Load Specifications
Load data in caliber 7 x 66 SE v. Hofe with .284 | 145gr | Speer Boat-Tail bullet and 74 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Accurate MAGPRO, Ramshot Grand and Accurate High Country.
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: 25.6"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 3100 | <<locked>> | 94% | 56,681 psi | 89% | 3081 fps | 100% |
| Accurate 4350 | <<locked>> | 84% | 54,273 psi | 85% | 3058 fps | 100% |
| Accurate High Country | <<locked>> | 90% | 54,549 psi | 85% | 3179 fps | 98.8% |
| Accurate MAGPRO | <<locked>> | 92% | 55,347 psi | 87% | 3179 fps | 98% |
| ADI AR 2209 | <<locked>> | 90% | 54,998 psi | 86% | 3117 fps | 99.4% |
| ADI AR 2213 | <<locked>> | 94% | 56,434 psi | 88% | 3182 fps | 99% |
| ADI AR 2217ᴾ | <<locked>> | 100% | 50,792 psi | 80% | 3074 fps | 98.4% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 45,411 psi | 71% | 3031 fps | 99.6% |
| Alliant Reloder-16 | <<locked>> | 86% | 55,187 psi | 86% | 3120 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 82% | 56,043 psi | 88% | 3130 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 90% | 54,592 psi | 86% | 3104 fps | 99.4% |
| Alliant Reloder-22 | <<locked>> | 94% | 56,550 psi | 89% | 3176 fps | 99.6% |
| Alliant Reloder-23 | <<locked>> | 94% | 54,186 psi | 85% | 3091 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 57,305 psi | 90% | 3209 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 90% | 54,534 psi | 85% | 3182 fps | 100% |
| Baschieri & Pellagri 109 | <<locked>> | 94% | 54,694 psi | 86% | 3077 fps | 96.1% |
| Bofors RP15 | <<locked>> | 96% | 55,695 psi | 87% | 3159 fps | 99.5% |
| Bofors RP30ᴾ | <<locked>> | 100% | 53,432 psi | 84% | 3153 fps | 99% |
| Bofors RP5 | <<locked>> | 94% | 56,550 psi | 89% | 3176 fps | 99.6% |
| Bofors RP7 | <<locked>> | 84% | 56,246 psi | 88% | 3058 fps | 99.8% |
| Hodgdon H1000ᴾ | <<locked>> | 100% | 55,985 psi | 88% | 3166 fps | 99.5% |
| Hodgdon H414 | <<locked>> | 84% | 55,796 psi | 87% | 3117 fps | 100% |
| Hodgdon H4350 | <<locked>> | 82% | 54,708 psi | 86% | 3068 fps | 99.5% |
| Hodgdon H4831 | <<locked>> | 92% | 56,362 psi | 88% | 3114 fps | 98.4% |
| Hodgdon H4831 SC | <<locked>> | 92% | 55,376 psi | 87% | 3100 fps | 98.3% |
| Hodgdon Hybrid 100V | <<locked>> | 88% | 55,288 psi | 87% | 3035 fps | 100% |
| Hodgdon Retumboᴾ | <<locked>> | 100% | 56,246 psi | 88% | 3291 fps | 100% |
| Hodgdon Superformance | <<locked>> | 84% | 56,463 psi | 88% | 3153 fps | 99.9% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 37,188 psi | 58% | 1959 fps | 100% |
| IMR 4350 | <<locked>> | 86% | 54,607 psi | 86% | 3045 fps | 99.8% |
| IMR 4451 Enduron | <<locked>> | 82% | 54,230 psi | 85% | 3025 fps | 99.9% |
| IMR 4831 | <<locked>> | 86% | 54,592 psi | 86% | 3051 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 92% | 57,363 psi | 90% | 3100 fps | 98.7% |
| IMR 7828 SSC | <<locked>> | 94% | 54,534 psi | 85% | 3159 fps | 98.8% |
| IMR 8133 Enduronᴾ | <<locked>> | 100% | 41,031 psi | 64% | 2927 fps | 96% |
| Lovex S065 | <<locked>> | 84% | 54,969 psi | 86% | 3025 fps | 100% |
| Lovex S070 | <<locked>> | 86% | 56,710 psi | 89% | 3077 fps | 100% |
