Load Specifications
Load data in caliber 7.21 Firebird with .284 | 150gr | Lapua ScenarL bullet and 55 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are ADI AR 2218, Hodgdon Retumbo and ReloadSwiss RS 76.
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: 26"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 3100 | <<locked>> | 84% | 56,913 psi | 85% | 3071 fps | 100% |
| Accurate 8700ᴾ | <<locked>> | 100% | 53,243 psi | 80% | 3107 fps | 98.1% |
| Accurate High Country | <<locked>> | 82% | 59,103 psi | 89% | 3241 fps | 100% |
| Accurate MAGPRO | <<locked>> | 84% | 60,220 psi | 90% | 3251 fps | 99.9% |
| ADI AR 2209 | <<locked>> | 82% | 57,624 psi | 86% | 3163 fps | 100% |
| ADI AR 2213 | <<locked>> | 84% | 56,579 psi | 85% | 3182 fps | 100% |
| ADI AR 2217 | <<locked>> | 92% | 56,463 psi | 85% | 3169 fps | 100% |
| ADI AR 2218 | <<locked>> | 96% | 57,334 psi | 86% | 3304 fps | 99.4% |
| ADI AR 2225 | <<locked>> | 94% | 56,217 psi | 84% | 3189 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 82% | 57,696 psi | 86% | 3156 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 82% | 57,696 psi | 86% | 3156 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 82% | 57,116 psi | 86% | 3146 fps | 100% |
| Alliant Reloder-22 | <<locked>> | 84% | 57,145 psi | 86% | 3176 fps | 100% |
| Alliant Reloder-23 | <<locked>> | 86% | 59,234 psi | 89% | 3127 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 88% | 56,507 psi | 85% | 3156 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 94% | 59,596 psi | 89% | 3278 fps | 99.3% |
| Alliant Reloder-50 | <<locked>> | 98% | 60,002 psi | 90% | 3271 fps | 99.1% |
| Baschieri & Pellagri 109 | <<locked>> | 86% | 56,724 psi | 85% | 3140 fps | 99.1% |
| Bofors RP15 | <<locked>> | 86% | 56,739 psi | 85% | 3169 fps | 100% |
| Bofors RP30 | <<locked>> | 90% | 56,362 psi | 84% | 3179 fps | 100% |
| Bofors RP5 | <<locked>> | 84% | 57,145 psi | 86% | 3176 fps | 100% |
| Hodgdon H1000 | <<locked>> | 90% | 57,682 psi | 86% | 3182 fps | 100% |
| Hodgdon H4831 | <<locked>> | 84% | 59,045 psi | 89% | 3173 fps | 100% |
| Hodgdon H4831 SC | <<locked>> | 84% | 57,885 psi | 87% | 3153 fps | 99.9% |
| Hodgdon Retumbo | <<locked>> | 88% | 56,333 psi | 84% | 3258 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 38,043 psi | 57% | 2057 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 84% | 58,755 psi | 88% | 3140 fps | 100% |
| IMR 7828 SSC | <<locked>> | 86% | 59,219 psi | 89% | 3228 fps | 100% |
| IMR 7977 Enduron | <<locked>> | 90% | 57,566 psi | 86% | 3094 fps | 96.5% |
| IMR 8133 Enduron | <<locked>> | 98% | 59,045 psi | 89% | 3235 fps | 100% |
| Lovex D100 | <<locked>> | 94% | 59,321 psi | 89% | 3146 fps | 96% |
| Lovex S071 | <<locked>> | 90% | 59,001 psi | 88% | 3100 fps | 100% |
| Norma 217 | <<locked>> | 96% | 56,869 psi | 85% | 3196 fps | 100% |
| Norma MRP | <<locked>> | 82% | 57,479 psi | 86% | 3189 fps | 100% |
| Ramshot Grand | <<locked>> | 84% | 56,855 psi | 85% | 3189 fps | 100% |
| Ramshot Magnum | <<locked>> | 88% | 59,640 psi | 89% | 3176 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 39,131 psi | 59% | 2106 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 88% | 57,203 psi | 86% | 3235 fps | 100% |
| ReloadSwiss RS 80 | <<locked>> | 90% | 56,304 psi | 84% | 3205 fps | 99.8% |
