Load Specifications
Load data in caliber .260 Rem. with .264 | 139gr | 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-17, ReloadSwiss RS 60 and Winchester 760.
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% | 54,375 psi | 90% | 2536 fps | 100% |
| Accurate 2495 | <<locked>> | 88% | 52,591 psi | 87% | 2559 fps | 100% |
| Accurate 2520 | <<locked>> | 82% | 50,937 psi | 85% | 2575 fps | 100% |
| Accurate 2700 | <<locked>> | 88% | 52,489 psi | 87% | 2569 fps | 97.2% |
| Accurate 3100ᴾ | <<locked>> | 100% | 39,624 psi | 66% | 2464 fps | 96.3% |
| Accurate 4064 | <<locked>> | 90% | 52,692 psi | 88% | 2605 fps | 100% |
| Accurate 4350 | <<locked>> | 98% | 52,388 psi | 87% | 2687 fps | 99.7% |
| ADI AR 2206H | <<locked>> | 86% | 53,417 psi | 89% | 2638 fps | 100% |
| ADI AR 2208 | <<locked>> | 90% | 51,401 psi | 85% | 2592 fps | 99.8% |
| ADI Benchmark 8208 | <<locked>> | 84% | 52,649 psi | 87% | 2592 fps | 100% |
| Alliant AR-Comp | <<locked>> | 84% | 53,505 psi | 89% | 2566 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 88% | 52,997 psi | 88% | 2749 fps | 100% |
| Alliant Reloder- TS 15.5 | <<locked>> | 90% | 51,242 psi | 85% | 2615 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 88% | 51,851 psi | 86% | 2635 fps | 99.9% |
| Alliant Reloder-16ᴾ | <<locked>> | 100% | 54,259 psi | 90% | 2746 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 94% | 51,808 psi | 86% | 2730 fps | 100% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 38,218 psi | 63% | 2497 fps | 99.1% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 42,598 psi | 71% | 2644 fps | 98.5% |
| Baschieri & Pellagri 107 | <<locked>> | 86% | 53,142 psi | 88% | 2654 fps | 99.8% |
| Bofors RP3 | <<locked>> | 90% | 51,387 psi | 85% | 2625 fps | 100% |
| Bofors RP7 | <<locked>> | 94% | 51,721 psi | 86% | 2598 fps | 97.4% |
| Hodgdon Benchmark | <<locked>> | 82% | 51,314 psi | 85% | 2533 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 84% | 51,837 psi | 86% | 2621 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 82% | 53,592 psi | 89% | 2710 fps | 100% |
| Hodgdon H380 | <<locked>> | 90% | 52,460 psi | 87% | 2638 fps | 99.5% |
| Hodgdon H414 | <<locked>> | 96% | 51,967 psi | 86% | 2687 fps | 98.1% |
| Hodgdon H4350 | <<locked>> | 94% | 53,055 psi | 88% | 2654 fps | 97% |
| Hodgdon H4895 | <<locked>> | 86% | 53,940 psi | 90% | 2644 fps | 100% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 50,285 psi | 84% | 2625 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 88% | 53,534 psi | 89% | 2680 fps | 100% |
| Hodgdon Superformance | <<locked>> | 96% | 52,562 psi | 87% | 2723 fps | 97.8% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 35,288 psi | 59% | 1591 fps | 100% |
| Hodgdon VARGET | <<locked>> | 86% | 51,967 psi | 86% | 2602 fps | 100% |
| IMR 3031 | <<locked>> | 86% | 53,954 psi | 90% | 2625 fps | 100% |
| IMR 4064 | <<locked>> | 90% | 54,143 psi | 90% | 2625 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 88% | 54,070 psi | 90% | 2605 fps | 98.2% |
| IMR 4350 | <<locked>> | 98% | 52,185 psi | 87% | 2628 fps | 97.5% |
| IMR 4451 Enduron | <<locked>> | 94% | 53,925 psi | 90% | 2631 fps | 98.2% |
| IMR 4831ᴾ | <<locked>> | 100% | 53,287 psi | 89% | 2684 fps | 99.8% |
