Load Specifications
Load data in caliber 7.21 Firebird with .284 | 130gr | Speer Soft Point bullet and 51 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Hodgdon Retumbo, ADI AR 2218 and ReloadSwiss RS 80.
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: 26"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 3100 | <<locked>> | 86% | 58,030 psi | 87% | 3264 fps | 100% |
| Accurate 8700ᴾ | <<locked>> | 100% | 50,198 psi | 75% | 3202 fps | 96.2% |
| Accurate MAGPRO | <<locked>> | 84% | 57,217 psi | 86% | 3376 fps | 99.3% |
| ADI AR 2209 | <<locked>> | 84% | 58,682 psi | 88% | 3360 fps | 100% |
| ADI AR 2213 | <<locked>> | 86% | 57,769 psi | 87% | 3376 fps | 99.8% |
| ADI AR 2217 | <<locked>> | 94% | 57,174 psi | 86% | 3350 fps | 99.9% |
| ADI AR 2218 | <<locked>> | 98% | 58,349 psi | 87% | 3481 fps | 98.8% |
| ADI AR 2225 | <<locked>> | 96% | 56,884 psi | 85% | 3373 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 84% | 58,276 psi | 87% | 3346 fps | 100% |
| Alliant Reloder-22 | <<locked>> | 86% | 58,291 psi | 87% | 3369 fps | 100% |
| Alliant Reloder-23 | <<locked>> | 88% | 60,307 psi | 90% | 3323 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 90% | 57,203 psi | 86% | 3346 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 82% | 57,406 psi | 86% | 3360 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 94% | 56,115 psi | 84% | 3376 fps | 98% |
| Alliant Reloder-50 | <<locked>> | 98% | 56,420 psi | 85% | 3366 fps | 97.6% |
| Baschieri & Pellagri 109 | <<locked>> | 88% | 58,030 psi | 87% | 3327 fps | 98.5% |
| Bofors RP15 | <<locked>> | 88% | 57,653 psi | 86% | 3360 fps | 100% |
| Bofors RP30 | <<locked>> | 92% | 57,232 psi | 86% | 3366 fps | 99.9% |
| Bofors RP5 | <<locked>> | 86% | 58,291 psi | 87% | 3369 fps | 100% |
| Hodgdon H1000 | <<locked>> | 92% | 58,653 psi | 88% | 3376 fps | 100% |
| Hodgdon H4831 | <<locked>> | 84% | 56,347 psi | 84% | 3301 fps | 99.4% |
| Hodgdon H4831 SC | <<locked>> | 86% | 59,248 psi | 89% | 3346 fps | 99.7% |
| Hodgdon Hybrid 100V | <<locked>> | 82% | 58,755 psi | 88% | 3255 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 90% | 56,869 psi | 85% | 3445 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 37,782 psi | 57% | 2201 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 86% | 60,176 psi | 90% | 3337 fps | 99.8% |
| IMR 7828 SSC | <<locked>> | 88% | 60,278 psi | 90% | 3425 fps | 99.9% |
| IMR 8133 Enduronᴾ | <<locked>> | 100% | 59,770 psi | 90% | 3419 fps | 100% |
| Lovex S071 | <<locked>> | 92% | 59,886 psi | 90% | 3291 fps | 100% |
| Norma 217 | <<locked>> | 98% | 57,305 psi | 86% | 3379 fps | 100% |
| Norma MRP | <<locked>> | 84% | 58,465 psi | 88% | 3386 fps | 100% |
| Ramshot Grand | <<locked>> | 86% | 57,827 psi | 87% | 3383 fps | 99.9% |
| Ramshot Magnum | <<locked>> | 88% | 56,376 psi | 85% | 3297 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 38,798 psi | 58% | 2251 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 90% | 58,189 psi | 87% | 3428 fps | 100% |
