Load Specifications
Load data in caliber 7 x 66 SE v. Hofe with .284 | 158gr | Prvi Partizan Grom 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 Winchester StaBALL HD.
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% | 55,172 psi | 86% | 2936 fps | 100% |
| Accurate 4350 | <<locked>> | 84% | 56,028 psi | 88% | 2963 fps | 100% |
| Accurate High Country | <<locked>> | 90% | 56,565 psi | 89% | 3094 fps | 99.5% |
| Accurate MAGPRO | <<locked>> | 92% | 57,537 psi | 90% | 3100 fps | 98.9% |
| ADI AR 2209 | <<locked>> | 90% | 56,985 psi | 89% | 3028 fps | 99.8% |
| ADI AR 2213 | <<locked>> | 92% | 54,665 psi | 86% | 3035 fps | 99.2% |
| ADI AR 2217ᴾ | <<locked>> | 100% | 52,823 psi | 83% | 2999 fps | 99.3% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 47,253 psi | 74% | 2959 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 90% | 57,000 psi | 89% | 3022 fps | 99.8% |
| Alliant Reloder-16 | <<locked>> | 86% | 57,217 psi | 90% | 3022 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 90% | 56,333 psi | 88% | 3015 fps | 99.8% |
| Alliant Reloder-22 | <<locked>> | 92% | 54,897 psi | 86% | 3031 fps | 99.8% |
| Alliant Reloder-23 | <<locked>> | 94% | 56,289 psi | 88% | 2995 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 98% | 55,985 psi | 88% | 3068 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 90% | 56,956 psi | 89% | 3091 fps | 100% |
| Baschieri & Pellagri 109 | <<locked>> | 94% | 56,130 psi | 88% | 2995 fps | 97.2% |
| Bofors RP15 | <<locked>> | 96% | 57,682 psi | 90% | 3071 fps | 99.9% |
| Bofors RP30ᴾ | <<locked>> | 100% | 55,579 psi | 87% | 3071 fps | 99.6% |
| Bofors RP5 | <<locked>> | 92% | 54,897 psi | 86% | 3031 fps | 99.8% |
| Bofors RP7 | <<locked>> | 82% | 54,563 psi | 86% | 2910 fps | 99.9% |
| Hodgdon H1000 | <<locked>> | 98% | 54,288 psi | 85% | 3022 fps | 99.7% |
| Hodgdon H414 | <<locked>> | 84% | 57,595 psi | 90% | 3022 fps | 100% |
| Hodgdon H4350 | <<locked>> | 82% | 56,420 psi | 88% | 2976 fps | 99.9% |
| Hodgdon H4831 | <<locked>> | 90% | 54,447 psi | 85% | 2969 fps | 98.7% |
| Hodgdon H4831 SC | <<locked>> | 92% | 57,087 psi | 89% | 3012 fps | 99% |
| Hodgdon Hybrid 100V | <<locked>> | 88% | 57,276 psi | 90% | 2936 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 98% | 54,810 psi | 86% | 3146 fps | 100% |
| Hodgdon Superformance | <<locked>> | 82% | 54,215 psi | 85% | 2999 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 37,275 psi | 58% | 1870 fps | 100% |
| IMR 4350 | <<locked>> | 86% | 56,188 psi | 88% | 2953 fps | 100% |
| IMR 4451 Enduron | <<locked>> | 82% | 55,883 psi | 88% | 2933 fps | 100% |
| IMR 4831 | <<locked>> | 86% | 56,289 psi | 88% | 2953 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 90% | 55,535 psi | 87% | 2953 fps | 98.9% |
| IMR 7828 SSC | <<locked>> | 94% | 56,536 psi | 89% | 3074 fps | 99.4% |
| IMR 8133 Enduronᴾ | <<locked>> | 100% | 42,728 psi | 67% | 2858 fps | 97.4% |
| Lovex S065 | <<locked>> | 84% | 56,521 psi | 89% | 2927 fps | 100% |
| Lovex S070 | <<locked>> | 84% | 54,839 psi | 86% | 2927 fps | 100% |