| IMR 4895 | <<locked>> | 88% | 53,185 psi | 88% | 2661 fps | 100% |
| IMR 8208 XBR | <<locked>> | 84% | 52,649 psi | 87% | 2592 fps | 100% |
| Lovex D073.6 | <<locked>> | 86% | 52,939 psi | 88% | 2612 fps | 100% |
| Lovex S060 | <<locked>> | 86% | 53,417 psi | 89% | 2572 fps | 100% |
| Lovex S062 | <<locked>> | 90% | 53,853 psi | 89% | 2618 fps | 100% |
| Lovex S065 | <<locked>> | 96% | 52,953 psi | 88% | 2625 fps | 99.1% |
| Lovex S070 | <<locked>> | 98% | 53,954 psi | 90% | 2657 fps | 98.5% |
| Norma 201 | <<locked>> | 86% | 52,344 psi | 87% | 2585 fps | 100% |
| Norma 202 | <<locked>> | 86% | 53,026 psi | 88% | 2589 fps | 100% |
| Norma 203B | <<locked>> | 90% | 54,317 psi | 90% | 2667 fps | 100% |
| Norma 204 | <<locked>> | 98% | 52,446 psi | 87% | 2671 fps | 96.3% |
| Norma URP | <<locked>> | 98% | 51,924 psi | 86% | 2680 fps | 99.7% |
| Ramshot Big Game | <<locked>> | 88% | 51,126 psi | 85% | 2641 fps | 99.9% |
| Ramshot Hunterᴾ | <<locked>> | 100% | 54,201 psi | 90% | 2730 fps | 99.1% |
| Ramshot TAC | <<locked>> | 84% | 52,678 psi | 88% | 2612 fps | 99.1% |
| Ramshot Wild Boar | <<locked>> | 84% | 52,446 psi | 87% | 2628 fps | 100% |
| Ramshot X-Terminator | <<locked>> | 82% | 53,548 psi | 89% | 2595 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 35,839 psi | 60% | 1634 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 90% | 52,924 psi | 88% | 2625 fps | 98.6% |
| ReloadSwiss RS 52 | <<locked>> | 86% | 51,982 psi | 86% | 2690 fps | 99.9% |
| ReloadSwiss RS 60 | <<locked>> | 92% | 51,517 psi | 86% | 2726 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 98% | 51,996 psi | 86% | 2710 fps | 99.6% |
| ReloadSwiss RS 70 | <<locked>> | 98% | 51,837 psi | 86% | 2736 fps | 99.5% |
| Rottweil R 901 | <<locked>> | 84% | 53,185 psi | 88% | 2566 fps | 100% |
| Rottweil R 902 | <<locked>> | 88% | 52,866 psi | 88% | 2585 fps | 100% |
| Rottweil R 903 | <<locked>> | 92% | 51,271 psi | 85% | 2618 fps | 100% |
| Rottweil R 907 | <<locked>> | 94% | 51,721 psi | 86% | 2598 fps | 97.4% |
| Shooters World Long Rifle | <<locked>> | 96% | 52,953 psi | 88% | 2625 fps | 99.1% |
| Shooters World Match Rifle | <<locked>> | 86% | 52,939 psi | 88% | 2612 fps | 100% |
| Shooters World Precision | <<locked>> | 90% | 53,853 psi | 89% | 2618 fps | 100% |
| Shooters World SW4350 | <<locked>> | 98% | 53,954 psi | 90% | 2657 fps | 98.5% |
| SNPE Vectan SP 11 | <<locked>> | 92% | 53,330 psi | 89% | 2680 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 84% | 50,908 psi | 85% | 2585 fps | 99.3% |
| SNPE Vectan SP 9 | <<locked>> | 86% | 52,011 psi | 86% | 2615 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 86% | 53,925 psi | 90% | 2530 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 92% | 54,317 psi | 90% | 2530 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 96% | 53,432 psi | 89% | 2582 fps | 98.1% |
| Somchem S321 | <<locked>> | 82% | 53,809 psi | 89% | 2625 fps | 100% |
| Somchem S335 | <<locked>> | 86% | 53,345 psi | 89% | 2530 fps | 100% |
| Somchem S341 | <<locked>> | 86% | 54,186 psi | 90% | 2628 fps | 100% |
| Somchem S355 | <<locked>> | 92% | 51,837 psi | 86% | 2618 fps | 100% |
