Load Specifications
Load data in caliber .270 Win. with .277 | 150gr | Woodleigh PP SN 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 70, Alliant Reloder-26 and Alliant Reloder-16.
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.
A valid access license is required to use the Personalized Load Calculator.
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% | 53,243 psi | 85% | 2644 fps | 100% |
| Accurate 2700 | <<locked>> | 88% | 55,753 psi | 89% | 2717 fps | 98.7% |
| Accurate 3100ᴾ | <<locked>> | 100% | 52,852 psi | 85% | 2741 fps | 99.3% |
| Accurate 4064 | <<locked>> | 84% | 53,650 psi | 86% | 2697 fps | 100% |
| Accurate 4350 | <<locked>> | 92% | 53,896 psi | 86% | 2795 fps | 100% |
| ADI AR 2206H | <<locked>> | 82% | 56,173 psi | 90% | 2770 fps | 100% |
| ADI AR 2208 | <<locked>> | 86% | 53,867 psi | 86% | 2726 fps | 100% |
| ADI AR 2209 | <<locked>> | 98% | 54,839 psi | 88% | 2834 fps | 98% |
| ADI AR 2213ᴾ | <<locked>> | 100% | 53,519 psi | 86% | 2821 fps | 96.2% |
| Alliant Power Pro 2000-MR | <<locked>> | 82% | 52,576 psi | 84% | 2838 fps | 100% |
| Alliant Reloder- TS 15.5 | <<locked>> | 86% | 54,433 psi | 87% | 2748 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 84% | 54,795 psi | 88% | 2769 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 94% | 54,824 psi | 88% | 2851 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 90% | 55,811 psi | 89% | 2873 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 98% | 54,085 psi | 87% | 2822 fps | 97.9% |
| Alliant Reloder-22ᴾ | <<locked>> | 100% | 52,141 psi | 84% | 2820 fps | 97.6% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 48,515 psi | 78% | 2761 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 43,062 psi | 69% | 2682 fps | 98.6% |
| Alliant Reloder-26 | <<locked>> | 98% | 52,852 psi | 85% | 2892 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 82% | 55,898 psi | 90% | 2786 fps | 100% |
| Bofors RP15ᴾ | <<locked>> | 100% | 46,934 psi | 75% | 2746 fps | 96.5% |
| Bofors RP3 | <<locked>> | 86% | 55,216 psi | 89% | 2764 fps | 100% |
| Bofors RP5ᴾ | <<locked>> | 100% | 51,126 psi | 82% | 2818 fps | 97.6% |
| Bofors RP7 | <<locked>> | 90% | 54,752 psi | 88% | 2748 fps | 98.7% |
| Hodgdon H380 | <<locked>> | 86% | 55,579 psi | 89% | 2778 fps | 100% |
| Hodgdon H414 | <<locked>> | 88% | 53,853 psi | 86% | 2811 fps | 99.1% |
| Hodgdon H4350 | <<locked>> | 92% | 54,462 psi | 87% | 2779 fps | 98.2% |
| Hodgdon Hybrid 100V | <<locked>> | 96% | 54,984 psi | 88% | 2775 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 84% | 53,548 psi | 86% | 2769 fps | 100% |
| Hodgdon Superformance | <<locked>> | 92% | 56,289 psi | 90% | 2883 fps | 99.2% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 37,130 psi | 60% | 1702 fps | 100% |
| Hodgdon VARGET | <<locked>> | 84% | 53,534 psi | 86% | 2720 fps | 100% |
| IMR 3031 | <<locked>> | 84% | 55,883 psi | 90% | 2733 fps | 100% |
| IMR 4064 | <<locked>> | 88% | 56,086 psi | 90% | 2746 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 88% | 54,911 psi | 88% | 2727 fps | 99.1% |
| IMR 4350 | <<locked>> | 94% | 55,405 psi | 89% | 2779 fps | 98.9% |
