Load Specifications
Load data in caliber .221 Rem. Fireball with .224 | 55gr | Hornady GMX bullet and 15 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are ReloadSwiss RS 36, ADI AR 2207 and Lovex S053.
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: 24"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate No. 11 FS | <<locked>> | 82% | 41,655 psi | 90% | 2694 fps | 99.1% |
| ADI AR 2205 | <<locked>> | 84% | 41,220 psi | 89% | 2608 fps | 99.8% |
| ADI AR 2207ᴾ | <<locked>> | 100% | 41,205 psi | 89% | 2805 fps | 99.1% |
| Alliant Reloder-7 | <<locked>> | 98% | 41,452 psi | 89% | 2743 fps | 96.2% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 27,934 psi | 60% | 1726 fps | 100% |
| IMR 4227 | <<locked>> | 92% | 41,959 psi | 90% | 2707 fps | 98% |
| Lovex D060 | <<locked>> | 84% | 41,669 psi | 90% | 2713 fps | 96.3% |
| Lovex S053 | <<locked>> | 92% | 39,813 psi | 86% | 2677 fps | 99.7% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 27,093 psi | 58% | 1762 fps | 100% |
| ReloadSwiss RS 36 | <<locked>> | 92% | 40,408 psi | 87% | 2723 fps | 97.6% |
| Shooters World Buffalo Rifle | <<locked>> | 84% | 41,669 psi | 90% | 2713 fps | 96.3% |
| Shooters World SOCOM | <<locked>> | 84% | 40,930 psi | 88% | 2671 fps | 96.9% |
| SNPE Vectan BA6 1/2 | <<locked>> | 96% | 41,423 psi | 89% | 2582 fps | 100% |
| Vihtavuori N110 | <<locked>> | 88% | 41,916 psi | 90% | 2661 fps | 100% |
| Vihtavuori N120ᴾ | <<locked>> | 100% | 41,640 psi | 90% | 2769 fps | 99.7% |
Recommended = one of the top powders for this cartridge and bullet combination.
Start Load - Barrel Length: 24"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate No. 11 FS | <<locked>> | 80% | 39,334 psi | 85% | 2651 fps | 98.7% |
| ADI AR 2205 | <<locked>> | 80% | 36,709 psi | 79% | 2520 fps | 99.4% |
| ADI AR 2207 | 13.8 gr | 88% | 28,268 psi | 61% | 2510 fps | 95.5% |
| Alliant Reloder-7 | <<locked>> | 96% | 39,102 psi | 84% | 2700 fps | 95.5% |
| Hodgdon TrailBoss | <<locked>> | 80% | 19,798 psi | 43% | 1532 fps | 100% |
| IMR 4227 | <<locked>> | 84% | 32,996 psi | 71% | 2520 fps | 95.6% |
| Lovex D060 | <<locked>> | 82% | 39,334 psi | 85% | 2664 fps | 95.7% |
| Lovex S053 | 12 gr | 80% | 27,833 psi | 60% | 2405 fps | 97.3% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 19,305 psi | 42% | 1568 fps | 100% |
| ReloadSwiss RS 36 | 14 gr | 86% | 33,214 psi | 72% | 2572 fps | 95.6% |
| Shooters World Buffalo Rifle | <<locked>> | 82% | 39,334 psi | 85% | 2664 fps | 95.7% |
| Shooters World SOCOM | <<locked>> | 80% | 35,752 psi | 77% | 2562 fps | 95.4% |
| SNPE Vectan BA6 1/2 | <<locked>> | 80% | 26,600 psi | 57% | 2290 fps | 100% |
| Vihtavuori N110 | <<locked>> | 80% | 33,257 psi | 72% | 2503 fps | 100% |
| Vihtavuori N120 | <<locked>> | 84% | 25,570 psi | 55% | 2395 fps | 95.5% |
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 15 powders for .221 Rem. Fireball loaded with the .224 | 55gr | Hornady GMX. ADI AR 2207 delivers the highest muzzle velocity at 2,805 fps; across all powders the maximum-charge window runs from 1,726 fps to 2,805 fps. ADI AR 2207 gives the best case fill at 100 %, and 15 of the 15 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (320 MPa), the top charges use 58–90 %, leaving at least 10 % headroom. The 55.0 gr projectile in 0.224" calls for a 1:10.5 twist; slower twists will usually not stabilise this weight. ADI AR 2207, 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. ReloadSwiss RS 36, ADI AR 2207, Lovex S053 rank at the top here: for .221 Rem. Fireball with the .224 | 55gr | Hornady GMX 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.