Load Specifications
Load data in caliber .260 Rem. with .263 | 139gr | Prvi Partizan FMJ BT bullet and 98 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are ReloadSwiss RS 70, Alliant Reloder-16 and Hodgdon Superformance.
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>> | 84% | 51,271 psi | 85% | 2552 fps | 100% |
| Accurate 2700 | <<locked>> | 86% | 53,388 psi | 89% | 2608 fps | 97.9% |
| Accurate 3100ᴾ | <<locked>> | 100% | 45,150 psi | 75% | 2575 fps | 98.1% |
| Accurate 4064 | <<locked>> | 86% | 51,605 psi | 86% | 2602 fps | 100% |
| Accurate 4350 | <<locked>> | 94% | 50,966 psi | 85% | 2684 fps | 99.8% |
| ADI AR 2206H | <<locked>> | 82% | 51,213 psi | 85% | 2625 fps | 100% |
| ADI AR 2208 | <<locked>> | 88% | 52,591 psi | 87% | 2631 fps | 100% |
| ADI AR 2209ᴾ | <<locked>> | 100% | 52,866 psi | 88% | 2720 fps | 97% |
| ADI Benchmark 8208 | <<locked>> | 82% | 53,403 psi | 89% | 2621 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 86% | 54,433 psi | 90% | 2792 fps | 100% |
| Alliant Power Pro Varmintᴾ | <<locked>> | 100% | 52,475 psi | 87% | 2717 fps | 97.1% |
| Alliant Reloder- TS 15.5 | <<locked>> | 88% | 52,808 psi | 88% | 2654 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 86% | 53,011 psi | 88% | 2671 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 96% | 52,257 psi | 87% | 2740 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 92% | 53,084 psi | 88% | 2766 fps | 100% |
| Alliant Reloder-19ᴾ | <<locked>> | 100% | 51,706 psi | 86% | 2707 fps | 97% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 42,641 psi | 71% | 2602 fps | 99.9% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 37,753 psi | 63% | 2513 fps | 96.7% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 48,109 psi | 80% | 2769 fps | 99.6% |
| Baschieri & Pellagri 107 | <<locked>> | 84% | 54,215 psi | 90% | 2690 fps | 100% |
| Bofors RP3 | <<locked>> | 88% | 53,084 psi | 88% | 2664 fps | 100% |
| Bofors RP7 | <<locked>> | 92% | 53,055 psi | 88% | 2644 fps | 98.1% |
| Hodgdon BL-C2 | <<locked>> | 82% | 52,968 psi | 88% | 2651 fps | 100% |
| Hodgdon H380 | <<locked>> | 88% | 53,766 psi | 89% | 2677 fps | 99.8% |
| Hodgdon H414 | <<locked>> | 94% | 53,650 psi | 89% | 2733 fps | 98.7% |
| Hodgdon H4350 | <<locked>> | 92% | 54,215 psi | 90% | 2697 fps | 97.7% |
| Hodgdon H4895 | <<locked>> | 82% | 51,750 psi | 86% | 2631 fps | 100% |
| Hodgdon Hybrid 100V | <<locked>> | 98% | 52,199 psi | 87% | 2671 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 84% | 51,459 psi | 85% | 2667 fps | 100% |
| Hodgdon Superformance | <<locked>> | 94% | 54,128 psi | 90% | 2772 fps | 98.5% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 35,926 psi | 60% | 1627 fps | 100% |
| Hodgdon VARGET | <<locked>> | 84% | 52,924 psi | 88% | 2638 fps | 100% |
| IMR 3031 | <<locked>> | 82% | 52,025 psi | 86% | 2615 fps | 100% |
| IMR 4064 | <<locked>> | 86% | 51,953 psi | 86% | 2615 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 84% | 51,590 psi | 86% | 2592 fps | 98.3% |
| IMR 4350 | <<locked>> | 96% | 53,490 psi | 89% | 2671 fps | 98.2% |
| IMR 4451 Enduron | <<locked>> | 90% | 51,634 psi | 86% | 2621 fps | 98.2% |
| IMR 4831 | <<locked>> | 96% | 51,924 psi | 86% | 2680 fps | 99.9% |
| IMR 4895 | <<locked>> | 86% | 54,360 psi | 90% | 2697 fps | 100% |
