Load Specifications
Load data in caliber .270 Win. with .277 | 130gr | Swift Scirocco 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, Hodgdon Superformance and Alliant Reloder-17.
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>> | 82% | 53,664 psi | 86% | 2805 fps | 100% |
| Accurate 2495 | <<locked>> | 88% | 56,347 psi | 90% | 2881 fps | 100% |
| Accurate 2520 | <<locked>> | 82% | 54,244 psi | 87% | 2894 fps | 100% |
| Accurate 2700 | <<locked>> | 88% | 55,143 psi | 88% | 2877 fps | 97% |
| Accurate 3100ᴾ | <<locked>> | 100% | 43,279 psi | 69% | 2769 fps | 96.3% |
| Accurate 4064 | <<locked>> | 90% | 56,159 psi | 90% | 2927 fps | 100% |
| Accurate 4350 | <<locked>> | 98% | 56,304 psi | 90% | 3015 fps | 99.7% |
| ADI AR 2206H | <<locked>> | 86% | 56,231 psi | 90% | 2956 fps | 100% |
| ADI AR 2208 | <<locked>> | 90% | 54,085 psi | 87% | 2907 fps | 99.7% |
| ADI Benchmark 8208 | <<locked>> | 84% | 55,085 psi | 88% | 2904 fps | 100% |
| Alliant AR-Comp | <<locked>> | 82% | 52,721 psi | 85% | 2835 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 88% | 56,188 psi | 90% | 3081 fps | 99.9% |
| Alliant Reloder- TS 15.5 | <<locked>> | 90% | 54,128 psi | 87% | 2930 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 88% | 54,563 psi | 87% | 2949 fps | 99.8% |
| Alliant Reloder-16 | <<locked>> | 98% | 53,664 psi | 86% | 3015 fps | 99.7% |
| Alliant Reloder-17 | <<locked>> | 94% | 54,897 psi | 88% | 3054 fps | 100% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 41,075 psi | 66% | 2799 fps | 99.1% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 46,427 psi | 74% | 2972 fps | 98.5% |
| Baschieri & Pellagri 107 | <<locked>> | 86% | 56,347 psi | 90% | 2976 fps | 99.8% |
| Bofors RP3 | <<locked>> | 90% | 54,694 psi | 88% | 2946 fps | 100% |
| Bofors RP7 | <<locked>> | 94% | 54,665 psi | 88% | 2913 fps | 97.2% |
| Hodgdon Benchmark | <<locked>> | 82% | 53,519 psi | 86% | 2838 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 84% | 54,737 psi | 88% | 2936 fps | 100% |
| Hodgdon H380 | <<locked>> | 90% | 55,448 psi | 89% | 2956 fps | 99.4% |
| Hodgdon H414 | <<locked>> | 96% | 55,405 psi | 89% | 3009 fps | 98% |
| Hodgdon H4350 | <<locked>> | 94% | 55,825 psi | 90% | 2969 fps | 96.8% |
| Hodgdon H4895 | <<locked>> | 84% | 53,316 psi | 85% | 2913 fps | 100% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 53,490 psi | 86% | 2940 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 86% | 52,953 psi | 85% | 2949 fps | 100% |
| Hodgdon Superformance | <<locked>> | 96% | 56,072 psi | 90% | 3048 fps | 97.7% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 35,592 psi | 57% | 1808 fps | 100% |
| Hodgdon VARGET | <<locked>> | 86% | 54,694 psi | 88% | 2920 fps | 100% |
| IMR 3031 | <<locked>> | 84% | 53,476 psi | 86% | 2900 fps | 100% |
| IMR 4064 | <<locked>> | 88% | 53,417 psi | 86% | 2890 fps | 99.8% |
| IMR 4166 Enduron | <<locked>> | 86% | 53,301 psi | 85% | 2864 fps | 97.5% |
| IMR 4350 | <<locked>> | 98% | 54,969 psi | 88% | 2940 fps | 97.3% |
| IMR 4451 Enduron | <<locked>> | 94% | 56,391 psi | 90% | 2943 fps | 97.9% |
| IMR 4831 | <<locked>> | 98% | 53,243 psi | 85% | 2953 fps | 99.5% |