| Lovex S071 | <<locked>> | 98% | 54,331 psi | 85% | 3041 fps | 100% |
| Norma 204 | <<locked>> | 86% | 55,405 psi | 87% | 3100 fps | 99.3% |
| Norma 217ᴾ | <<locked>> | 100% | 41,147 psi | 64% | 2953 fps | 98.3% |
| Norma MRP | <<locked>> | 92% | 56,550 psi | 89% | 3202 fps | 100% |
| Norma URP | <<locked>> | 86% | 56,217 psi | 88% | 3094 fps | 100% |
| Ramshot Grand | <<locked>> | 94% | 55,129 psi | 86% | 3179 fps | 99.1% |
| Ramshot Hunter | <<locked>> | 86% | 54,984 psi | 86% | 3100 fps | 100% |
| Ramshot Magnum | <<locked>> | 96% | 53,548 psi | 84% | 3107 fps | 99.8% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 38,000 psi | 60% | 2005 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 84% | 54,172 psi | 85% | 3081 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 86% | 56,492 psi | 89% | 3173 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 57,377 psi | 90% | 3287 fps | 100% |
| ReloadSwiss RS 80ᴾ | <<locked>> | 100% | 52,272 psi | 82% | 3166 fps | 97.7% |
| Rottweil R 904 | <<locked>> | 90% | 56,144 psi | 88% | 3087 fps | 98.9% |
| Rottweil R 905 | <<locked>> | 92% | 57,711 psi | 90% | 3153 fps | 99.7% |
| Rottweil R 907 | <<locked>> | 84% | 56,246 psi | 88% | 3058 fps | 99.8% |
| Shooters World Long Rifle | <<locked>> | 84% | 54,969 psi | 86% | 3025 fps | 100% |
| Shooters World SW4350 | <<locked>> | 86% | 56,710 psi | 89% | 3077 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 82% | 57,421 psi | 90% | 2917 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 84% | 54,143 psi | 85% | 2976 fps | 99.9% |
| SNPE Vectan Tubal 8000 | <<locked>> | 92% | 57,276 psi | 90% | 3146 fps | 99.7% |
| Somchem S355 | <<locked>> | 82% | 57,406 psi | 90% | 3051 fps | 100% |
| Somchem S361 | <<locked>> | 90% | 57,725 psi | 90% | 3074 fps | 98.6% |
| Somchem S365 | <<locked>> | 88% | 56,768 psi | 89% | 3097 fps | 100% |
| Somchem S385 | <<locked>> | 90% | 54,723 psi | 86% | 3068 fps | 99.8% |
| Vihtavuori N150 | <<locked>> | 82% | 55,071 psi | 86% | 2966 fps | 100% |
| Vihtavuori N160 | <<locked>> | 84% | 54,433 psi | 85% | 3031 fps | 100% |
| Vihtavuori N165 | <<locked>> | 94% | 54,114 psi | 85% | 3041 fps | 99.6% |
| Vihtavuori N550 | <<locked>> | 86% | 57,145 psi | 90% | 3094 fps | 100% |
| Vihtavuori N555 | <<locked>> | 92% | 56,347 psi | 88% | 3120 fps | 100% |
| Vihtavuori N560 | <<locked>> | 92% | 56,304 psi | 88% | 3196 fps | 98.6% |
| Vihtavuori N565 | <<locked>> | 98% | 56,362 psi | 88% | 3173 fps | 98.8% |
| Vihtavuori N568ᴾ | <<locked>> | 100% | 53,055 psi | 83% | 3166 fps | 97.3% |
| Winchester 6.5 StaBALL | <<locked>> | 86% | 57,624 psi | 90% | 3038 fps | 100% |
| Winchester 760 | <<locked>> | 84% | 56,028 psi | 88% | 3120 fps | 100% |
| Winchester StaBALL HD | <<locked>> | 96% | 56,217 psi | 88% | 3235 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 92% | 54,418 psi | 85% | 3058 fps | 99.3% |
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% | 35,346 psi | 55% | 2671 fps | 97.6% |
| Accurate 4350 | <<locked>> | 80% | 47,224 psi | 74% | 2940 fps | 100% |
| Accurate High Country | 67.5 gr | 82% | 41,162 psi | 65% | 2910 fps | 95.7% |
| Accurate MAGPRO | 72.1 gr | 86% | 44,788 psi | 70% | 2976 fps | 95.5% |
| ADI AR 2209 | <<locked>> | 80% | 39,378 psi | 62% | 2805 fps | 96.3% |