| IMR 8208 XBR | <<locked>> | 82% | 53,403 psi | 89% | 2621 fps | 100% |
| Lovex D073.6 | <<locked>> | 82% | 51,010 psi | 85% | 2598 fps | 100% |
| Lovex S060 | <<locked>> | 84% | 53,940 psi | 90% | 2602 fps | 100% |
| Lovex S062 | <<locked>> | 86% | 52,011 psi | 86% | 2612 fps | 100% |
| Lovex S065 | <<locked>> | 94% | 54,317 psi | 90% | 2664 fps | 99.5% |
| Lovex S070 | <<locked>> | 94% | 52,156 psi | 87% | 2654 fps | 98.6% |
| Lovex S071ᴾ | <<locked>> | 100% | 37,536 psi | 62% | 2434 fps | 96.1% |
| Norma 201 | <<locked>> | 84% | 53,417 psi | 89% | 2621 fps | 100% |
| Norma 202 | <<locked>> | 84% | 53,969 psi | 90% | 2618 fps | 100% |
| Norma 203B | <<locked>> | 86% | 52,272 psi | 87% | 2657 fps | 100% |
| Norma 204 | <<locked>> | 96% | 53,896 psi | 90% | 2717 fps | 97.1% |
| Norma MRPᴾ | <<locked>> | 100% | 47,761 psi | 79% | 2723 fps | 97.7% |
| Norma URP | <<locked>> | 96% | 53,824 psi | 89% | 2726 fps | 99.9% |
| Ramshot Big Game | <<locked>> | 86% | 52,736 psi | 88% | 2684 fps | 100% |
| Ramshot Hunter | <<locked>> | 96% | 52,330 psi | 87% | 2723 fps | 99.1% |
| Ramshot TAC | <<locked>> | 82% | 53,664 psi | 89% | 2648 fps | 99.5% |
| Ramshot Wild Boar | <<locked>> | 82% | 53,301 psi | 89% | 2661 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 36,535 psi | 61% | 1667 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 88% | 54,201 psi | 90% | 2667 fps | 99.1% |
| ReloadSwiss RS 52 | <<locked>> | 84% | 53,403 psi | 89% | 2730 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 90% | 52,924 psi | 88% | 2762 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 94% | 50,691 psi | 84% | 2707 fps | 99.7% |
| ReloadSwiss RS 70 | <<locked>> | 96% | 53,548 psi | 89% | 2785 fps | 99.8% |
| Rottweil R 901 | <<locked>> | 82% | 54,346 psi | 90% | 2598 fps | 100% |
| Rottweil R 902 | <<locked>> | 86% | 53,853 psi | 89% | 2618 fps | 100% |
| Rottweil R 903 | <<locked>> | 90% | 52,982 psi | 88% | 2657 fps | 100% |
| Rottweil R 905ᴾ | <<locked>> | 100% | 50,676 psi | 84% | 2694 fps | 97% |
| Rottweil R 907 | <<locked>> | 92% | 53,055 psi | 88% | 2644 fps | 98.1% |
| Shooters World Long Rifle | <<locked>> | 94% | 54,317 psi | 90% | 2664 fps | 99.5% |
| Shooters World Match Rifle | <<locked>> | 82% | 51,010 psi | 85% | 2598 fps | 100% |
| Shooters World Precision | <<locked>> | 86% | 52,011 psi | 86% | 2612 fps | 100% |
| Shooters World SW4350 | <<locked>> | 94% | 52,156 psi | 87% | 2654 fps | 98.6% |
| SNPE Vectan SP 11 | <<locked>> | 88% | 51,416 psi | 85% | 2671 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 82% | 52,272 psi | 87% | 2628 fps | 99.6% |
| SNPE Vectan SP 9 | <<locked>> | 84% | 52,939 psi | 88% | 2644 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 82% | 51,590 psi | 86% | 2516 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 88% | 51,924 psi | 86% | 2520 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 94% | 54,389 psi | 90% | 2621 fps | 98.6% |
| SNPE Vectan Tubal 8000ᴾ | <<locked>> | 100% | 50,183 psi | 83% | 2687 fps | 96.8% |
| Somchem S335 | <<locked>> | 84% | 54,172 psi | 90% | 2556 fps | 100% |
| Somchem S341 | <<locked>> | 82% | 51,851 psi | 86% | 2618 fps | 100% |
| Somchem S355 | <<locked>> | 90% | 53,359 psi | 89% | 2657 fps | 100% |
