Load Specifications
Load data in caliber .338 ARC with .338 | 300gr | MAKER .338 ARC/Spectre Expanding Subsonic bullet and 19 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Shooters World Buffalo Rifle, Lovex D060 and Shooters World SOCOM.
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: 16"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 5744 | <<locked>> | 86% | 46,296 psi | 89% | 1306 fps | 97.3% |
| Accurate No. 11 FS | <<locked>> | 90% | 46,470 psi | 89% | 1306 fps | 99.6% |
| ADI AR 2205 | <<locked>> | 92% | 46,151 psi | 89% | 1257 fps | 100% |
| ADI AR 2207ᴾ | <<locked>> | 100% | 34,418 psi | 66% | 1260 fps | 97.8% |
| Hodgdon LilGun | <<locked>> | 86% | 46,470 psi | 89% | 1329 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 26,498 psi | 51% | 748 fps | 100% |
| IMR 4227ᴾ | <<locked>> | 100% | 46,151 psi | 89% | 1302 fps | 98.6% |
| Lovex D060 | <<locked>> | 92% | 46,296 psi | 89% | 1306 fps | 97.3% |
| Lovex D063 | <<locked>> | 88% | 44,802 psi | 86% | 1293 fps | 97% |
| Lovex S040 | <<locked>> | 84% | 45,556 psi | 88% | 1240 fps | 100% |
| Lovex S053ᴾ | <<locked>> | 100% | 42,859 psi | 82% | 1286 fps | 99.9% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 25,802 psi | 50% | 764 fps | 100% |
| ReloadSwiss RS 36ᴾ | <<locked>> | 100% | 43,366 psi | 83% | 1312 fps | 98.1% |
| Shooters World Blackout | <<locked>> | 88% | 44,802 psi | 86% | 1293 fps | 97% |
| Shooters World Buffalo Rifle | <<locked>> | 92% | 46,296 psi | 89% | 1306 fps | 97.3% |
| Shooters World SOCOM | <<locked>> | 92% | 45,600 psi | 88% | 1293 fps | 97.6% |
| SNPE Vectan BA6 1/2ᴾ | <<locked>> | 100% | 39,856 psi | 77% | 1194 fps | 100% |
| Vihtavuori N110 | <<locked>> | 96% | 45,672 psi | 88% | 1270 fps | 100% |
| Vihtavuori N120ᴾ | <<locked>> | 100% | 35,070 psi | 67% | 1247 fps | 98.8% |
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 5744 | <<locked>> | 80% | 38,305 psi | 74% | 1230 fps | 95.4% |
| Accurate No. 11 FS | <<locked>> | 80% | 33,721 psi | 65% | 1188 fps | 97.6% |
| ADI AR 2205 | <<locked>> | 80% | 32,082 psi | 62% | 1125 fps | 98.7% |
| ADI AR 2207 | <<locked>> | 92% | 27,311 psi | 53% | 1168 fps | 95.3% |
| Hodgdon LilGun | <<locked>> | 80% | 37,956 psi | 73% | 1263 fps | 100% |
| Hodgdon TrailBoss | <<locked>> | 80% | 19,740 psi | 38% | 669 fps | 100% |
| IMR 4227 | <<locked>> | 88% | 32,547 psi | 63% | 1171 fps | 95.6% |
| Lovex D060 | 11.3 gr | 84% | 36,738 psi | 71% | 1214 fps | 95% |
| Lovex D063 | <<locked>> | 82% | 36,970 psi | 71% | 1217 fps | 95.1% |
| Lovex S040 | <<locked>> | 80% | 40,683 psi | 78% | 1201 fps | 100% |
| Lovex S053 | <<locked>> | 80% | 24,497 psi | 47% | 1079 fps | 96.5% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 19,377 psi | 37% | 689 fps | 100% |
| ReloadSwiss RS 36 | <<locked>> | 90% | 32,300 psi | 62% | 1201 fps | 95.4% |
| Shooters World Blackout | <<locked>> | 82% | 36,970 psi | 71% | 1217 fps | 95.1% |
| Shooters World Buffalo Rifle | 11.3 gr | 84% | 36,738 psi | 71% | 1214 fps | 95% |
| Shooters World SOCOM | 12.6 gr | 84% | 35,317 psi | 68% | 1198 fps | 95.3% |
| SNPE Vectan BA6 1/2 | <<locked>> | 80% | 23,511 psi | 45% | 1024 fps | 100% |
| Vihtavuori N110 | <<locked>> | 80% | 29,457 psi | 57% | 1125 fps | 100% |
| Vihtavuori N120 | <<locked>> | 88% | 24,700 psi | 47% | 1112 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 19 powders for .338 ARC loaded with the .338 | 300gr | MAKER .338 ARC/Spectre Expanding Subsonic. Hodgdon LilGun delivers the highest muzzle velocity at 1,329 fps; across all powders the maximum-charge window runs from 748 fps to 1,329 fps. ADI AR 2207 gives the best case fill at 100 %, and 19 of the 19 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (359 MPa), the top charges use 50–89 %, leaving at least 11 % headroom. The 300.0 gr projectile in 0.338" calls for a 1:11.5 twist; slower twists will usually not stabilise this weight. ADI AR 2207, Hodgdon TrailBoss, IMR 4227 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. Shooters World Buffalo Rifle, Lovex D060, Shooters World SOCOM rank at the top here: for .338 ARC with the .338 | 300gr | MAKER .338 ARC/Spectre Expanding Subsonic they combine a high case fill with complete burn and sit in the upper velocity band. Hodgdon TrailBoss, Lovex S053, 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.