| Lovex S071 | <<locked>> | 98% | 56,362 psi | 88% | 2956 fps | 100% |
| Norma 204 | <<locked>> | 86% | 57,261 psi | 90% | 3009 fps | 99.8% |
| Norma 217ᴾ | <<locked>> | 100% | 43,018 psi | 67% | 2887 fps | 99.3% |
| Norma MRP | <<locked>> | 90% | 54,781 psi | 86% | 3051 fps | 100% |
| Norma URP | <<locked>> | 84% | 54,375 psi | 85% | 2943 fps | 100% |
| Ramshot Grand | <<locked>> | 94% | 57,537 psi | 90% | 3097 fps | 99.7% |
| Ramshot Hunter | <<locked>> | 86% | 56,927 psi | 89% | 3009 fps | 100% |
| Ramshot Magnum | <<locked>> | 96% | 55,898 psi | 88% | 3028 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 38,145 psi | 60% | 1913 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 84% | 56,159 psi | 88% | 2986 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 84% | 54,447 psi | 85% | 3015 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 98% | 55,550 psi | 87% | 3140 fps | 100% |
| ReloadSwiss RS 80ᴾ | <<locked>> | 100% | 54,650 psi | 86% | 3094 fps | 98.7% |
| Rottweil R 904 | <<locked>> | 88% | 54,433 psi | 85% | 2940 fps | 99.1% |
| Rottweil R 905 | <<locked>> | 90% | 55,985 psi | 88% | 3005 fps | 99.8% |
| Rottweil R 907 | <<locked>> | 82% | 54,563 psi | 86% | 2910 fps | 99.9% |
| Shooters World Long Rifle | <<locked>> | 84% | 56,521 psi | 89% | 2927 fps | 100% |
| Shooters World SW4350 | <<locked>> | 84% | 54,839 psi | 86% | 2927 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 84% | 55,767 psi | 87% | 2884 fps | 100% |
| SNPE Vectan Tubal 8000 | <<locked>> | 90% | 55,564 psi | 87% | 2999 fps | 99.8% |
| Somchem S361 | <<locked>> | 88% | 55,738 psi | 87% | 2933 fps | 98.8% |
| Somchem S365 | <<locked>> | 86% | 55,172 psi | 86% | 2946 fps | 100% |
| Somchem S385 | <<locked>> | 90% | 56,521 psi | 89% | 2976 fps | 100% |
| Vihtavuori N150 | <<locked>> | 82% | 56,623 psi | 89% | 2867 fps | 100% |
| Vihtavuori N160 | <<locked>> | 84% | 56,028 psi | 88% | 2933 fps | 100% |
| Vihtavuori N165 | <<locked>> | 94% | 56,101 psi | 88% | 2956 fps | 99.9% |
| Vihtavuori N550 | <<locked>> | 84% | 55,259 psi | 87% | 2940 fps | 100% |
| Vihtavuori N555 | <<locked>> | 90% | 54,984 psi | 86% | 2972 fps | 100% |
| Vihtavuori N560 | <<locked>> | 90% | 54,520 psi | 85% | 3048 fps | 98.9% |
| Vihtavuori N565 | <<locked>> | 96% | 54,665 psi | 86% | 3031 fps | 99.1% |
| Vihtavuori N568ᴾ | <<locked>> | 100% | 55,593 psi | 87% | 3094 fps | 98.4% |
| Vihtavuori N570ᴾ | <<locked>> | 100% | 52,344 psi | 82% | 3081 fps | 96% |
| Winchester 6.5 StaBALL | <<locked>> | 84% | 55,477 psi | 87% | 2887 fps | 100% |
| Winchester 760 | <<locked>> | 82% | 54,070 psi | 85% | 2966 fps | 100% |
| Winchester StaBALL HD | <<locked>> | 94% | 54,868 psi | 86% | 3087 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 92% | 56,420 psi | 88% | 2972 fps | 99.8% |
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% | 36,854 psi | 58% | 2602 fps | 98.7% |
| Accurate 4350 | <<locked>> | 80% | 49,081 psi | 77% | 2854 fps | 100% |
| Accurate High Country | <<locked>> | 80% | 39,871 psi | 62% | 2769 fps | 96.2% |
