Load Specifications
Load data in caliber 7 x 66 SE v. Hofe with .284 | 160gr | Winchester FailSafe bullet and 73 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Hodgdon Retumbo, ReloadSwiss RS 76 and Vihtavuori N560.
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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Max Load - Barrel Length: 25.6"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 3100 | <<locked>> | 92% | 55,724 psi | 87% | 2930 fps | 100% |
| Accurate 4350 | <<locked>> | 84% | 56,869 psi | 89% | 2956 fps | 100% |
| Accurate High Country | <<locked>> | 90% | 57,479 psi | 90% | 3094 fps | 99.6% |
| Accurate MAGPRO | <<locked>> | 90% | 54,331 psi | 85% | 3028 fps | 98.5% |
| ADI AR 2209 | <<locked>> | 90% | 57,566 psi | 90% | 3022 fps | 99.9% |
| ADI AR 2213 | <<locked>> | 92% | 55,506 psi | 87% | 3031 fps | 99.4% |
| ADI AR 2217ᴾ | <<locked>> | 100% | 53,388 psi | 84% | 2992 fps | 99.4% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 48,008 psi | 75% | 2956 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 88% | 54,273 psi | 85% | 2966 fps | 99.7% |
| Alliant Reloder-16 | <<locked>> | 84% | 54,143 psi | 85% | 2959 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 90% | 57,101 psi | 89% | 3012 fps | 99.9% |
| Alliant Reloder-22 | <<locked>> | 92% | 55,724 psi | 87% | 3028 fps | 99.9% |
| Alliant Reloder-23 | <<locked>> | 94% | 57,159 psi | 90% | 2989 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 98% | 56,637 psi | 89% | 3058 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 88% | 53,708 psi | 84% | 3025 fps | 100% |
| Baschieri & Pellagri 109 | <<locked>> | 94% | 56,782 psi | 89% | 2992 fps | 97.5% |
| Bofors RP15 | <<locked>> | 94% | 54,926 psi | 86% | 3015 fps | 99.8% |
| Bofors RP30ᴾ | <<locked>> | 100% | 56,550 psi | 89% | 3068 fps | 99.7% |
| Bofors RP5 | <<locked>> | 92% | 55,724 psi | 87% | 3028 fps | 99.9% |
| Bofors RP7 | <<locked>> | 82% | 55,042 psi | 86% | 2904 fps | 100% |
| Hodgdon H1000 | <<locked>> | 98% | 55,143 psi | 86% | 3022 fps | 99.8% |
| Hodgdon H414 | <<locked>> | 82% | 54,636 psi | 86% | 2956 fps | 100% |
| Hodgdon H4350 | <<locked>> | 82% | 56,927 psi | 89% | 2966 fps | 99.9% |
| Hodgdon H4831 | <<locked>> | 90% | 55,216 psi | 87% | 2966 fps | 98.9% |
| Hodgdon H4831 SC | <<locked>> | 90% | 54,041 psi | 85% | 2946 fps | 98.7% |
| Hodgdon Hybrid 100V | <<locked>> | 86% | 54,491 psi | 85% | 2884 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 98% | 55,448 psi | 87% | 3140 fps | 100% |
| Hodgdon Superformance | <<locked>> | 82% | 55,056 psi | 86% | 2992 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 37,405 psi | 59% | 1860 fps | 100% |
| IMR 4350 | <<locked>> | 86% | 56,898 psi | 89% | 2946 fps | 100% |
| IMR 4451 Enduron | <<locked>> | 82% | 56,347 psi | 88% | 2923 fps | 100% |
| IMR 4831 | <<locked>> | 86% | 57,130 psi | 90% | 2946 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 90% | 56,014 psi | 88% | 2946 fps | 99.1% |
| IMR 7828 SSC | <<locked>> | 94% | 57,421 psi | 90% | 3074 fps | 99.6% |