| IMR 4895 | <<locked>> | 88% | 55,970 psi | 90% | 2982 fps | 100% |
| IMR 8208 XBR | <<locked>> | 84% | 55,085 psi | 88% | 2904 fps | 100% |
| Lovex D073.6 | <<locked>> | 86% | 56,188 psi | 90% | 2933 fps | 100% |
| Lovex S060 | <<locked>> | 86% | 55,782 psi | 89% | 2884 fps | 100% |
| Lovex S062 | <<locked>> | 88% | 53,345 psi | 86% | 2884 fps | 100% |
| Lovex S065 | <<locked>> | 96% | 56,043 psi | 90% | 2940 fps | 99% |
| Lovex S070 | <<locked>> | 96% | 53,737 psi | 86% | 2923 fps | 97.8% |
| Norma 201 | <<locked>> | 86% | 55,013 psi | 88% | 2900 fps | 100% |
| Norma 202 | <<locked>> | 86% | 55,724 psi | 89% | 2904 fps | 100% |
| Norma 203B | <<locked>> | 88% | 53,809 psi | 86% | 2936 fps | 99.9% |
| Norma 204 | <<locked>> | 98% | 55,637 psi | 89% | 2986 fps | 96.1% |
| Norma URP | <<locked>> | 98% | 55,042 psi | 88% | 2999 fps | 99.6% |
| Ramshot Big Game | <<locked>> | 88% | 54,360 psi | 87% | 2963 fps | 99.9% |
| Ramshot Hunter | <<locked>> | 98% | 53,824 psi | 86% | 2992 fps | 98.5% |
| Ramshot TAC | <<locked>> | 84% | 55,477 psi | 89% | 2927 fps | 99% |
| Ramshot Wild Boar | <<locked>> | 84% | 55,361 psi | 89% | 2946 fps | 100% |
| Ramshot X-Terminator | <<locked>> | 82% | 55,825 psi | 90% | 2907 fps | 99.9% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 36,216 psi | 58% | 1854 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 90% | 55,666 psi | 89% | 2936 fps | 98.4% |
| ReloadSwiss RS 52 | <<locked>> | 86% | 54,969 psi | 88% | 3015 fps | 99.8% |
| ReloadSwiss RS 60 | <<locked>> | 92% | 54,665 psi | 88% | 3054 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 98% | 56,246 psi | 90% | 3038 fps | 99.6% |
| ReloadSwiss RS 70 | <<locked>> | 98% | 55,535 psi | 89% | 3068 fps | 99.5% |
| Rottweil R 901 | <<locked>> | 84% | 56,086 psi | 90% | 2884 fps | 100% |
| Rottweil R 902 | <<locked>> | 88% | 55,608 psi | 89% | 2900 fps | 100% |
| Rottweil R 903 | <<locked>> | 92% | 54,578 psi | 88% | 2936 fps | 100% |
| Rottweil R 907 | <<locked>> | 94% | 54,665 psi | 88% | 2913 fps | 97.2% |
| Shooters World Long Rifle | <<locked>> | 96% | 56,043 psi | 90% | 2940 fps | 99% |
| Shooters World Match Rifle | <<locked>> | 86% | 56,188 psi | 90% | 2933 fps | 100% |
| Shooters World Precision | <<locked>> | 88% | 53,345 psi | 86% | 2884 fps | 100% |
| Shooters World SW4350 | <<locked>> | 96% | 53,737 psi | 86% | 2923 fps | 97.8% |
| SNPE Vectan SP 11 | <<locked>> | 92% | 56,405 psi | 90% | 2999 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 84% | 54,172 psi | 87% | 2907 fps | 99.2% |
| SNPE Vectan SP 9 | <<locked>> | 86% | 54,636 psi | 88% | 2927 fps | 99.9% |
| SNPE Vectan Tubal 3000 | <<locked>> | 86% | 56,420 psi | 90% | 2838 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 90% | 53,258 psi | 85% | 2789 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 96% | 56,231 psi | 90% | 2890 fps | 98% |
| Somchem S321 | <<locked>> | 82% | 56,420 psi | 90% | 2936 fps | 100% |
| Somchem S335 | <<locked>> | 86% | 55,782 psi | 89% | 2835 fps | 100% |
| Somchem S341 | <<locked>> | 84% | 53,621 psi | 86% | 2894 fps | 99.9% |
| Somchem S355 | <<locked>> | 92% | 54,926 psi | 88% | 2936 fps | 100% |
