Load Specifications
Load data in caliber .338 ARC with .338 | 250gr | A-Square MONO RN bullet and 20 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are ADI AR 2207, Norma 200 and Alliant Reloder-7.
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: 16"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 1680 | <<locked>> | 92% | 45,324 psi | 87% | 1657 fps | 98.1% |
| ADI AR 2205 | <<locked>> | 84% | 46,354 psi | 89% | 1591 fps | 100% |
| ADI AR 2207 | <<locked>> | 98% | 45,252 psi | 87% | 1716 fps | 100% |
| Alliant Reloder-10xᴾ | <<locked>> | 100% | 39,653 psi | 76% | 1670 fps | 97.4% |
| Alliant Reloder-7 | <<locked>> | 96% | 45,281 psi | 87% | 1686 fps | 98.7% |
| Baschieri & Pellagri 106ᴾ | <<locked>> | 100% | 45,455 psi | 87% | 1670 fps | 95.7% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 29,515 psi | 57% | 994 fps | 100% |
| IMR 4198ᴾ | <<locked>> | 100% | 43,627 psi | 84% | 1670 fps | 98.8% |
| IMR 4227 | <<locked>> | 90% | 45,368 psi | 87% | 1647 fps | 99.7% |
| Lovex D060 | <<locked>> | 84% | 46,702 psi | 90% | 1670 fps | 99.1% |
| Lovex S053 | <<locked>> | 92% | 46,630 psi | 90% | 1654 fps | 100% |
| Norma 200ᴾ | <<locked>> | 100% | 44,860 psi | 86% | 1722 fps | 98.9% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 29,283 psi | 56% | 1020 fps | 100% |
| ReloadSwiss RS 36 | <<locked>> | 92% | 46,760 psi | 90% | 1693 fps | 99.8% |
| Shooters World Buffalo Rifle | <<locked>> | 84% | 46,702 psi | 90% | 1670 fps | 99.1% |
| Shooters World SOCOM | <<locked>> | 84% | 46,760 psi | 90% | 1657 fps | 99.4% |
| SNPE Vectan BA6 1/2 | <<locked>> | 94% | 45,368 psi | 87% | 1549 fps | 100% |
| Vihtavuori N110 | <<locked>> | 86% | 46,702 psi | 90% | 1601 fps | 100% |
| Vihtavuori N120 | <<locked>> | 98% | 45,513 psi | 88% | 1690 fps | 100% |
| Vihtavuori N130ᴾ | <<locked>> | 100% | 38,595 psi | 74% | 1611 fps | 96.6% |
Recommended = one of the top powders for this cartridge and bullet combination.
Start Load - Barrel Length: 16"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 1680 | <<locked>> | 82% | 32,822 psi | 63% | 1496 fps | 95% |
| ADI AR 2205 | <<locked>> | 80% | 41,234 psi | 79% | 1539 fps | 100% |
| ADI AR 2207 | 17.8 gr | 80% | 26,397 psi | 51% | 1450 fps | 97.1% |
| Alliant Reloder-10x | <<locked>> | 94% | 32,880 psi | 63% | 1575 fps | 95.4% |
| Alliant Reloder-7 | 19.4 gr | 84% | 31,923 psi | 61% | 1509 fps | 95.6% |
| Baschieri & Pellagri 106 | <<locked>> | 98% | 42,801 psi | 82% | 1637 fps | 95% |
| Hodgdon TrailBoss | <<locked>> | 80% | 21,625 psi | 42% | 886 fps | 100% |
| IMR 4198 | <<locked>> | 88% | 31,314 psi | 60% | 1496 fps | 95.5% |
| IMR 4227 | <<locked>> | 80% | 33,721 psi | 65% | 1499 fps | 98.1% |
| Lovex D060 | <<locked>> | 80% | 41,524 psi | 80% | 1604 fps | 98.3% |
| Lovex S053 | <<locked>> | 80% | 33,069 psi | 64% | 1490 fps | 99.8% |
| Norma 200 | 20 gr | 86% | 29,095 psi | 56% | 1506 fps | 95% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 21,161 psi | 41% | 906 fps | 100% |
| ReloadSwiss RS 36 | <<locked>> | 80% | 32,460 psi | 62% | 1512 fps | 97.6% |
| Shooters World Buffalo Rifle | <<locked>> | 80% | 41,524 psi | 80% | 1604 fps | 98.3% |
| Shooters World SOCOM | <<locked>> | 80% | 41,017 psi | 79% | 1591 fps | 98.7% |
| SNPE Vectan BA6 1/2 | <<locked>> | 80% | 31,212 psi | 60% | 1391 fps | 100% |
| Vihtavuori N110 | <<locked>> | 80% | 38,943 psi | 75% | 1519 fps | 100% |
| Vihtavuori N120 | <<locked>> | 80% | 26,789 psi | 52% | 1437 fps | 98.3% |
| Vihtavuori N130 | <<locked>> | 96% | 34,360 psi | 66% | 1552 fps | 95.4% |
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 20 powders for .338 ARC loaded with the .338 | 250gr | A-Square MONO RN. Norma 200 delivers the highest muzzle velocity at 1,722 fps; across all powders the maximum-charge window runs from 994 fps to 1,722 fps. Alliant Reloder-10x gives the best case fill at 100 %, and 20 of the 20 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (359 MPa), the top charges use 56–90 %, leaving at least 10 % headroom. Alliant Reloder-10x, Baschieri & Pellagri 106, Hodgdon TrailBoss 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 2207, Norma 200, Alliant Reloder-7 rank at the top here: for .338 ARC with the .338 | 250gr | A-Square MONO RN they combine a high case fill with complete burn and sit in the upper velocity band. Hodgdon TrailBoss, ReloadSwiss RS 14 stay subsonic at start load. Always begin at the start load and work up in small increments while checking case and primer for pressure signs.