| Somchem S365 | <<locked>> | 98% | 51,996 psi | 86% | 2726 fps | 100% |
| Somchem S385ᴾ | <<locked>> | 100% | 51,401 psi | 85% | 2674 fps | 97.8% |
| Vihtavuori N133 | <<locked>> | 82% | 51,953 psi | 86% | 2500 fps | 100% |
| Vihtavuori N135 | <<locked>> | 86% | 53,853 psi | 89% | 2582 fps | 100% |
| Vihtavuori N140 | <<locked>> | 84% | 51,155 psi | 85% | 2556 fps | 100% |
| Vihtavuori N150 | <<locked>> | 90% | 51,169 psi | 85% | 2585 fps | 100% |
| Vihtavuori N160 | <<locked>> | 94% | 52,417 psi | 87% | 2667 fps | 99.8% |
| Vihtavuori N530 | <<locked>> | 82% | 53,795 psi | 89% | 2621 fps | 100% |
| Vihtavuori N540 | <<locked>> | 86% | 52,562 psi | 87% | 2595 fps | 100% |
| Vihtavuori N550 | <<locked>> | 94% | 51,459 psi | 85% | 2674 fps | 99.7% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 47,340 psi | 79% | 2671 fps | 99.8% |
| Winchester 6.5 StaBALL | <<locked>> | 94% | 52,301 psi | 87% | 2648 fps | 100% |
| Winchester 748 | <<locked>> | 82% | 53,998 psi | 90% | 2667 fps | 100% |
| Winchester 760 | <<locked>> | 94% | 54,012 psi | 90% | 2740 fps | 98.8% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 38,232 psi | 64% | 2628 fps | 100% |
| Winchester StaBALL Match | <<locked>> | 84% | 52,794 psi | 88% | 2651 fps | 100% |
| Winchester Supreme 780ᴾ | <<locked>> | 100% | 48,051 psi | 80% | 2608 fps | 95.9% |
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 2495 | <<locked>> | 80% | 45,150 psi | 75% | 2467 fps | 100% |
| Accurate 2700 | <<locked>> | 80% | 43,801 psi | 73% | 2451 fps | 95.9% |
| Accurate 3100 | <<locked>> | 92% | 34,519 psi | 57% | 2372 fps | 95.1% |
| Accurate 4064 | <<locked>> | 80% | 42,699 psi | 71% | 2467 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 31,763 psi | 53% | 2320 fps | 96% |
| ADI AR 2206H | <<locked>> | 80% | 48,399 psi | 80% | 2579 fps | 99.9% |
| ADI AR 2208 | <<locked>> | 80% | 40,973 psi | 68% | 2438 fps | 98.9% |
| ADI AR 2209 | <<locked>> | 96% | 46,412 psi | 77% | 2612 fps | 95.5% |
| ADI Benchmark 8208 | <<locked>> | 80% | 50,473 psi | 84% | 2579 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 44,324 psi | 74% | 2625 fps | 99.5% |
| Alliant Power Pro Varmint | <<locked>> | 96% | 46,079 psi | 77% | 2608 fps | 95.6% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 41,017 psi | 68% | 2464 fps | 99.8% |
| Alliant Reloder-15 | <<locked>> | 80% | 44,005 psi | 73% | 2523 fps | 99.5% |
| Alliant Reloder-16 | 34.4 gr | 80% | 31,749 psi | 53% | 2326 fps | 96% |
| Alliant Reloder-17 | <<locked>> | 80% | 35,491 psi | 59% | 2448 fps | 98.9% |
| Alliant Reloder-19 | <<locked>> | 96% | 45,469 psi | 76% | 2598 fps | 95.5% |
| Alliant Reloder-23 | <<locked>> | 86% | 27,804 psi | 46% | 2251 fps | 95.9% |
| Alliant Reloder-25 | <<locked>> | 98% | 35,462 psi | 59% | 2457 fps | 95.7% |
| Alliant Reloder-26 | <<locked>> | 88% | 31,633 psi | 53% | 2408 fps | 95.1% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 47,442 psi | 79% | 2585 fps | 99.6% |
| Bofors RP3 | <<locked>> | 80% | 40,698 psi | 68% | 2464 fps | 99.8% |
| Bofors RP7 | <<locked>> | 84% | 41,321 psi | 69% | 2441 fps | 95.4% |
| Hodgdon BL-C2 | <<locked>> | 80% | 49,719 psi | 83% | 2605 fps | 100% |
| Hodgdon H380 | <<locked>> | 80% | 41,408 psi | 69% | 2470 fps | 98.2% |
| Hodgdon H414 | <<locked>> | 84% | 38,638 psi | 64% | 2467 fps | 95.4% |