| ReloadSwiss RS 80 | <<locked>> | 92% | 57,305 psi | 86% | 3386 fps | 99.5% |
| Rottweil R 904 | <<locked>> | 84% | 59,016 psi | 88% | 3327 fps | 99.9% |
| Rottweil R 905 | <<locked>> | 84% | 58,117 psi | 87% | 3340 fps | 100% |
| SNPE Vectan SP 13ᴾ | <<locked>> | 100% | 52,112 psi | 78% | 3219 fps | 96.3% |
| SNPE Vectan Tubal 8000 | <<locked>> | 84% | 57,740 psi | 87% | 3333 fps | 100% |
| Somchem S361 | <<locked>> | 82% | 56,768 psi | 85% | 3248 fps | 99.5% |
| Somchem S385 | <<locked>> | 84% | 58,508 psi | 88% | 3301 fps | 100% |
| Vihtavuori N165 | <<locked>> | 88% | 58,711 psi | 88% | 3287 fps | 100% |
| Vihtavuori N170 | <<locked>> | 92% | 58,508 psi | 88% | 3314 fps | 97.1% |
| Vihtavuori N555 | <<locked>> | 84% | 58,059 psi | 87% | 3304 fps | 100% |
| Vihtavuori N560 | <<locked>> | 84% | 57,696 psi | 86% | 3389 fps | 99.6% |
| Vihtavuori N565 | <<locked>> | 90% | 59,379 psi | 89% | 3383 fps | 99.8% |
| Vihtavuori N568 | <<locked>> | 92% | 57,522 psi | 86% | 3392 fps | 99.2% |
| Vihtavuori N570 | <<locked>> | 94% | 59,146 psi | 89% | 3465 fps | 98.2% |
| Winchester StaBALL HD | <<locked>> | 86% | 57,522 psi | 86% | 3366 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 86% | 58,624 psi | 88% | 3297 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% | 47,195 psi | 71% | 3081 fps | 100% |
| Accurate 8700 | <<locked>> | 98% | 46,383 psi | 70% | 3123 fps | 95% |
| Accurate MAGPRO | <<locked>> | 80% | 49,443 psi | 74% | 3232 fps | 98.1% |
| ADI AR 2209 | <<locked>> | 80% | 51,314 psi | 77% | 3232 fps | 99.7% |
| ADI AR 2213 | <<locked>> | 80% | 46,630 psi | 70% | 3169 fps | 98.4% |
| ADI AR 2217 | <<locked>> | 82% | 37,231 psi | 56% | 2936 fps | 96.1% |
| ADI AR 2218 | 104.8 gr | 92% | 46,441 psi | 70% | 3232 fps | 95.6% |
| ADI AR 2225 | <<locked>> | 80% | 32,111 psi | 48% | 2831 fps | 97% |
| Alliant Reloder-19 | <<locked>> | 80% | 51,024 psi | 76% | 3219 fps | 99.7% |
| Alliant Reloder-22 | <<locked>> | 80% | 47,398 psi | 71% | 3169 fps | 99.3% |
| Alliant Reloder-23 | <<locked>> | 80% | 46,093 psi | 69% | 3097 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 80% | 40,263 psi | 60% | 3031 fps | 99.9% |
| Alliant Reloder-26 | <<locked>> | 80% | 53,214 psi | 80% | 3291 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 90% | 48,196 psi | 72% | 3222 fps | 96.1% |
| Alliant Reloder-50 | <<locked>> | 94% | 48,457 psi | 73% | 3209 fps | 95.6% |
| Baschieri & Pellagri 109 | <<locked>> | 80% | 44,469 psi | 67% | 3061 fps | 95.3% |
| Bofors RP15 | <<locked>> | 80% | 44,034 psi | 66% | 3097 fps | 98.7% |
| Bofors RP30 | <<locked>> | 80% | 37,565 psi | 56% | 2953 fps | 96.2% |
| Bofors RP5 | <<locked>> | 80% | 47,398 psi | 71% | 3169 fps | 99.3% |
| Hodgdon H1000 | <<locked>> | 80% | 37,898 psi | 57% | 2956 fps | 97% |
| Hodgdon H4831 | <<locked>> | 80% | 48,979 psi | 73% | 3163 fps | 98.4% |
| Hodgdon H4831 SC | <<locked>> | 80% | 48,196 psi | 72% | 3146 fps | 98.2% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 55,143 psi | 83% | 3202 fps | 100% |