| IMR 8133 Enduronᴾ | <<locked>> | 100% | 43,526 psi | 68% | 2861 fps | 97.8% |
| Lovex S065 | <<locked>> | 84% | 57,232 psi | 90% | 2923 fps | 100% |
| Lovex S070 | <<locked>> | 84% | 55,550 psi | 87% | 2920 fps | 100% |
| Lovex S071 | <<locked>> | 98% | 56,985 psi | 89% | 2946 fps | 100% |
| Norma 204 | <<locked>> | 84% | 54,273 psi | 85% | 2946 fps | 99.6% |
| Norma 217ᴾ | <<locked>> | 100% | 43,845 psi | 69% | 2887 fps | 99.5% |
| Norma MRP | <<locked>> | 90% | 55,695 psi | 87% | 3048 fps | 100% |
| Norma URP | <<locked>> | 84% | 55,143 psi | 86% | 2936 fps | 100% |
| Ramshot Grand | <<locked>> | 92% | 54,302 psi | 85% | 3031 fps | 99.5% |
| Ramshot Hunter | <<locked>> | 86% | 57,696 psi | 90% | 3002 fps | 100% |
| Ramshot Magnum | <<locked>> | 96% | 56,855 psi | 89% | 3022 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 38,276 psi | 60% | 1906 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 84% | 56,971 psi | 89% | 2982 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 84% | 55,274 psi | 87% | 3012 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 98% | 56,478 psi | 89% | 3136 fps | 100% |
| ReloadSwiss RS 80ᴾ | <<locked>> | 100% | 55,637 psi | 87% | 3094 fps | 99% |
| Rottweil R 904 | <<locked>> | 88% | 54,940 psi | 86% | 2933 fps | 99.3% |
| Rottweil R 905 | <<locked>> | 90% | 56,840 psi | 89% | 3002 fps | 99.9% |
| Rottweil R 907 | <<locked>> | 82% | 55,042 psi | 86% | 2904 fps | 100% |
| Shooters World Long Rifle | <<locked>> | 84% | 57,232 psi | 90% | 2923 fps | 100% |
| Shooters World SW4350 | <<locked>> | 84% | 55,550 psi | 87% | 2920 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 84% | 56,260 psi | 88% | 2874 fps | 100% |
| SNPE Vectan Tubal 8000 | <<locked>> | 90% | 56,420 psi | 88% | 2999 fps | 99.9% |
| Somchem S361 | <<locked>> | 88% | 56,478 psi | 89% | 2927 fps | 99% |
| Somchem S365 | <<locked>> | 86% | 56,014 psi | 88% | 2943 fps | 100% |
| Somchem S385 | <<locked>> | 90% | 57,087 psi | 89% | 2969 fps | 100% |
| Vihtavuori N150 | <<locked>> | 82% | 57,348 psi | 90% | 2858 fps | 100% |
| Vihtavuori N160 | <<locked>> | 84% | 56,811 psi | 89% | 2930 fps | 100% |
| Vihtavuori N165 | <<locked>> | 94% | 56,913 psi | 89% | 2953 fps | 100% |
| Vihtavuori N550 | <<locked>> | 84% | 55,985 psi | 88% | 2936 fps | 100% |
| Vihtavuori N555 | <<locked>> | 90% | 55,637 psi | 87% | 2966 fps | 100% |
| Vihtavuori N560 | <<locked>> | 90% | 55,390 psi | 87% | 3045 fps | 99.1% |
| Vihtavuori N565 | <<locked>> | 96% | 55,550 psi | 87% | 3028 fps | 99.3% |
| Vihtavuori N568ᴾ | <<locked>> | 100% | 56,289 psi | 88% | 3091 fps | 98.6% |
| Vihtavuori N570ᴾ | <<locked>> | 100% | 53,229 psi | 83% | 3084 fps | 96.4% |
| Winchester 6.5 StaBALL | <<locked>> | 84% | 56,202 psi | 88% | 2881 fps | 100% |
| Winchester 760 | <<locked>> | 82% | 54,882 psi | 86% | 2963 fps | 100% |
| Winchester StaBALL HD | <<locked>> | 94% | 55,666 psi | 87% | 3077 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 92% | 56,985 psi | 89% | 2966 fps | 99.9% |
Recommended = one of the top powders for this cartridge and bullet combination.
