.338-375 AI (.338-375 Ackley Improved) is one of 607 cartridges supported by the IBC calculator. Pick a load from your reloading manual, enter it, and the calculator predicts velocity and peak pressure, then gives a verdict against the cartridge's pressure ceiling. It is a comparison tool for working between loads you already trust, not a source of load data.
| Max average pressure | 4,300 bar ≈ 62,350 psi |
|---|---|
| Case capacity (water) | 98.8 gr H₂O (6.40 cm³) |
| Case length | 72.6 mm (2.860″) |
| Max overall length | 94.3 mm (3.714″) |
| Bore diameter | 9.550 mm (0.376″) |
| Standard | WildCat |
Catalogued reference values the calculator works from. No charge, velocity, or pressure data appears on this page; loads come from your manual.
.338-375 AI (.338-375 Ackley Improved) is fully supported in the calculator, but the current published validation corpus has no .338-375 AI (.338-375 Ackley Improved) loads in it yet, so IBC prints no per-cartridge accuracy figure here. Per-cartridge numbers on this site appear only where the corpus actually contains loads for that cartridge. The corpus-wide results and the method behind them are on the methodology page.
Open the calculator, pick .338-375 AI (.338-375 Ackley Improved) from the cartridge list, and enter a load from your current reloading manual. Compare variants: bullet weights, powders, charge steps. Start 10% below the manual's maximum charge and work up, watch the verdict on every rung, and check real pressure signs at the bench. The free tier covers single-load predictions and the first steps of a work-up ladder; PRO unlocks the full ladder and the charts.
Open the calculatorAccuracy figures on this page were computed from the published-manual validation corpus (9796 loads across 155 cartridges) with engine v1.1.14 (corpus build da7ac091). Page generated 2026-11-11. Method and provenance: methodology & accuracy.