| Somchem S365ᴾ | <<locked>> | 100% | 53,243 psi | 85% | 3002 fps | 100% |
| Somchem S385ᴾ | <<locked>> | 100% | 49,472 psi | 79% | 2877 fps | 96.1% |
| Vihtavuori N130 | <<locked>> | 82% | 55,912 psi | 90% | 2795 fps | 100% |
| Vihtavuori N133 | <<locked>> | 84% | 53,461 psi | 86% | 2779 fps | 100% |
| Vihtavuori N135 | <<locked>> | 88% | 55,390 psi | 89% | 2864 fps | 100% |
| Vihtavuori N140 | <<locked>> | 88% | 56,231 psi | 90% | 2881 fps | 100% |
| Vihtavuori N150 | <<locked>> | 94% | 56,347 psi | 90% | 2910 fps | 100% |
| Vihtavuori N160 | <<locked>> | 96% | 53,969 psi | 87% | 2943 fps | 99.4% |
| Vihtavuori N530 | <<locked>> | 84% | 55,608 psi | 89% | 2907 fps | 100% |
| Vihtavuori N540 | <<locked>> | 88% | 54,230 psi | 87% | 2874 fps | 100% |
| Vihtavuori N550 | <<locked>> | 96% | 53,301 psi | 85% | 2949 fps | 99.3% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 45,324 psi | 73% | 2877 fps | 99% |
| Winchester 6.5 StaBALL | <<locked>> | 96% | 54,273 psi | 87% | 2920 fps | 100% |
| Winchester 748 | <<locked>> | 84% | 55,956 psi | 90% | 2956 fps | 100% |
| Winchester 760 | <<locked>> | 96% | 55,405 psi | 89% | 3009 fps | 98% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 36,999 psi | 59% | 2808 fps | 99.1% |
| Winchester StaBALL Match | <<locked>> | 86% | 54,839 psi | 88% | 2940 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% | 50,560 psi | 81% | 2759 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 43,236 psi | 69% | 2680 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 50,488 psi | 81% | 2838 fps | 100% |
| Accurate 2700 | <<locked>> | 84% | 48,254 psi | 77% | 2762 fps | 95.5% |
| Accurate 3100 | <<locked>> | 98% | 40,335 psi | 65% | 2710 fps | 95.5% |
| Accurate 4064 | <<locked>> | 80% | 40,915 psi | 66% | 2677 fps | 100% |
| Accurate 4350 | <<locked>> | 84% | 34,577 psi | 55% | 2602 fps | 95.4% |
| ADI AR 2206H | <<locked>> | 80% | 46,702 psi | 75% | 2795 fps | 99.4% |
| ADI AR 2208 | <<locked>> | 80% | 39,624 psi | 64% | 2638 fps | 97.6% |
| ADI Benchmark 8208 | <<locked>> | 80% | 48,747 psi | 78% | 2802 fps | 99.9% |
| Alliant AR-Comp | <<locked>> | 80% | 49,501 psi | 79% | 2789 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 42,598 psi | 68% | 2828 fps | 98.3% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 39,508 psi | 63% | 2664 fps | 98.9% |
| Alliant Reloder-15 | <<locked>> | 80% | 42,337 psi | 68% | 2730 fps | 98.4% |
| Alliant Reloder-16 | <<locked>> | 84% | 34,795 psi | 56% | 2618 fps | 95.5% |
| Alliant Reloder-17 | 45.4 gr | 80% | 34,142 psi | 55% | 2631 fps | 97.2% |
| Alliant Reloder-23 | <<locked>> | 90% | 30,081 psi | 48% | 2516 fps | 95.2% |
| Alliant Reloder-26 | <<locked>> | 94% | 37,449 psi | 60% | 2769 fps | 95.8% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 46,035 psi | 74% | 2802 fps | 98.6% |
| Bofors RP3 | <<locked>> | 80% | 39,102 psi | 63% | 2667 fps | 98.9% |
| Bofors RP7 | <<locked>> | 88% | 45,310 psi | 73% | 2746 fps | 95% |
| Hodgdon Benchmark | <<locked>> | 80% | 50,241 psi | 81% | 2789 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 80% | 47,819 psi | 77% | 2825 fps | 100% |
| Hodgdon H380 | <<locked>> | 80% | 39,914 psi | 64% | 2671 fps | 96.6% |