| ADI AR 2213 | <<locked>> | 84% | 40,234 psi | 63% | 2854 fps | 95.1% |
| ADI AR 2217 | <<locked>> | 94% | 41,437 psi | 65% | 2877 fps | 95.9% |
| ADI AR 2225 | <<locked>> | 90% | 32,764 psi | 51% | 2707 fps | 95.7% |
| Alliant Reloder-16 | <<locked>> | 80% | 45,223 psi | 71% | 2949 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 80% | 52,373 psi | 82% | 3071 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 80% | 39,349 psi | 62% | 2799 fps | 96.3% |
| Alliant Reloder-22 | <<locked>> | 82% | 37,768 psi | 59% | 2799 fps | 95.9% |
| Alliant Reloder-23 | <<locked>> | 80% | 33,852 psi | 53% | 2700 fps | 99.7% |
| Alliant Reloder-25 | <<locked>> | 80% | 29,544 psi | 46% | 2602 fps | 96% |
| Alliant Reloder-26 | <<locked>> | 80% | 37,231 psi | 58% | 2844 fps | 99.3% |
| Baschieri & Pellagri 109 | <<locked>> | 92% | 51,314 psi | 80% | 3015 fps | 95.3% |
| Bofors RP15 | <<locked>> | 84% | 37,434 psi | 59% | 2792 fps | 95.6% |
| Bofors RP30 | <<locked>> | 90% | 37,855 psi | 59% | 2831 fps | 95.1% |
| Bofors RP5 | <<locked>> | 82% | 37,768 psi | 59% | 2799 fps | 95.9% |
| Bofors RP7 | <<locked>> | 80% | 49,603 psi | 78% | 2940 fps | 99.3% |
| Hodgdon H1000 | <<locked>> | 90% | 39,755 psi | 62% | 2841 fps | 96% |
| Hodgdon H414 | <<locked>> | 80% | 48,704 psi | 76% | 2992 fps | 99.5% |
| Hodgdon H4350 | <<locked>> | 80% | 51,300 psi | 80% | 3009 fps | 99.1% |
| Hodgdon H4831 | <<locked>> | 84% | 42,931 psi | 67% | 2864 fps | 95.4% |
| Hodgdon H4831 SC | <<locked>> | 84% | 42,206 psi | 66% | 2844 fps | 95.1% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 42,540 psi | 67% | 2822 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 86% | 35,114 psi | 55% | 2812 fps | 95.4% |
| Hodgdon Superformance | <<locked>> | 80% | 48,675 psi | 76% | 3018 fps | 99.4% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,891 psi | 44% | 1752 fps | 100% |
| IMR 4350 | <<locked>> | 80% | 45,150 psi | 71% | 2871 fps | 98.7% |
| IMR 4451 Enduron | <<locked>> | 80% | 50,879 psi | 80% | 2966 fps | 99.6% |
| IMR 4831 | <<locked>> | 80% | 44,875 psi | 70% | 2884 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 82% | 41,713 psi | 65% | 2802 fps | 95.2% |
| IMR 7828 SSC | <<locked>> | 86% | 41,365 psi | 65% | 2897 fps | 95.7% |
| IMR 8133 Enduron | <<locked>> | 98% | 38,276 psi | 60% | 2861 fps | 95% |
| Lovex S065 | <<locked>> | 80% | 48,515 psi | 76% | 2917 fps | 99.9% |
| Lovex S070 | <<locked>> | 80% | 46,920 psi | 74% | 2904 fps | 99.4% |
| Lovex S071 | <<locked>> | 80% | 30,472 psi | 48% | 2539 fps | 95.8% |
| Norma 204 | <<locked>> | 80% | 45,324 psi | 71% | 2913 fps | 97.7% |
| Norma 217 | <<locked>> | 94% | 33,547 psi | 53% | 2756 fps | 95.5% |
| Norma MRP | <<locked>> | 80% | 36,811 psi | 58% | 2805 fps | 97% |
| Norma URP | <<locked>> | 80% | 46,180 psi | 72% | 2927 fps | 100% |
| Ramshot Grand | 68.6 gr | 84% | 38,421 psi | 60% | 2835 fps | 95% |
| Ramshot Hunter | <<locked>> | 80% | 45,136 psi | 71% | 2923 fps | 99.5% |
| Ramshot Magnum | <<locked>> | 84% | 34,229 psi | 54% | 2707 fps | 95.4% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 28,500 psi | 45% | 1795 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 47,152 psi | 74% | 2959 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 45,339 psi | 71% | 2979 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 84% | 32,010 psi | 50% | 2717 fps | 95.1% |