| Hodgdon Retumbo | 86 gr | 80% | 39,305 psi | 59% | 3081 fps | 98.5% |
| Hodgdon TrailBoss | <<locked>> | 80% | 28,369 psi | 43% | 1978 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 80% | 49,588 psi | 74% | 3150 fps | 98.6% |
| IMR 7828 SSC | <<locked>> | 80% | 45,353 psi | 68% | 3146 fps | 98.2% |
| IMR 8133 Enduron | <<locked>> | 86% | 36,796 psi | 55% | 2943 fps | 95.7% |
| Lovex S071 | <<locked>> | 80% | 40,640 psi | 61% | 2943 fps | 99.6% |
| Norma 217 | <<locked>> | 82% | 32,198 psi | 48% | 2828 fps | 96% |
| Norma MRP | <<locked>> | 80% | 50,763 psi | 76% | 3251 fps | 100% |
| Ramshot Grand | <<locked>> | 80% | 45,963 psi | 69% | 3163 fps | 98.6% |
| Ramshot Magnum | <<locked>> | 80% | 41,597 psi | 62% | 3018 fps | 99% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 29,196 psi | 44% | 2024 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 80% | 39,117 psi | 59% | 3054 fps | 99.3% |
| ReloadSwiss RS 80 | 95.1 gr | 82% | 38,914 psi | 58% | 2999 fps | 95% |
| Rottweil R 904 | <<locked>> | 80% | 51,663 psi | 77% | 3196 fps | 99.2% |
| Rottweil R 905 | <<locked>> | 80% | 50,836 psi | 76% | 3212 fps | 99.7% |
| SNPE Vectan SP 13 | <<locked>> | 98% | 48,559 psi | 73% | 3150 fps | 95.2% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 50,488 psi | 76% | 3205 fps | 99.7% |
| Somchem S361 | <<locked>> | 80% | 53,026 psi | 79% | 3182 fps | 99.1% |
| Somchem S385 | <<locked>> | 80% | 51,242 psi | 77% | 3179 fps | 99.9% |
| Vihtavuori N165 | <<locked>> | 80% | 44,831 psi | 67% | 3038 fps | 99.3% |
| Vihtavuori N170 | <<locked>> | 88% | 50,908 psi | 76% | 3173 fps | 95.3% |
| Vihtavuori N555 | <<locked>> | 80% | 50,894 psi | 76% | 3186 fps | 100% |
| Vihtavuori N560 | <<locked>> | 80% | 50,183 psi | 75% | 3248 fps | 98.7% |
| Vihtavuori N565 | <<locked>> | 80% | 41,930 psi | 63% | 3041 fps | 96.9% |
| Vihtavuori N568 | <<locked>> | 84% | 42,917 psi | 64% | 3094 fps | 95.9% |
| Vihtavuori N570 | <<locked>> | 88% | 47,413 psi | 71% | 3232 fps | 95.3% |
| Winchester StaBALL HD | <<locked>> | 80% | 45,571 psi | 68% | 3166 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 80% | 47,456 psi | 71% | 3104 fps | 99.3% |
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 58 powders for 7.21 Firebird loaded with the .284 | 130gr | Speer Soft Point. ADI AR 2218 delivers the highest muzzle velocity at 3,481 fps; across all powders the maximum-charge window runs from 2,201 fps to 3,481 fps. Accurate 8700 gives the best case fill at 100 %, and 58 of the 58 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 130.0 gr projectile in 0.284" calls for a 1:14.0 twist; slower twists will usually not stabilise this weight. Accurate 8700, Hodgdon TrailBoss, Hodgdon US 869 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, ADI AR 2218, ReloadSwiss RS 80 rank at the top here: for 7.21 Firebird with the .284 | 130gr | Speer Soft Point they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, Hodgdon US 869, Lovex D100, Ramshot LRT 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.