| Somchem S365ᴾ | <<locked>> | 100% | 49,545 psi | 82% | 2677 fps | 100% |
| Somchem S385ᴾ | <<locked>> | 100% | 46,108 psi | 77% | 2569 fps | 96.2% |
| Vihtavuori N130 | <<locked>> | 82% | 53,534 psi | 89% | 2487 fps | 100% |
| Vihtavuori N133 | <<locked>> | 86% | 54,215 psi | 90% | 2513 fps | 100% |
| Vihtavuori N135 | <<locked>> | 88% | 52,562 psi | 87% | 2549 fps | 100% |
| Vihtavuori N140 | <<locked>> | 88% | 53,534 psi | 89% | 2569 fps | 100% |
| Vihtavuori N150 | <<locked>> | 94% | 53,098 psi | 88% | 2595 fps | 100% |
| Vihtavuori N160 | <<locked>> | 98% | 54,375 psi | 90% | 2677 fps | 99.8% |
| Vihtavuori N530 | <<locked>> | 84% | 53,113 psi | 88% | 2592 fps | 100% |
| Vihtavuori N540 | <<locked>> | 88% | 51,692 psi | 86% | 2569 fps | 100% |
| Vihtavuori N550 | <<locked>> | 98% | 53,330 psi | 89% | 2680 fps | 99.7% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 41,800 psi | 69% | 2566 fps | 99% |
| Winchester 6.5 StaBALL | <<locked>> | 96% | 51,082 psi | 85% | 2608 fps | 100% |
| Winchester 748 | <<locked>> | 84% | 52,808 psi | 88% | 2635 fps | 100% |
| Winchester 760 | <<locked>> | 96% | 52,402 psi | 87% | 2694 fps | 98.2% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 34,156 psi | 57% | 2500 fps | 99.1% |
| Winchester StaBALL Match | <<locked>> | 86% | 51,880 psi | 86% | 2621 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% | 47,906 psi | 80% | 2451 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 40,074 psi | 67% | 2379 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 47,819 psi | 79% | 2533 fps | 100% |
| Accurate 2700 | <<locked>> | 82% | 42,989 psi | 71% | 2415 fps | 95% |
| Accurate 3100 | <<locked>> | 98% | 36,999 psi | 61% | 2411 fps | 95.5% |
| Accurate 4064 | <<locked>> | 80% | 37,956 psi | 63% | 2375 fps | 100% |
| Accurate 4350 | <<locked>> | 84% | 31,908 psi | 53% | 2316 fps | 95.7% |
| ADI AR 2206H | <<locked>> | 80% | 44,396 psi | 74% | 2493 fps | 99.5% |
| ADI AR 2208 | <<locked>> | 80% | 37,666 psi | 63% | 2352 fps | 97.9% |
| ADI Benchmark 8208 | <<locked>> | 80% | 46,543 psi | 77% | 2500 fps | 100% |
| Alliant AR-Comp | <<locked>> | 80% | 46,818 psi | 78% | 2480 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 40,176 psi | 67% | 2523 fps | 98.5% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 37,072 psi | 62% | 2372 fps | 99.1% |
| Alliant Reloder-15 | <<locked>> | 80% | 40,059 psi | 67% | 2434 fps | 98.6% |
| Alliant Reloder-16 | <<locked>> | 84% | 32,706 psi | 54% | 2336 fps | 95.9% |
| Alliant Reloder-17 | 34.7 gr | 80% | 32,010 psi | 53% | 2349 fps | 97.5% |
| Alliant Reloder-23 | <<locked>> | 90% | 28,065 psi | 47% | 2244 fps | 95.5% |
| Alliant Reloder-26 | <<locked>> | 94% | 34,592 psi | 57% | 2470 fps | 95.9% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 43,569 psi | 72% | 2500 fps | 98.8% |
| Bofors RP3 | <<locked>> | 80% | 36,535 psi | 61% | 2372 fps | 99.1% |
| Bofors RP7 | <<locked>> | 88% | 42,931 psi | 71% | 2451 fps | 95.3% |
| Hodgdon Benchmark | <<locked>> | 80% | 48,312 psi | 80% | 2487 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 80% | 45,020 psi | 75% | 2520 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 80% | 49,893 psi | 83% | 2654 fps | 99.8% |