| IMR 4451 Enduron | <<locked>> | 90% | 56,362 psi | 90% | 2772 fps | 99.2% |
| IMR 4831 | <<locked>> | 98% | 55,071 psi | 88% | 2798 fps | 100% |
| IMR 4895 | <<locked>> | 84% | 56,202 psi | 90% | 2797 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 98% | 54,433 psi | 87% | 2762 fps | 96.2% |
| IMR 7828 SSCᴾ | <<locked>> | 100% | 54,737 psi | 88% | 2859 fps | 96.6% |
| Lovex S060 | <<locked>> | 82% | 54,824 psi | 88% | 2693 fps | 100% |
| Lovex S062 | <<locked>> | 84% | 53,417 psi | 86% | 2703 fps | 100% |
| Lovex S065 | <<locked>> | 92% | 56,318 psi | 90% | 2770 fps | 99.8% |
| Lovex S070 | <<locked>> | 92% | 54,273 psi | 87% | 2762 fps | 99.2% |
| Lovex S071ᴾ | <<locked>> | 100% | 43,424 psi | 70% | 2597 fps | 98% |
| Norma 201 | <<locked>> | 82% | 54,882 psi | 88% | 2713 fps | 100% |
| Norma 202 | <<locked>> | 82% | 55,390 psi | 89% | 2709 fps | 100% |
| Norma 203B | <<locked>> | 84% | 54,056 psi | 87% | 2755 fps | 100% |
| Norma 204 | <<locked>> | 94% | 56,217 psi | 90% | 2830 fps | 98% |
| Norma MRPᴾ | <<locked>> | 100% | 54,273 psi | 87% | 2902 fps | 99.2% |
| Norma URP | <<locked>> | 94% | 56,072 psi | 90% | 2829 fps | 100% |
| Ramshot Big Game | <<locked>> | 84% | 54,578 psi | 88% | 2781 fps | 100% |
| Ramshot Grand | <<locked>> | 98% | 53,534 psi | 86% | 2864 fps | 96.9% |
| Ramshot Hunter | <<locked>> | 94% | 54,926 psi | 88% | 2833 fps | 99.6% |
| Ramshot Magnumᴾ | <<locked>> | 100% | 51,706 psi | 83% | 2785 fps | 97.9% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 37,188 psi | 60% | 1745 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 86% | 55,622 psi | 89% | 2765 fps | 99.5% |
| ReloadSwiss RS 52 | <<locked>> | 82% | 55,724 psi | 89% | 2837 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 88% | 55,579 psi | 89% | 2869 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 92% | 53,534 psi | 86% | 2816 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 94% | 55,970 psi | 90% | 2900 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 41,829 psi | 67% | 2690 fps | 96.3% |
| Rottweil R 902 | <<locked>> | 84% | 55,434 psi | 89% | 2713 fps | 100% |
| Rottweil R 903 | <<locked>> | 88% | 55,419 psi | 89% | 2762 fps | 100% |
| Rottweil R 904 | <<locked>> | 96% | 53,330 psi | 86% | 2754 fps | 96.6% |
| Rottweil R 905 | <<locked>> | 98% | 53,287 psi | 85% | 2807 fps | 97.9% |
| Rottweil R 907 | <<locked>> | 90% | 54,752 psi | 88% | 2748 fps | 98.7% |
| Shooters World Long Rifle | <<locked>> | 92% | 56,318 psi | 90% | 2770 fps | 99.8% |
| Shooters World Precision | <<locked>> | 84% | 53,417 psi | 86% | 2703 fps | 100% |
| Shooters World SW4350 | <<locked>> | 92% | 54,273 psi | 87% | 2762 fps | 99.2% |
| SNPE Vectan SP 11 | <<locked>> | 86% | 53,156 psi | 85% | 2765 fps | 100% |
| SNPE Vectan SP 9 | <<locked>> | 82% | 54,621 psi | 88% | 2744 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 82% | 55,666 psi | 89% | 2645 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 88% | 56,333 psi | 90% | 2646 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 92% | 56,115 psi | 90% | 2724 fps | 99.2% |
| SNPE Vectan Tubal 8000ᴾ | <<locked>> | 100% | 56,420 psi | 90% | 2858 fps | 98.4% |
| Somchem S335 | <<locked>> | 82% | 55,405 psi | 89% | 2644 fps | 100% |