Start Load - Barrel Length: 25.6"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 3100 | <<locked>> | 80% | 37,289 psi | 58% | 2598 fps | 98.9% |
| Accurate 4350 | <<locked>> | 80% | 49,632 psi | 78% | 2848 fps | 100% |
| Accurate High Country | <<locked>> | 80% | 40,567 psi | 64% | 2772 fps | 96.6% |
| Accurate MAGPRO | <<locked>> | 82% | 41,017 psi | 64% | 2772 fps | 95.3% |
| ADI AR 2209 | <<locked>> | 80% | 41,278 psi | 65% | 2726 fps | 97.8% |
| ADI AR 2213 | <<locked>> | 80% | 36,869 psi | 58% | 2654 fps | 95% |
| ADI AR 2217 | <<locked>> | 90% | 38,130 psi | 60% | 2684 fps | 95.9% |
| ADI AR 2225 | <<locked>> | 86% | 30,356 psi | 48% | 2530 fps | 95.8% |
| Alliant Power Pro Varmint | <<locked>> | 80% | 41,684 psi | 65% | 2730 fps | 97.9% |
| Alliant Reloder-16 | <<locked>> | 80% | 47,456 psi | 74% | 2851 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 80% | 41,292 psi | 65% | 2723 fps | 97.8% |
| Alliant Reloder-22 | <<locked>> | 80% | 37,202 psi | 58% | 2667 fps | 96.7% |
| Alliant Reloder-23 | <<locked>> | 80% | 35,926 psi | 56% | 2625 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 80% | 31,111 psi | 49% | 2539 fps | 97.9% |
| Alliant Reloder-26 | <<locked>> | 80% | 39,726 psi | 62% | 2776 fps | 99.9% |
| Baschieri & Pellagri 109 | <<locked>> | 88% | 47,065 psi | 74% | 2812 fps | 95.1% |
| Bofors RP15 | <<locked>> | 80% | 34,548 psi | 54% | 2602 fps | 95.6% |
| Bofors RP30 | <<locked>> | 86% | 34,969 psi | 55% | 2641 fps | 95% |
| Bofors RP5 | <<locked>> | 80% | 37,202 psi | 58% | 2667 fps | 96.7% |
| Bofors RP7 | <<locked>> | 80% | 51,706 psi | 81% | 2848 fps | 99.8% |
| Hodgdon H1000 | <<locked>> | 86% | 36,506 psi | 57% | 2651 fps | 95.9% |
| Hodgdon H414 | <<locked>> | 80% | 51,053 psi | 80% | 2900 fps | 99.9% |
| Hodgdon H4350 | <<locked>> | 80% | 53,519 psi | 84% | 2913 fps | 99.7% |
| Hodgdon H4831 | <<locked>> | 80% | 39,349 psi | 62% | 2664 fps | 95.3% |
| Hodgdon H4831 SC | <<locked>> | 80% | 38,667 psi | 61% | 2648 fps | 95% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 44,759 psi | 70% | 2730 fps | 100% |
| Hodgdon Retumbo | 63.3 gr | 82% | 32,474 psi | 51% | 2625 fps | 95.4% |
| Hodgdon Superformance | <<locked>> | 80% | 51,155 psi | 80% | 2933 fps | 99.9% |
| Hodgdon TrailBoss | <<locked>> | 80% | 28,007 psi | 44% | 1663 fps | 100% |
| IMR 4350 | <<locked>> | 80% | 47,094 psi | 74% | 2782 fps | 99.5% |
| IMR 4451 Enduron | <<locked>> | 80% | 52,997 psi | 83% | 2871 fps | 100% |
| IMR 4831 | <<locked>> | 80% | 47,036 psi | 74% | 2789 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 80% | 40,930 psi | 64% | 2664 fps | 96% |
| IMR 7828 SSC | <<locked>> | 82% | 38,029 psi | 60% | 2697 fps | 95.6% |
| IMR 8133 Enduron | <<locked>> | 94% | 35,636 psi | 56% | 2680 fps | 95.1% |
| Lovex S065 | <<locked>> | 80% | 50,618 psi | 79% | 2818 fps | 100% |
| Lovex S070 | <<locked>> | 80% | 48,892 psi | 77% | 2812 fps | 99.9% |
| Lovex S071 | <<locked>> | 80% | 32,198 psi | 50% | 2477 fps | 97.5% |
| Norma 204 | <<locked>> | 80% | 47,311 psi | 74% | 2825 fps | 98.8% |
| Norma 217 | <<locked>> | 90% | 31,183 psi | 49% | 2579 fps | 95.6% |
| Norma MRP | <<locked>> | 80% | 39,102 psi | 61% | 2740 fps | 98.5% |
| Norma URP | <<locked>> | 80% | 48,312 psi | 76% | 2828 fps | 100% |