| Hodgdon H380 | <<locked>> | 80% | 37,608 psi | 62% | 2382 fps | 96.9% |
| Hodgdon H414 | <<locked>> | 88% | 39,711 psi | 66% | 2474 fps | 95.2% |
| Hodgdon H4350 | <<locked>> | 90% | 46,572 psi | 77% | 2552 fps | 95.6% |
| Hodgdon H4895 | <<locked>> | 80% | 44,802 psi | 74% | 2503 fps | 99.8% |
| Hodgdon Hybrid 100V | <<locked>> | 82% | 28,021 psi | 47% | 2188 fps | 95.8% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 40,567 psi | 67% | 2474 fps | 99.6% |
| Hodgdon Superformance | <<locked>> | 90% | 42,206 psi | 70% | 2543 fps | 95.2% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,165 psi | 43% | 1421 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 43,091 psi | 72% | 2461 fps | 99.6% |
| IMR 3031 | <<locked>> | 80% | 44,251 psi | 74% | 2490 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 39,552 psi | 66% | 2385 fps | 98.5% |
| IMR 4166 Enduron | <<locked>> | 80% | 42,047 psi | 70% | 2405 fps | 95.7% |
| IMR 4350 | <<locked>> | 92% | 43,047 psi | 72% | 2477 fps | 95.4% |
| IMR 4451 Enduron | <<locked>> | 86% | 42,018 psi | 70% | 2434 fps | 95.6% |
| IMR 4831 | <<locked>> | 84% | 31,212 psi | 52% | 2283 fps | 95.4% |
| IMR 4895 | <<locked>> | 80% | 41,031 psi | 68% | 2464 fps | 99.2% |
| IMR 8208 XBR | <<locked>> | 80% | 46,543 psi | 77% | 2500 fps | 100% |
| Lovex D073.6 | <<locked>> | 80% | 43,366 psi | 72% | 2470 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 44,483 psi | 74% | 2434 fps | 99.5% |
| Lovex S062 | <<locked>> | 80% | 39,392 psi | 65% | 2388 fps | 99.6% |
| Lovex S065 | <<locked>> | 84% | 36,579 psi | 61% | 2336 fps | 95.6% |
| Lovex S070 | <<locked>> | 88% | 39,291 psi | 65% | 2411 fps | 95.2% |
| Norma 201 | <<locked>> | 80% | 43,047 psi | 72% | 2441 fps | 99.9% |
| Norma 202 | <<locked>> | 80% | 43,584 psi | 72% | 2451 fps | 100% |
| Norma 203B | <<locked>> | 80% | 39,436 psi | 66% | 2425 fps | 98.9% |
| Norma 204 | <<locked>> | 96% | 49,211 psi | 82% | 2618 fps | 95.6% |
| Norma URP | <<locked>> | 84% | 32,518 psi | 54% | 2320 fps | 95.6% |
| Ramshot Big Game | <<locked>> | 80% | 38,827 psi | 65% | 2434 fps | 98.7% |
| Ramshot Hunter | <<locked>> | 88% | 36,521 psi | 61% | 2415 fps | 95% |
| Ramshot TAC | <<locked>> | 80% | 46,441 psi | 77% | 2510 fps | 98.2% |
| Ramshot Wild Boar | <<locked>> | 80% | 45,701 psi | 76% | 2523 fps | 99.6% |
| Ramshot X-Terminator | <<locked>> | 80% | 50,082 psi | 83% | 2546 fps | 99.9% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 26,731 psi | 44% | 1460 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 38,072 psi | 63% | 2365 fps | 95.3% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 41,959 psi | 70% | 2530 fps | 98.9% |
| ReloadSwiss RS 60 | 34.7 gr | 80% | 34,142 psi | 57% | 2408 fps | 99.8% |
| ReloadSwiss RS 62 | <<locked>> | 84% | 31,952 psi | 53% | 2336 fps | 95.2% |
| ReloadSwiss RS 70 | <<locked>> | 86% | 34,563 psi | 57% | 2398 fps | 95.2% |
| Rottweil R 901 | <<locked>> | 80% | 47,021 psi | 78% | 2477 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 41,176 psi | 68% | 2402 fps | 99.7% |
| Rottweil R 903 | <<locked>> | 80% | 34,418 psi | 57% | 2323 fps | 98.4% |
| Rottweil R 907 | <<locked>> | 88% | 42,931 psi | 71% | 2451 fps | 95.3% |