| Accurate MAGPRO | <<locked>> | 82% | 40,509 psi | 63% | 2776 fps | 95% |
| ADI AR 2209 | <<locked>> | 80% | 40,843 psi | 64% | 2733 fps | 97.5% |
| ADI AR 2213 | <<locked>> | 82% | 38,972 psi | 61% | 2720 fps | 95.6% |
| ADI AR 2217 | <<locked>> | 90% | 37,739 psi | 59% | 2690 fps | 95.5% |
| ADI AR 2225 | <<locked>> | 86% | 29,878 psi | 47% | 2526 fps | 95.2% |
| Alliant Power Pro Varmint | <<locked>> | 80% | 41,220 psi | 65% | 2733 fps | 97.6% |
| Alliant Reloder-16 | <<locked>> | 80% | 46,920 psi | 74% | 2858 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 80% | 40,843 psi | 64% | 2726 fps | 97.5% |
| Alliant Reloder-22 | <<locked>> | 80% | 36,622 psi | 57% | 2667 fps | 96.4% |
| Alliant Reloder-23 | <<locked>> | 80% | 35,462 psi | 56% | 2631 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 80% | 30,748 psi | 48% | 2543 fps | 97.6% |
| Alliant Reloder-26 | <<locked>> | 80% | 39,131 psi | 61% | 2779 fps | 99.9% |
| Baschieri & Pellagri 109 | <<locked>> | 90% | 49,647 psi | 78% | 2877 fps | 95.7% |
| Bofors RP15 | <<locked>> | 80% | 34,127 psi | 53% | 2602 fps | 95.2% |
| Bofors RP30 | <<locked>> | 88% | 36,912 psi | 58% | 2707 fps | 95.7% |
| Bofors RP5 | <<locked>> | 80% | 36,622 psi | 57% | 2667 fps | 96.4% |
| Bofors RP7 | <<locked>> | 80% | 51,242 psi | 80% | 2854 fps | 99.8% |
| Hodgdon H1000 | <<locked>> | 86% | 35,955 psi | 56% | 2648 fps | 95.5% |
| Hodgdon H414 | <<locked>> | 80% | 50,560 psi | 79% | 2907 fps | 99.9% |
| Hodgdon H4350 | <<locked>> | 80% | 52,779 psi | 83% | 2917 fps | 99.6% |
| Hodgdon H4831 | <<locked>> | 82% | 41,582 psi | 65% | 2726 fps | 95.8% |
| Hodgdon H4831 SC | <<locked>> | 82% | 40,828 psi | 64% | 2710 fps | 95.6% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 44,251 psi | 69% | 2736 fps | 100% |
| Hodgdon Retumbo | 64.7 gr | 84% | 34,229 psi | 54% | 2687 fps | 96.1% |
| Hodgdon Superformance | <<locked>> | 80% | 50,343 psi | 79% | 2933 fps | 99.8% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,876 psi | 44% | 1670 fps | 100% |
| IMR 4350 | <<locked>> | 80% | 46,630 psi | 73% | 2789 fps | 99.3% |
| IMR 4451 Enduron | <<locked>> | 80% | 52,576 psi | 82% | 2877 fps | 99.9% |
| IMR 4831 | <<locked>> | 80% | 46,528 psi | 73% | 2795 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 80% | 40,553 psi | 64% | 2667 fps | 95.7% |
| IMR 7828 SSC | <<locked>> | 82% | 37,565 psi | 59% | 2697 fps | 95.2% |
| IMR 8133 Enduron | <<locked>> | 96% | 37,376 psi | 59% | 2736 fps | 95.7% |
| Lovex S065 | <<locked>> | 80% | 50,169 psi | 79% | 2828 fps | 100% |
| Lovex S070 | <<locked>> | 80% | 48,414 psi | 76% | 2818 fps | 99.8% |
| Lovex S071 | <<locked>> | 80% | 31,807 psi | 50% | 2477 fps | 97.2% |
| Norma 204 | <<locked>> | 80% | 46,833 psi | 73% | 2831 fps | 98.7% |
| Norma 217 | <<locked>> | 90% | 30,763 psi | 48% | 2582 fps | 95.2% |
| Norma MRP | <<locked>> | 80% | 38,450 psi | 60% | 2740 fps | 98.3% |
| Norma URP | <<locked>> | 80% | 47,819 psi | 75% | 2835 fps | 100% |