| Hodgdon H4350 | <<locked>> | 86% | 44,744 psi | 74% | 2539 fps | 95.6% |
| Hodgdon H4895 | <<locked>> | 80% | 48,863 psi | 81% | 2589 fps | 100% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 29,298 psi | 49% | 2234 fps | 96.9% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 44,817 psi | 74% | 2562 fps | 100% |
| Hodgdon Superformance | 42.1 gr | 86% | 40,509 psi | 67% | 2533 fps | 95.3% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,745 psi | 44% | 1450 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 46,528 psi | 77% | 2536 fps | 100% |
| IMR 3031 | <<locked>> | 80% | 48,965 psi | 81% | 2572 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 43,047 psi | 72% | 2467 fps | 99.4% |
| IMR 4166 Enduron | <<locked>> | 80% | 45,455 psi | 76% | 2490 fps | 97.1% |
| IMR 4350 | <<locked>> | 88% | 41,771 psi | 69% | 2474 fps | 95.6% |
| IMR 4451 Enduron | <<locked>> | 82% | 40,379 psi | 67% | 2425 fps | 95.7% |
| IMR 4831 | <<locked>> | 80% | 30,690 psi | 51% | 2277 fps | 95.6% |
| IMR 4895 | <<locked>> | 80% | 45,092 psi | 75% | 2552 fps | 99.8% |
| IMR 8208 XBR | <<locked>> | 80% | 50,473 psi | 84% | 2579 fps | 100% |
| Lovex D073.6 | <<locked>> | 80% | 47,718 psi | 79% | 2552 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 47,863 psi | 80% | 2510 fps | 99.9% |
| Lovex S062 | <<locked>> | 80% | 43,178 psi | 72% | 2470 fps | 100% |
| Lovex S065 | <<locked>> | 80% | 35,549 psi | 59% | 2329 fps | 95.8% |
| Lovex S070 | <<locked>> | 84% | 38,159 psi | 63% | 2405 fps | 95.4% |
| Lovex S071 | <<locked>> | 98% | 35,331 psi | 59% | 2388 fps | 95.4% |
| Norma 201 | <<locked>> | 80% | 47,297 psi | 79% | 2530 fps | 100% |
| Norma 202 | <<locked>> | 80% | 47,747 psi | 79% | 2530 fps | 100% |
| Norma 203B | <<locked>> | 80% | 43,366 psi | 72% | 2513 fps | 99.6% |
| Norma 204 | <<locked>> | 92% | 47,195 psi | 78% | 2608 fps | 95.7% |
| Norma MRP | <<locked>> | 94% | 39,262 psi | 65% | 2556 fps | 95.2% |
| Norma URP | <<locked>> | 80% | 31,995 psi | 53% | 2320 fps | 95.9% |
| Ramshot Big Game | <<locked>> | 80% | 43,105 psi | 72% | 2530 fps | 99.5% |
| Ramshot Hunter | <<locked>> | 84% | 35,346 psi | 59% | 2405 fps | 95.2% |
| Ramshot TAC | <<locked>> | 80% | 50,125 psi | 83% | 2592 fps | 99.1% |
| Ramshot Wild Boar | <<locked>> | 80% | 50,053 psi | 83% | 2612 fps | 100% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,064 psi | 45% | 1486 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 41,785 psi | 69% | 2457 fps | 96.9% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 46,673 psi | 78% | 2625 fps | 99.7% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 37,768 psi | 63% | 2503 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 31,212 psi | 52% | 2326 fps | 95.3% |
| ReloadSwiss RS 70 | 38.6 gr | 82% | 33,330 psi | 55% | 2385 fps | 95.3% |
| Rottweil R 901 | <<locked>> | 80% | 51,358 psi | 85% | 2556 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 45,063 psi | 75% | 2484 fps | 100% |
| Rottweil R 903 | <<locked>> | 80% | 38,508 psi | 64% | 2418 fps | 99.4% |
| Rottweil R 905 | <<locked>> | 96% | 44,266 psi | 74% | 2585 fps | 95.4% |
| Rottweil R 907 | <<locked>> | 84% | 41,321 psi | 69% | 2441 fps | 95.4% |
| Shooters World Long Rifle | <<locked>> | 80% | 35,549 psi | 59% | 2329 fps | 95.8% |
