Load Specifications
Load data in caliber .450 Marlin with .458 | 270gr | Atomic 29 FNHP bullet and 12 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Accurate No. 11 FS, Vihtavuori N110 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.
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Max Load - Barrel Length: 24"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate No. 11 FS | <<locked>> | 90% | 43,192 psi | 90% | 2336 fps | 98.1% |
| ADI AR 2205 | <<locked>> | 92% | 43,308 psi | 90% | 2260 fps | 99.3% |
| Hodgdon LilGun | <<locked>> | 86% | 42,467 psi | 89% | 2395 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 25,570 psi | 53% | 1401 fps | 100% |
| IMR 4227ᴾ | <<locked>> | 100% | 42,975 psi | 90% | 2329 fps | 96.5% |
| Lovex S040 | <<locked>> | 84% | 42,453 psi | 89% | 2247 fps | 100% |
| Lovex S053ᴾ | <<locked>> | 100% | 39,885 psi | 83% | 2306 fps | 99% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 24,584 psi | 51% | 1434 fps | 100% |
| ReloadSwiss RS 36ᴾ | <<locked>> | 100% | 40,596 psi | 85% | 2343 fps | 95.8% |
| SNPE Vectan BA6 1/2ᴾ | <<locked>> | 100% | 37,217 psi | 78% | 2169 fps | 100% |
| Vihtavuori N110 | <<locked>> | 96% | 42,467 psi | 89% | 2303 fps | 100% |
| Vihtavuori N120ᴾ | <<locked>> | 100% | 32,169 psi | 67% | 2211 fps | 96.3% |
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 | 41.8 gr | 82% | 33,315 psi | 70% | 2165 fps | 95.7% |
| ADI AR 2205 | <<locked>> | 80% | 30,182 psi | 63% | 2024 fps | 96.6% |
| Hodgdon LilGun | <<locked>> | 80% | 34,272 psi | 72% | 2267 fps | 100% |
| Hodgdon TrailBoss | <<locked>> | 80% | 18,434 psi | 39% | 1250 fps | 100% |
| IMR 4227 | <<locked>> | 96% | 38,218 psi | 80% | 2247 fps | 95.3% |
| Lovex S040 | <<locked>> | 80% | 37,826 psi | 79% | 2175 fps | 100% |
| Lovex S053 | 38 gr | 86% | 26,614 psi | 56% | 2037 fps | 95.3% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 17,680 psi | 37% | 1276 fps | 100% |
| ReloadSwiss RS 36 | <<locked>> | 98% | 38,116 psi | 80% | 2300 fps | 95.1% |
| SNPE Vectan BA6 1/2 | <<locked>> | 80% | 21,640 psi | 45% | 1850 fps | 99.4% |
| Vihtavuori N110 | 33.8 gr | 80% | 26,498 psi | 55% | 2018 fps | 99.5% |
| Vihtavuori N120 | <<locked>> | 98% | 30,385 psi | 63% | 2172 fps | 95.7% |
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 21 powders for .450 Marlin loaded with the .458 | 270gr | Atomic 29 FNHP. Hodgdon LilGun delivers the highest muzzle velocity at 2,395 fps; across all powders the maximum-charge window runs from 1,401 fps to 2,395 fps. Accurate 1680 gives the best case fill at 100 %, and 21 of the 21 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (330 MPa), the top charges use 51–90 %, leaving at least 10 % headroom. Accurate 1680, ADI AR 2207, Alliant Reloder-7 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 No. 11 FS, Vihtavuori N110, Lovex S053 rank at the top here: for .450 Marlin with the .458 | 270gr | Atomic 29 FNHP they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, Accurate 1680, Accurate 5744, ADI AR 2207 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.