| Hodgdon H414 | <<locked>> | 90% | 45,469 psi | 73% | 2835 fps | 95.9% |
| Hodgdon H4350 | <<locked>> | 90% | 49,139 psi | 79% | 2858 fps | 95.3% |
| Hodgdon H4895 | <<locked>> | 80% | 47,137 psi | 76% | 2808 fps | 99.7% |
| Hodgdon Hybrid 100V | <<locked>> | 82% | 29,936 psi | 48% | 2457 fps | 95.4% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 43,163 psi | 69% | 2776 fps | 99.5% |
| Hodgdon Superformance | 54 gr | 90% | 45,208 psi | 72% | 2851 fps | 95.1% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,614 psi | 43% | 1617 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 45,020 psi | 72% | 2753 fps | 99.4% |
| IMR 3031 | <<locked>> | 80% | 46,891 psi | 75% | 2799 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 41,626 psi | 67% | 2674 fps | 98.3% |
| IMR 4166 Enduron | <<locked>> | 80% | 44,063 psi | 71% | 2697 fps | 95.3% |
| IMR 4350 | <<locked>> | 92% | 45,629 psi | 73% | 2776 fps | 95.2% |
| IMR 4451 Enduron | <<locked>> | 86% | 44,353 psi | 71% | 2730 fps | 95.3% |
| IMR 4831 | <<locked>> | 84% | 33,518 psi | 54% | 2559 fps | 95.1% |
| IMR 4895 | <<locked>> | 80% | 43,395 psi | 70% | 2762 fps | 99% |
| IMR 8208 XBR | <<locked>> | 80% | 48,747 psi | 78% | 2802 fps | 99.9% |
| Lovex D073.6 | <<locked>> | 80% | 46,050 psi | 74% | 2772 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 46,412 psi | 74% | 2730 fps | 99.4% |
| Lovex S062 | <<locked>> | 80% | 41,655 psi | 67% | 2680 fps | 99.4% |
| Lovex S065 | <<locked>> | 84% | 38,899 psi | 62% | 2621 fps | 95.3% |
| Lovex S070 | <<locked>> | 88% | 41,829 psi | 67% | 2703 fps | 95% |
| Norma 201 | <<locked>> | 80% | 45,585 psi | 73% | 2743 fps | 99.8% |
| Norma 202 | <<locked>> | 80% | 46,122 psi | 74% | 2753 fps | 100% |
| Norma 203B | <<locked>> | 80% | 41,727 psi | 67% | 2720 fps | 98.7% |
| Norma 204 | <<locked>> | 96% | 52,011 psi | 83% | 2930 fps | 95.3% |
| Norma URP | <<locked>> | 84% | 34,809 psi | 56% | 2605 fps | 95.3% |
| Ramshot Big Game | <<locked>> | 80% | 41,336 psi | 66% | 2730 fps | 98.5% |
| Ramshot Hunter | <<locked>> | 90% | 41,539 psi | 67% | 2762 fps | 95.7% |
| Ramshot TAC | <<locked>> | 80% | 48,747 psi | 78% | 2812 fps | 98% |
| Ramshot Wild Boar | <<locked>> | 80% | 48,182 psi | 77% | 2828 fps | 99.5% |
| Ramshot X-Terminator | <<locked>> | 80% | 52,504 psi | 84% | 2854 fps | 99.8% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,021 psi | 43% | 1657 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 82% | 42,946 psi | 69% | 2707 fps | 95.7% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 44,846 psi | 72% | 2838 fps | 98.8% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 36,318 psi | 58% | 2700 fps | 99.6% |
| ReloadSwiss RS 62 | <<locked>> | 86% | 36,753 psi | 59% | 2677 fps | 95.8% |
| ReloadSwiss RS 70 | 50.7 gr | 88% | 39,320 psi | 63% | 2746 fps | 95.9% |
| Rottweil R 901 | <<locked>> | 80% | 49,661 psi | 80% | 2785 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 43,395 psi | 70% | 2697 fps | 99.6% |
| Rottweil R 903 | <<locked>> | 80% | 36,883 psi | 59% | 2612 fps | 98.2% |
| Rottweil R 907 | <<locked>> | 88% | 45,310 psi | 73% | 2746 fps | 95% |
| Shooters World Long Rifle | <<locked>> | 84% | 38,899 psi | 62% | 2621 fps | 95.3% |