| Shooters World Long Rifle | <<locked>> | 84% | 36,579 psi | 61% | 2336 fps | 95.6% |
| Shooters World Match Rifle | <<locked>> | 80% | 43,366 psi | 72% | 2470 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 39,392 psi | 65% | 2388 fps | 99.6% |
| Shooters World SW4350 | <<locked>> | 88% | 39,291 psi | 65% | 2411 fps | 95.2% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 35,447 psi | 59% | 2372 fps | 97.9% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 44,541 psi | 74% | 2484 fps | 98.4% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 42,656 psi | 71% | 2461 fps | 99.3% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 44,846 psi | 75% | 2402 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 37,260 psi | 62% | 2280 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 88% | 40,712 psi | 68% | 2379 fps | 95.4% |
| Somchem S321 | <<locked>> | 80% | 50,212 psi | 83% | 2572 fps | 100% |
| Somchem S335 | <<locked>> | 80% | 44,106 psi | 73% | 2398 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 44,338 psi | 74% | 2480 fps | 99.5% |
| Somchem S355 | <<locked>> | 80% | 35,230 psi | 59% | 2326 fps | 98.4% |
| Somchem S365 | <<locked>> | 80% | 25,498 psi | 42% | 2172 fps | 96.1% |
| Somchem S385 | <<locked>> | 98% | 42,946 psi | 71% | 2513 fps | 95.4% |
| Vihtavuori N130 | <<locked>> | 80% | 50,705 psi | 84% | 2451 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 45,281 psi | 75% | 2392 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 40,785 psi | 68% | 2382 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 41,307 psi | 69% | 2392 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 33,605 psi | 56% | 2270 fps | 99% |
| Vihtavuori N160 | <<locked>> | 82% | 31,937 psi | 53% | 2277 fps | 95.3% |
| Vihtavuori N530 | <<locked>> | 80% | 46,412 psi | 77% | 2493 fps | 100% |
| Vihtavuori N540 | <<locked>> | 80% | 39,769 psi | 66% | 2385 fps | 100% |
| Vihtavuori N550 | <<locked>> | 84% | 33,562 psi | 56% | 2329 fps | 95.8% |
| Vihtavuori N555 | <<locked>> | 90% | 30,037 psi | 50% | 2313 fps | 95.6% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 29,834 psi | 50% | 2205 fps | 96.7% |
| Winchester 748 | <<locked>> | 80% | 46,151 psi | 77% | 2536 fps | 100% |
| Winchester 760 | 37.4 gr | 88% | 40,030 psi | 67% | 2480 fps | 95.3% |
| Winchester StaBALL HD | <<locked>> | 94% | 27,978 psi | 46% | 2313 fps | 96% |
| Winchester StaBALL Match | <<locked>> | 80% | 42,380 psi | 70% | 2470 fps | 99.6% |
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 .260 Rem. loaded with the .264 | 139gr | Fox Classic Hunter. Alliant Power Pro 2000-MR delivers the highest muzzle velocity at 2,749 fps; across all powders the maximum-charge window runs from 1,591 fps to 2,749 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 (415 MPa), the top charges use 57–90 %, leaving at least 10 % headroom. The 139.0 gr projectile in 0.264" calls for a 1:8.0 twist; slower twists will usually not stabilise this weight. Accurate 3100, 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. Alliant Reloder-17, ReloadSwiss RS 60, Winchester 760 rank at the top here: for .260 Rem. with the .264 | 139gr | 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.