| Shooters World Match Rifle | <<locked>> | 80% | 47,718 psi | 79% | 2552 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 43,178 psi | 72% | 2470 fps | 100% |
| Shooters World SW4350 | <<locked>> | 84% | 38,159 psi | 63% | 2405 fps | 95.4% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 39,334 psi | 65% | 2464 fps | 99.1% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 48,646 psi | 81% | 2572 fps | 99.3% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 46,659 psi | 78% | 2549 fps | 99.9% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 48,298 psi | 80% | 2470 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 40,437 psi | 67% | 2349 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 84% | 39,508 psi | 66% | 2372 fps | 95.6% |
| SNPE Vectan Tubal 8000 | <<locked>> | 96% | 43,859 psi | 73% | 2579 fps | 95.2% |
| Somchem S335 | <<locked>> | 80% | 48,080 psi | 80% | 2474 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 48,298 psi | 80% | 2562 fps | 99.9% |
| Somchem S355 | <<locked>> | 80% | 39,160 psi | 65% | 2418 fps | 99.4% |
| Somchem S365 | <<locked>> | 80% | 28,718 psi | 48% | 2277 fps | 98.1% |
| Somchem S385 | <<locked>> | 94% | 42,235 psi | 70% | 2516 fps | 95.7% |
| Vihtavuori N133 | <<locked>> | 80% | 48,718 psi | 81% | 2457 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 44,686 psi | 74% | 2454 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 45,281 psi | 75% | 2470 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 37,318 psi | 62% | 2359 fps | 99.7% |
| Vihtavuori N160 | <<locked>> | 80% | 33,359 psi | 55% | 2323 fps | 96.4% |
| Vihtavuori N530 | <<locked>> | 80% | 50,357 psi | 84% | 2572 fps | 100% |
| Vihtavuori N540 | <<locked>> | 80% | 43,453 psi | 72% | 2461 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 32,706 psi | 54% | 2320 fps | 95.9% |
| Vihtavuori N555 | <<locked>> | 84% | 28,094 psi | 47% | 2267 fps | 95.1% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 32,735 psi | 54% | 2293 fps | 98.3% |
| Winchester 748 | <<locked>> | 80% | 50,589 psi | 84% | 2618 fps | 100% |
| Winchester 760 | <<locked>> | 84% | 38,638 psi | 64% | 2467 fps | 95.4% |
| Winchester StaBALL HD | <<locked>> | 88% | 26,136 psi | 43% | 2270 fps | 95.3% |
| Winchester StaBALL Match | <<locked>> | 80% | 46,427 psi | 77% | 2556 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 98% | 44,889 psi | 75% | 2556 fps | 95.1% |
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 98 powders for .260 Rem. loaded with the .263 | 139gr | Prvi Partizan FMJ BT. Alliant Power Pro 2000-MR delivers the highest muzzle velocity at 2,792 fps; across all powders the maximum-charge window runs from 1,627 fps to 2,792 fps. Accurate 3100 gives the best case fill at 100 %, and 98 of the 98 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (415 MPa), the top charges use 60–90 %, leaving at least 10 % headroom. The 139.0 gr projectile in 0.263" calls for a 1:10.0 twist; slower twists will usually not stabilise this weight. Accurate 3100, ADI AR 2209, Alliant Power Pro Varmint 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 70, Alliant Reloder-16, Hodgdon Superformance rank at the top here: for .260 Rem. with the .263 | 139gr | Prvi Partizan FMJ BT 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.