| Somchem S355 | <<locked>> | 88% | 55,158 psi | 88% | 2753 fps | 100% |
| Somchem S361 | <<locked>> | 96% | 54,998 psi | 88% | 2748 fps | 96% |
| Somchem S365 | <<locked>> | 96% | 55,216 psi | 89% | 2832 fps | 100% |
| Somchem S385 | <<locked>> | 98% | 53,954 psi | 87% | 2785 fps | 98.6% |
| Unknown powder | <<locked>> | 90% | 53,388 psi | 86% | 2785 fps | 99.8% |
| Vihtavuori N133 | <<locked>> | 84% | 55,651 psi | 89% | 2624 fps | 100% |
| Vihtavuori N135 | <<locked>> | 84% | 55,883 psi | 90% | 2674 fps | 100% |
| Vihtavuori N140 | <<locked>> | 84% | 55,376 psi | 89% | 2684 fps | 100% |
| Vihtavuori N150 | <<locked>> | 92% | 53,345 psi | 86% | 2690 fps | 100% |
| Vihtavuori N160 | <<locked>> | 90% | 53,722 psi | 86% | 2755 fps | 100% |
| Vihtavuori N165ᴾ | <<locked>> | 100% | 49,371 psi | 79% | 2677 fps | 97.2% |
| Vihtavuori N540 | <<locked>> | 84% | 54,969 psi | 88% | 2709 fps | 100% |
| Vihtavuori N550 | <<locked>> | 90% | 54,288 psi | 87% | 2803 fps | 100% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 54,621 psi | 88% | 2835 fps | 100% |
| Winchester 6.5 StaBALL | <<locked>> | 92% | 54,505 psi | 87% | 2746 fps | 100% |
| Winchester 760 | <<locked>> | 88% | 53,853 psi | 86% | 2811 fps | 99.1% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 44,570 psi | 71% | 2810 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 96% | 52,170 psi | 84% | 2750 fps | 97.4% |
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% | 49,879 psi | 80% | 2595 fps | 100% |
| Accurate 2700 | <<locked>> | 80% | 43,004 psi | 69% | 2503 fps | 96.2% |
| Accurate 3100 | <<locked>> | 88% | 34,316 psi | 55% | 2422 fps | 95.5% |
| Accurate 4064 | <<locked>> | 80% | 47,268 psi | 76% | 2602 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 35,810 psi | 57% | 2467 fps | 97.7% |
| ADI AR 2206H | <<locked>> | 80% | 52,750 psi | 85% | 2721 fps | 100% |
| ADI AR 2208 | <<locked>> | 80% | 44,860 psi | 72% | 2577 fps | 99.6% |
| ADI AR 2209 | <<locked>> | 92% | 45,150 psi | 72% | 2664 fps | 95.8% |
| ADI AR 2213 | <<locked>> | 98% | 49,153 psi | 79% | 2763 fps | 95.3% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 49,197 psi | 79% | 2783 fps | 100% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 45,005 psi | 72% | 2599 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 80% | 48,298 psi | 77% | 2668 fps | 99.9% |
| Alliant Reloder-16 | 43.1 gr | 80% | 35,070 psi | 56% | 2477 fps | 97.8% |
| Alliant Reloder-17 | <<locked>> | 80% | 39,479 psi | 63% | 2597 fps | 99.8% |
| Alliant Reloder-19 | <<locked>> | 90% | 41,959 psi | 67% | 2603 fps | 95% |
| Alliant Reloder-22 | <<locked>> | 94% | 42,090 psi | 67% | 2652 fps | 95.2% |
| Alliant Reloder-23 | <<locked>> | 80% | 25,657 psi | 41% | 2238 fps | 95.1% |
| Alliant Reloder-25 | <<locked>> | 92% | 32,808 psi | 53% | 2455 fps | 95.1% |
| Alliant Reloder-26 | 50 gr | 84% | 31,241 psi | 50% | 2458 fps | 95.5% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 52,272 psi | 84% | 2733 fps | 100% |
| Bofors RP15 | <<locked>> | 98% | 43,990 psi | 71% | 2687 fps | 95.6% |
| Bofors RP3 | <<locked>> | 80% | 45,179 psi | 72% | 2608 fps | 100% |
