IMR Enduron
IMR Enduron 4955
A slower match-grade Enduron powder aimed at big-game cartridges with heavier bullets. Hodgdon states it performs comparably to Hodgdon H4831 with materially different charge weights.
Specifications
| Manufacturer | IMR |
|---|---|
| Product family | IMR Enduron |
| Status | Currently produced |
| Application | rifle |
| Grain form | extruded |
| Composition | single-base |
| Temperature stable | Yes — claimed by the manufacturer |
| Burn-rate position | 168 of 198 (fastest = 1) — what this means |
| Typical cartridges | 25-06 Remington, 270 Winchester, 280 Remington, 300 Winchester Magnum |
Enduron powders are marketed on four shared claims: a copper fouling eliminator additive, reduced sensitivity to temperature change, loading density matched to the intended cartridge class, and a REACH-compliant formulation. Extruded single-base, made in Canada.
Burn rate
Slow; between IMR Enduron 4451 and IMR Enduron 7977, and near Hodgdon H4831.
Chart agreement: consistent across the three charts that list it Ranked by: Hodgdon, Vihtavuori, Wolfe/LoadData.
Powders charted near it — neighbours on the chart are not substitutes, and adjacency tells you nothing about what charge either one takes:
- Hodgdon H4831 (position 166)
- Hodgdon H4831SC (position 166)
- Vihtavuori N560 (position 167)
- Norma MRP (position 169)
- Alliant Reloder 22 (position 170)
- Norma MRP-2 (position 171)
Sources
Other IMR powders
Verify the charge, not just the recipe
Good data gets you a safe starting point. It does not tell you what actually went into the case on stroke 340 — a bridged measure, a double charge, a squib. That is what an RCM Laser Powder Check is for.