| Rottweil R 904 | <<locked>> | 82% | 57,783 psi | 87% | 3130 fps | 100% |
| Rottweil R 905 | <<locked>> | 82% | 57,116 psi | 86% | 3143 fps | 100% |
| Shooters World 50 BMG | <<locked>> | 94% | 59,321 psi | 89% | 3146 fps | 96% |
| SNPE Vectan SP 13ᴾ | <<locked>> | 100% | 54,984 psi | 82% | 3120 fps | 98% |
| SNPE Vectan Tubal 8000 | <<locked>> | 82% | 56,753 psi | 85% | 3140 fps | 100% |
| Somchem S361 | <<locked>> | 82% | 59,190 psi | 89% | 3114 fps | 100% |
| Somchem S385 | <<locked>> | 82% | 57,435 psi | 86% | 3107 fps | 100% |
| Vihtavuori N165 | <<locked>> | 86% | 57,522 psi | 86% | 3094 fps | 100% |
| Vihtavuori N170 | <<locked>> | 90% | 57,116 psi | 86% | 3130 fps | 97.9% |
| Vihtavuori N555 | <<locked>> | 82% | 57,145 psi | 86% | 3104 fps | 100% |
| Vihtavuori N560 | <<locked>> | 82% | 56,710 psi | 85% | 3196 fps | 99.9% |
| Vihtavuori N565 | <<locked>> | 88% | 58,276 psi | 87% | 3192 fps | 100% |
| Vihtavuori N568 | <<locked>> | 90% | 56,550 psi | 85% | 3209 fps | 99.7% |
| Vihtavuori N570 | <<locked>> | 92% | 58,334 psi | 87% | 3284 fps | 98.9% |
| Winchester StaBALL HD | <<locked>> | 84% | 56,913 psi | 85% | 3169 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 84% | 57,159 psi | 86% | 3104 fps | 100% |
Recommended = one of the top powders for this cartridge and bullet combination.
Start Load - Barrel Length: 26"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 3100 | <<locked>> | 80% | 49,763 psi | 75% | 2959 fps | 100% |
| Accurate 8700 | <<locked>> | 94% | 42,554 psi | 64% | 2900 fps | 95.1% |
| Accurate High Country | <<locked>> | 80% | 55,158 psi | 83% | 3179 fps | 100% |
| Accurate MAGPRO | <<locked>> | 80% | 52,373 psi | 79% | 3120 fps | 99.4% |
| ADI AR 2209 | <<locked>> | 80% | 53,751 psi | 81% | 3100 fps | 100% |
| ADI AR 2213 | <<locked>> | 80% | 49,211 psi | 74% | 3051 fps | 99.5% |
| ADI AR 2217 | <<locked>> | 80% | 36,825 psi | 55% | 2779 fps | 97.4% |
| ADI AR 2218 | 96 gr | 88% | 42,453 psi | 64% | 2992 fps | 95.7% |
| ADI AR 2225 | <<locked>> | 80% | 34,142 psi | 51% | 2749 fps | 99.1% |
| Alliant Power Pro Varmint | <<locked>> | 80% | 54,085 psi | 81% | 3097 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 80% | 54,085 psi | 81% | 3097 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 80% | 53,577 psi | 80% | 3091 fps | 100% |
| Alliant Reloder-22 | <<locked>> | 80% | 50,009 psi | 75% | 3051 fps | 100% |
| Alliant Reloder-23 | <<locked>> | 80% | 48,631 psi | 73% | 2966 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 80% | 42,757 psi | 64% | 2920 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 84% | 40,857 psi | 61% | 2910 fps | 95% |
| Alliant Reloder-50 | <<locked>> | 90% | 44,382 psi | 67% | 2979 fps | 95.7% |
| Baschieri & Pellagri 109 | <<locked>> | 80% | 46,499 psi | 70% | 2946 fps | 97.2% |
| Bofors RP15 | <<locked>> | 80% | 46,514 psi | 70% | 2982 fps | 99.7% |
| Bofors RP30 | <<locked>> | 80% | 40,030 psi | 60% | 2864 fps | 98.3% |
| Bofors RP5 | <<locked>> | 80% | 50,009 psi | 75% | 3051 fps | 100% |
| Hodgdon H1000 | <<locked>> | 80% | 40,176 psi | 60% | 2861 fps | 98.8% |
| Hodgdon H4831 | <<locked>> | 80% | 51,459 psi | 77% | 3045 fps | 99.5% |
| Hodgdon H4831 SC | <<locked>> | 80% | 50,589 psi | 76% | 3028 fps | 99.4% |