| Bofors RP5 | <<locked>> | 94% | 42,090 psi | 67% | 2651 fps | 95.2% |
| Bofors RP7 | <<locked>> | 80% | 39,958 psi | 64% | 2483 fps | 95.6% |
| Hodgdon H380 | <<locked>> | 80% | 45,687 psi | 73% | 2619 fps | 99.2% |
| Hodgdon H414 | <<locked>> | 80% | 40,959 psi | 66% | 2581 fps | 96.6% |
| Hodgdon H4350 | <<locked>> | 84% | 42,554 psi | 68% | 2569 fps | 95.5% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 32,547 psi | 52% | 2376 fps | 98.4% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 46,891 psi | 75% | 2664 fps | 100% |
| Hodgdon Superformance | <<locked>> | 82% | 39,392 psi | 63% | 2577 fps | 95.6% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,079 psi | 43% | 1521 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 47,152 psi | 76% | 2618 fps | 100% |
| IMR 3031 | <<locked>> | 80% | 49,530 psi | 79% | 2644 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 43,961 psi | 70% | 2552 fps | 99.7% |
| IMR 4166 Enduron | <<locked>> | 80% | 43,294 psi | 69% | 2526 fps | 97.1% |
| IMR 4350 | <<locked>> | 84% | 40,538 psi | 65% | 2516 fps | 95.8% |
| IMR 4451 Enduron | <<locked>> | 80% | 41,379 psi | 66% | 2513 fps | 96.5% |
| IMR 4831 | <<locked>> | 80% | 31,328 psi | 50% | 2346 fps | 96.2% |
| IMR 4895 | <<locked>> | 80% | 49,545 psi | 79% | 2694 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 96% | 51,140 psi | 82% | 2710 fps | 95.5% |
| IMR 7828 SSC | <<locked>> | 98% | 51,735 psi | 83% | 2800 fps | 95.8% |
| Lovex S060 | <<locked>> | 80% | 51,822 psi | 83% | 2648 fps | 100% |
| Lovex S062 | <<locked>> | 80% | 47,369 psi | 76% | 2609 fps | 100% |
| Lovex S065 | <<locked>> | 80% | 39,015 psi | 63% | 2468 fps | 97.3% |
| Lovex S070 | <<locked>> | 80% | 37,289 psi | 60% | 2448 fps | 95.6% |
| Lovex S071 | <<locked>> | 94% | 35,360 psi | 57% | 2445 fps | 95.8% |
| Norma 201 | <<locked>> | 80% | 51,503 psi | 83% | 2664 fps | 100% |
| Norma 202 | <<locked>> | 80% | 51,967 psi | 83% | 2661 fps | 100% |
| Norma 203B | <<locked>> | 80% | 47,674 psi | 76% | 2654 fps | 100% |
| Norma 204 | <<locked>> | 86% | 42,859 psi | 69% | 2601 fps | 95% |
| Norma MRP | <<locked>> | 90% | 38,653 psi | 62% | 2608 fps | 95.6% |
| Norma URP | <<locked>> | 80% | 35,708 psi | 57% | 2464 fps | 97.6% |
| Ramshot Big Game | <<locked>> | 80% | 47,834 psi | 77% | 2677 fps | 100% |
| Ramshot Grand | <<locked>> | 94% | 46,412 psi | 74% | 2737 fps | 95% |
| Ramshot Hunter | <<locked>> | 80% | 34,563 psi | 55% | 2448 fps | 95.3% |
| Ramshot Magnum | <<locked>> | 94% | 39,958 psi | 64% | 2589 fps | 95.1% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,601 psi | 44% | 1558 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 45,716 psi | 73% | 2601 fps | 98.2% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 51,924 psi | 83% | 2780 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 41,974 psi | 67% | 2651 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 35,462 psi | 57% | 2484 fps | 97.3% |
| ReloadSwiss RS 70 | 47.2 gr | 80% | 34,722 psi | 56% | 2489 fps | 96.5% |
| ReloadSwiss RS 76 | <<locked>> | 98% | 38,218 psi | 61% | 2623 fps | 95.1% |
| Rottweil R 902 | <<locked>> | 80% | 49,139 psi | 79% | 2620 fps | 100% |
