Rifle | <<locked>> | 80% | 40,683 psi | 68% | 2579 fps | 99.8% |
| Shooters World Precision | <<locked>> | 80% | 37,333 psi | 62% | 2490 fps | 98.5% |
| Shooters World SW4350 | <<locked>> | 94% | 44,817 psi | 74% | 2654 fps | 95.3% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 33,533 psi | 56% | 2464 fps | 95.9% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 42,206 psi | 70% | 2585 fps | 96.6% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 40,466 psi | 67% | 2566 fps | 98% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 42,699 psi | 71% | 2513 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 35,317 psi | 59% | 2385 fps | 99.9% |
| SNPE Vectan Tubal 7000 | <<locked>> | 94% | 47,079 psi | 78% | 2628 fps | 95.6% |
| Somchem S321 | <<locked>> | 80% | 47,543 psi | 79% | 2687 fps | 99.9% |
| Somchem S335 | <<locked>> | 80% | 42,293 psi | 70% | 2516 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 41,872 psi | 70% | 2582 fps | 98.3% |
| Somchem S355 | <<locked>> | 80% | 33,576 psi | 56% | 2425 fps | 96.7% |
| Somchem S365 | <<locked>> | 84% | 27,499 psi | 46% | 2352 fps | 95.4% |
| Vihtavuori N130 | <<locked>> | 80% | 48,240 psi | 80% | 2579 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 42,917 psi | 71% | 2510 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 38,435 psi | 64% | 2497 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 39,262 psi | 65% | 2503 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 31,923 psi | 53% | 2365 fps | 97.5% |
| Vihtavuori N160 | <<locked>> | 88% | 36,709 psi | 61% | 2516 fps | 95.5% |
| Vihtavuori N530 | <<locked>> | 80% | 44,135 psi | 73% | 2605 fps | 99.5% |
| Vihtavuori N540 | <<locked>> | 80% | 37,811 psi | 63% | 2493 fps | 99.8% |
| Vihtavuori N550 | <<locked>> | 88% | 35,998 psi | 60% | 2520 fps | 95.1% |
| Vihtavuori N555 | <<locked>> | 96% | 34,142 psi | 57% | 2549 fps | 95.7% |
| Winchester 6.5 StaBALL | <<locked>> | 82% | 30,371 psi | 50% | 2339 fps | 95.2% |
| Winchester 748 | <<locked>> | 80% | 43,439 psi | 72% | 2648 fps | 99.8% |
| Winchester 760 | <<locked>> | 94% | 45,672 psi | 76% | 2730 fps | 95.4% |
| Winchester StaBALL Match | <<locked>> | 80% | 39,972 psi | 66% | 2572 fps | 98.5% |
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 96 powders for .260 Rem. loaded with the .264 | 123gr | Warner Tool Co. Flat Line. Alliant Power Pro 2000-MR delivers the highest muzzle velocity at 2,917 fps; across all powders the maximum-charge window runs from 1,699 fps to 2,917 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 (415 MPa), the top charges use 59–90 %, leaving at least 10 % headroom. The 123.0 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 Rem. with the .264 | 123gr | Warner Tool Co. Flat Line 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.