| Hodgdon Retumbo | 82.3 gr | 80% | 41,930 psi | 63% | 2989 fps | 99.8% |
| Hodgdon TrailBoss | <<locked>> | 80% | 28,587 psi | 43% | 1844 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 80% | 51,677 psi | 77% | 3022 fps | 99.6% |
| IMR 7828 SSC | <<locked>> | 80% | 47,950 psi | 72% | 3035 fps | 99.4% |
| IMR 7977 Enduron | <<locked>> | 88% | 53,969 psi | 81% | 3031 fps | 95.7% |
| IMR 8133 Enduron | <<locked>> | 80% | 31,763 psi | 48% | 2661 fps | 95% |
| Lovex D100 | <<locked>> | 92% | 55,172 psi | 83% | 3077 fps | 95% |
| Lovex S071 | <<locked>> | 80% | 42,859 psi | 64% | 2828 fps | 100% |
| Norma 217 | <<locked>> | 80% | 32,213 psi | 48% | 2690 fps | 97.5% |
| Norma MRP | <<locked>> | 80% | 53,635 psi | 80% | 3127 fps | 100% |
| Ramshot Grand | <<locked>> | 80% | 48,849 psi | 73% | 3054 fps | 99.7% |
| Ramshot Magnum | <<locked>> | 80% | 44,135 psi | 66% | 2917 fps | 99.9% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 29,356 psi | 44% | 1886 fps | 100% |
| ReloadSwiss RS 76 | 88.1 gr | 80% | 41,785 psi | 63% | 2963 fps | 100% |
| ReloadSwiss RS 80 | <<locked>> | 80% | 38,464 psi | 58% | 2844 fps | 96.4% |
| Rottweil R 904 | <<locked>> | 80% | 54,027 psi | 81% | 3068 fps | 99.9% |
| Rottweil R 905 | <<locked>> | 80% | 53,476 psi | 80% | 3084 fps | 100% |
| Shooters World 50 BMG | <<locked>> | 92% | 55,172 psi | 83% | 3077 fps | 95% |
| SNPE Vectan SP 13 | <<locked>> | 94% | 44,628 psi | 67% | 2920 fps | 95.4% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 53,127 psi | 80% | 3081 fps | 100% |
| Somchem S361 | <<locked>> | 80% | 55,347 psi | 83% | 3058 fps | 99.8% |
| Somchem S385 | <<locked>> | 80% | 53,737 psi | 81% | 3048 fps | 100% |
| Vihtavuori N165 | <<locked>> | 80% | 47,224 psi | 71% | 2923 fps | 99.9% |
| Vihtavuori N170 | <<locked>> | 84% | 46,601 psi | 70% | 2933 fps | 95.4% |
| Vihtavuori N555 | <<locked>> | 80% | 53,563 psi | 80% | 3048 fps | 100% |
| Vihtavuori N560 | <<locked>> | 80% | 52,953 psi | 79% | 3130 fps | 99.7% |
| Vihtavuori N565 | <<locked>> | 80% | 44,353 psi | 66% | 2940 fps | 98.7% |
| Vihtavuori N568 | <<locked>> | 80% | 39,465 psi | 59% | 2867 fps | 96.2% |
| Vihtavuori N570 | <<locked>> | 84% | 43,540 psi | 65% | 2992 fps | 95.5% |
| Winchester StaBALL HD | <<locked>> | 80% | 49,023 psi | 73% | 3048 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 80% | 49,908 psi | 75% | 2986 fps | 99.9% |
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 55 powders for 7.21 Firebird loaded with the .284 | 150gr | Lapua ScenarL. ADI AR 2218 delivers the highest muzzle velocity at 3,304 fps; across all powders the maximum-charge window runs from 2,057 fps to 3,304 fps. Accurate 8700 gives the best case fill at 100 %, and 55 of the 55 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (460 MPa), the top charges use 57–90 %, leaving at least 10 % headroom. The 150.0 gr projectile in 0.284" calls for a 1:10.0 twist; slower twists will usually not stabilise this weight. Accurate 8700, Hodgdon TrailBoss, ReloadSwiss RS 14 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. ADI AR 2218, Hodgdon Retumbo, ReloadSwiss RS 76 rank at the top here: for 7.21 Firebird with the .284 | 150gr | Lapua ScenarL 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.