| Shooters World Match Rifle | <<locked>> | 80% | 46,050 psi | 74% | 2772 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 41,655 psi | 67% | 2680 fps | 99.4% |
| Shooters World SW4350 | <<locked>> | 88% | 41,829 psi | 67% | 2703 fps | 95% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 37,855 psi | 61% | 2661 fps | 97.7% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 47,021 psi | 75% | 2782 fps | 98.1% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 45,121 psi | 72% | 2762 fps | 99.2% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 46,804 psi | 75% | 2694 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 39,088 psi | 63% | 2556 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 88% | 43,395 psi | 70% | 2671 fps | 95.2% |
| Somchem S321 | <<locked>> | 80% | 52,939 psi | 85% | 2887 fps | 100% |
| Somchem S335 | <<locked>> | 80% | 46,441 psi | 74% | 2694 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 46,905 psi | 75% | 2782 fps | 99.4% |
| Somchem S355 | <<locked>> | 80% | 37,579 psi | 60% | 2615 fps | 98.2% |
| Somchem S365 | <<locked>> | 80% | 27,369 psi | 44% | 2438 fps | 95.7% |
| Somchem S385 | <<locked>> | 98% | 46,325 psi | 74% | 2822 fps | 95.3% |
| Vihtavuori N130 | <<locked>> | 80% | 52,707 psi | 85% | 2753 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 47,195 psi | 76% | 2684 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 43,062 psi | 69% | 2674 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 43,584 psi | 70% | 2684 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 35,824 psi | 57% | 2549 fps | 98.8% |
| Vihtavuori N160 | <<locked>> | 82% | 34,185 psi | 55% | 2556 fps | 95% |
| Vihtavuori N530 | <<locked>> | 80% | 48,718 psi | 78% | 2795 fps | 100% |
| Vihtavuori N540 | <<locked>> | 80% | 42,032 psi | 67% | 2674 fps | 100% |
| Vihtavuori N550 | <<locked>> | 84% | 35,853 psi | 57% | 2608 fps | 95.4% |
| Vihtavuori N555 | <<locked>> | 90% | 32,532 psi | 52% | 2595 fps | 95.4% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 31,778 psi | 51% | 2474 fps | 96.5% |
| Winchester 748 | <<locked>> | 80% | 48,791 psi | 78% | 2844 fps | 100% |
| Winchester 760 | <<locked>> | 88% | 42,569 psi | 68% | 2776 fps | 95% |
| Winchester StaBALL HD | <<locked>> | 94% | 30,356 psi | 49% | 2602 fps | 95.9% |
| Winchester StaBALL Match | <<locked>> | 80% | 44,643 psi | 72% | 2766 fps | 99.5% |
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 .270 Win. loaded with the .277 | 130gr | Swift Scirocco. Alliant Power Pro 2000-MR delivers the highest muzzle velocity at 3,081 fps; across all powders the maximum-charge window runs from 1,808 fps to 3,081 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 57–90 %, leaving at least 10 % headroom. The 130.0 gr projectile in 0.277" calls for a 1:9.5 twist; slower twists will usually not stabilise this weight. Accurate 3100, Alliant Reloder-23, Alliant Reloder-26 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, Hodgdon Superformance, Alliant Reloder-17 rank at the top here: for .270 Win. with the .277 | 130gr | Swift Scirocco 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.