| ReloadSwiss RS 80 | <<locked>> | 96% | 44,643 psi | 70% | 3015 fps | 95.7% |
| Rottweil R 904 | <<locked>> | 80% | 40,625 psi | 64% | 2782 fps | 95.4% |
| Rottweil R 905 | <<locked>> | 80% | 38,682 psi | 61% | 2785 fps | 96.3% |
| Rottweil R 907 | <<locked>> | 80% | 49,603 psi | 78% | 2940 fps | 99.3% |
| Shooters World Long Rifle | <<locked>> | 80% | 48,515 psi | 76% | 2917 fps | 99.9% |
| Shooters World SW4350 | <<locked>> | 80% | 46,920 psi | 74% | 2904 fps | 99.4% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 53,954 psi | 85% | 2871 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 47,500 psi | 74% | 2861 fps | 99.4% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 38,348 psi | 60% | 2779 fps | 96.1% |
| Somchem S355 | <<locked>> | 80% | 53,795 psi | 84% | 2995 fps | 100% |
| Somchem S361 | <<locked>> | 82% | 44,280 psi | 69% | 2831 fps | 95.8% |
| Somchem S365 | <<locked>> | 80% | 43,381 psi | 68% | 2881 fps | 100% |
| Somchem S385 | <<locked>> | 80% | 39,320 psi | 62% | 2766 fps | 97.3% |
| Vihtavuori N150 | <<locked>> | 80% | 51,576 psi | 81% | 2917 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 47,616 psi | 75% | 2920 fps | 100% |
| Vihtavuori N165 | <<locked>> | 80% | 34,055 psi | 53% | 2631 fps | 95.1% |
| Vihtavuori N550 | <<locked>> | 80% | 47,065 psi | 74% | 2923 fps | 100% |
| Vihtavuori N555 | <<locked>> | 80% | 38,087 psi | 60% | 2782 fps | 99.7% |
| Vihtavuori N560 | <<locked>> | 84% | 42,569 psi | 67% | 2930 fps | 95.5% |
| Vihtavuori N565 | <<locked>> | 90% | 42,859 psi | 67% | 2917 fps | 95.9% |
| Vihtavuori N568 | <<locked>> | 96% | 46,006 psi | 72% | 3031 fps | 95.5% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 46,804 psi | 73% | 2874 fps | 100% |
| Winchester 760 | <<locked>> | 80% | 48,936 psi | 77% | 2992 fps | 99.5% |
| Winchester StaBALL HD | <<locked>> | 80% | 30,240 psi | 47% | 2720 fps | 99.9% |
| Winchester Supreme 780 | <<locked>> | 80% | 35,810 psi | 56% | 2684 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 78 powders for 7 x 66 SE v. Hofe loaded with the .284 | 145gr | Speer Boat-Tail. Hodgdon Retumbo delivers the highest muzzle velocity at 3,291 fps; across all powders the maximum-charge window runs from 1,959 fps to 3,291 fps. ADI AR 2217 gives the best case fill at 100 %, and 78 of the 78 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 145.0 gr projectile in 0.284" calls for a 1:12.0 twist; slower twists will usually not stabilise this weight. ADI AR 2217, ADI AR 2225, Alliant Reloder-25 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. Accurate MAGPRO, Ramshot Grand, Accurate High Country rank at the top here: for 7 x 66 SE v. Hofe with the .284 | 145gr | Speer Boat-Tail they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, Alliant Reloder-33, IMR 7977 Enduron, Vihtavuori N170 burn incompletely and react more sensitively to barrel length and temperature. Always begin at the start load and work up in small increments while checking case and primer for pressure signs.