| Rottweil R 903 | <<locked>> | 80% | 42,714 psi | 68% | 2560 fps | 99.9% |
| Rottweil R 904 | <<locked>> | 92% | 46,920 psi | 75% | 2645 fps | 95% |
| Rottweil R 905 | <<locked>> | 92% | 43,700 psi | 70% | 2641 fps | 95.8% |
| Rottweil R 907 | <<locked>> | 80% | 39,958 psi | 64% | 2483 fps | 95.6% |
| Shooters World Long Rifle | <<locked>> | 80% | 39,015 psi | 63% | 2468 fps | 97.3% |
| Shooters World Precision | <<locked>> | 80% | 47,369 psi | 76% | 2609 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 37,289 psi | 60% | 2448 fps | 95.6% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 43,671 psi | 70% | 2609 fps | 99.8% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 51,097 psi | 82% | 2691 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 52,518 psi | 84% | 2602 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 44,324 psi | 71% | 2477 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 38,247 psi | 61% | 2414 fps | 95.7% |
| SNPE Vectan Tubal 8000 | <<locked>> | 92% | 43,294 psi | 69% | 2635 fps | 95.6% |
| Somchem S335 | <<locked>> | 80% | 52,127 psi | 84% | 2599 fps | 100% |
| Somchem S355 | <<locked>> | 80% | 43,062 psi | 69% | 2558 fps | 99.9% |
| Somchem S361 | <<locked>> | 94% | 51,387 psi | 82% | 2690 fps | 95.2% |
| Somchem S365 | <<locked>> | 80% | 32,097 psi | 51% | 2420 fps | 99.3% |
| Somchem S385 | <<locked>> | 88% | 38,957 psi | 62% | 2516 fps | 95.2% |
| Unknown powder | <<locked>> | 80% | 38,580 psi | 62% | 2518 fps | 97.7% |
| Vihtavuori N133 | <<locked>> | 80% | 49,530 psi | 79% | 2541 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 49,342 psi | 79% | 2585 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 48,776 psi | 78% | 2592 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 37,028 psi | 59% | 2416 fps | 99.8% |
| Vihtavuori N160 | <<locked>> | 80% | 38,638 psi | 62% | 2494 fps | 98.3% |
| Vihtavuori N165 | <<locked>> | 96% | 42,076 psi | 67% | 2571 fps | 95.7% |
| Vihtavuori N540 | <<locked>> | 80% | 48,327 psi | 77% | 2611 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 39,073 psi | 63% | 2533 fps | 98.3% |
| Vihtavuori N555 | <<locked>> | 80% | 28,007 psi | 45% | 2312 fps | 95.3% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 36,216 psi | 58% | 2436 fps | 99.4% |
| Winchester 760 | <<locked>> | 80% | 40,959 psi | 66% | 2581 fps | 96.6% |
| Winchester StaBALL HD | <<locked>> | 84% | 25,715 psi | 41% | 2317 fps | 95.8% |
| Winchester Supreme 780 | <<locked>> | 90% | 42,148 psi | 68% | 2576 fps | 95% |
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 .270 Win. loaded with the .277 | 150gr | Woodleigh PP SN. Norma MRP delivers the highest muzzle velocity at 2,902 fps; across all powders the maximum-charge window runs from 1,702 fps to 2,902 fps. Accurate 3100 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 60–90 %, leaving at least 10 % headroom. The 150.0 gr projectile in 0.277" calls for a 1:11.5 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. ReloadSwiss RS 70, Alliant Reloder-26, Alliant Reloder-16 rank at the top here: for .270 Win. with the .277 | 150gr | Woodleigh PP SN 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.