| Ramshot Grand | <<locked>> | 82% | 37,188 psi | 58% | 2703 fps | 95.5% |
| Ramshot Hunter | <<locked>> | 80% | 46,760 psi | 73% | 2841 fps | 99.9% |
| Ramshot Magnum | <<locked>> | 82% | 33,228 psi | 52% | 2582 fps | 96% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 28,543 psi | 45% | 1709 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 48,965 psi | 77% | 2874 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 47,210 psi | 74% | 2897 fps | 100% |
| ReloadSwiss RS 76 | 67.6 gr | 82% | 31,096 psi | 49% | 2595 fps | 95.8% |
| ReloadSwiss RS 80 | <<locked>> | 92% | 40,364 psi | 63% | 2818 fps | 95.2% |
| Rottweil R 904 | <<locked>> | 80% | 42,003 psi | 66% | 2710 fps | 96.7% |
| Rottweil R 905 | <<locked>> | 80% | 40,190 psi | 63% | 2713 fps | 97.5% |
| Rottweil R 907 | <<locked>> | 80% | 51,242 psi | 80% | 2854 fps | 99.8% |
| Shooters World Long Rifle | <<locked>> | 80% | 50,169 psi | 79% | 2828 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 48,414 psi | 76% | 2818 fps | 99.8% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 48,950 psi | 77% | 2772 fps | 99.8% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 39,856 psi | 62% | 2707 fps | 97.4% |
| Somchem S361 | <<locked>> | 80% | 42,815 psi | 67% | 2697 fps | 96.2% |
| Somchem S365 | <<locked>> | 80% | 45,208 psi | 71% | 2792 fps | 100% |
| Somchem S385 | <<locked>> | 80% | 40,669 psi | 64% | 2694 fps | 98.3% |
| Vihtavuori N150 | <<locked>> | 80% | 53,156 psi | 83% | 2818 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 49,313 psi | 77% | 2831 fps | 100% |
| Vihtavuori N165 | <<locked>> | 80% | 35,389 psi | 55% | 2566 fps | 96.5% |
| Vihtavuori N550 | <<locked>> | 80% | 48,602 psi | 76% | 2835 fps | 100% |
| Vihtavuori N555 | <<locked>> | 80% | 39,697 psi | 62% | 2707 fps | 100% |
| Vihtavuori N560 | <<locked>> | 80% | 38,479 psi | 60% | 2726 fps | 95% |
| Vihtavuori N565 | <<locked>> | 86% | 39,030 psi | 61% | 2726 fps | 95.5% |
| Vihtavuori N568 | <<locked>> | 94% | 44,701 psi | 70% | 2897 fps | 96% |
| Vihtavuori N570 | <<locked>> | 98% | 48,733 psi | 76% | 3012 fps | 95% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 48,341 psi | 76% | 2782 fps | 100% |
| Winchester 760 | <<locked>> | 80% | 50,560 psi | 79% | 2907 fps | 99.9% |
| Winchester StaBALL HD | 63.3 gr | 80% | 31,792 psi | 50% | 2661 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 80% | 37,289 psi | 58% | 2618 fps | 96.5% |
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 73 powders for 7 x 66 SE v. Hofe loaded with the .284 | 158gr | Prvi Partizan Grom. Hodgdon Retumbo delivers the highest muzzle velocity at 3,146 fps; across all powders the maximum-charge window runs from 1,870 fps to 3,146 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 58–90 %, leaving at least 10 % headroom. The 158.0 gr projectile in 0.284" calls for a 1:11.0 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, Winchester StaBALL HD rank at the top here: for 7 x 66 SE v. Hofe with the .284 | 158gr | Prvi Partizan Grom 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.