| Ramshot Grand | <<locked>> | 82% | 37,652 psi | 59% | 2700 fps | 95.9% |
| Ramshot Hunter | <<locked>> | 80% | 47,239 psi | 74% | 2831 fps | 99.9% |
| Ramshot Magnum | <<locked>> | 80% | 31,328 psi | 49% | 2516 fps | 95.3% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 28,674 psi | 45% | 1703 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 49,719 psi | 78% | 2871 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 47,776 psi | 75% | 2890 fps | 100% |
| ReloadSwiss RS 76 | 67.7 gr | 82% | 31,459 psi | 49% | 2595 fps | 96.2% |
| ReloadSwiss RS 80 | <<locked>> | 92% | 40,915 psi | 64% | 2815 fps | 95.6% |
| Rottweil R 904 | <<locked>> | 80% | 42,395 psi | 66% | 2703 fps | 97% |
| Rottweil R 905 | <<locked>> | 80% | 40,654 psi | 64% | 2707 fps | 97.8% |
| Rottweil R 907 | <<locked>> | 80% | 51,706 psi | 81% | 2848 fps | 99.8% |
| Shooters World Long Rifle | <<locked>> | 80% | 50,618 psi | 79% | 2818 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 48,892 psi | 77% | 2812 fps | 99.9% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 49,400 psi | 77% | 2766 fps | 99.9% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 40,321 psi | 63% | 2700 fps | 97.7% |
| Somchem S361 | <<locked>> | 80% | 43,236 psi | 68% | 2694 fps | 96.5% |
| Somchem S365 | <<locked>> | 80% | 45,759 psi | 72% | 2785 fps | 100% |
| Somchem S385 | <<locked>> | 80% | 41,278 psi | 65% | 2690 fps | 98.6% |
| Vihtavuori N150 | <<locked>> | 80% | 53,635 psi | 84% | 2808 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 49,835 psi | 78% | 2822 fps | 100% |
| Vihtavuori N165 | <<locked>> | 80% | 35,810 psi | 56% | 2562 fps | 96.8% |
| Vihtavuori N550 | <<locked>> | 80% | 49,081 psi | 77% | 2825 fps | 100% |
| Vihtavuori N555 | <<locked>> | 80% | 40,190 psi | 63% | 2700 fps | 100% |
| Vihtavuori N560 | 64.1 gr | 80% | 39,131 psi | 61% | 2726 fps | 95.4% |
| Vihtavuori N565 | <<locked>> | 86% | 39,552 psi | 62% | 2723 fps | 95.9% |
| Vihtavuori N568 | <<locked>> | 92% | 42,395 psi | 66% | 2835 fps | 95.4% |
| Vihtavuori N570 | <<locked>> | 98% | 49,559 psi | 78% | 3015 fps | 95.5% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 49,008 psi | 77% | 2779 fps | 100% |
| Winchester 760 | <<locked>> | 80% | 51,285 psi | 80% | 2900 fps | 99.9% |
| Winchester StaBALL HD | <<locked>> | 80% | 32,372 psi | 51% | 2657 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 80% | 37,724 psi | 59% | 2615 fps | 96.8% |
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 73 powders for 7 x 66 SE v. Hofe loaded with the .284 | 160gr | Winchester FailSafe. Hodgdon Retumbo delivers the highest muzzle velocity at 3,140 fps; across all powders the maximum-charge window runs from 1,860 fps to 3,140 fps. ADI AR 2217 gives the best case fill at 100 %, and 73 of the 73 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (440 MPa), the top charges use 59–90 %, leaving at least 10 % headroom. The 160.0 gr projectile in 0.284" calls for a 1:11.5 twist; slower twists will usually not stabilise this weight. ADI AR 2217, ADI AR 2225, Bofors RP30 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. Hodgdon Retumbo, ReloadSwiss RS 76, Vihtavuori N560 rank at the top here: for 7 x 66 SE v. Hofe with the .284 | 160gr | Winchester FailSafe 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.