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Lindcott Armory

Hodgdon Powder Company · Extruded

IMR 7977

Enduron series very slow magnum powder.

Manufacturer
IMR
Grain shape
Extruded
Burn rank
#80
Category
Medium-Slow
Temp sensitivity
Low
Application
Rifle
Origin
USA
Status
Discontinued

Burn-rate position

FastestSlowest

Rank #80 on the burn-rate scale · Medium-Slow

Typical cartridges

.28 Nosler, .416 Remington Magnum, 7mm PRC, 6.5-300 Weatherby Magnum, .338 Remington Ultra Magnum, .300 PRC, .26 Nosler, 6.5 PRC, .30 Nosler, .300 Winchester Magnum, .338 Norma Magnum, 7mm Remington Magnum, .338 Lapua Magnum, .300 WSM

Substitutes

Listed substitutions with charge guidance. Always start at published minimums and work up.

H1000 · Hodgdon Published

ADI-based Enduron powder; very similar burn rate to H1000. Use published data for each powder.

By cartridge

.28 Nosler also used: Reloader 26, IMR 8133
.416 Remington Magnum also used: 203-B, Norma 202, Norma 204
7mm PRC also used: N555, N560, Vihtavuori N160
6.5-300 Weatherby Magnum also used: N170, Reloader 25, Reloader 26
.338 Remington Ultra Magnum also used: N170, Reloader 25, Reloader 26
.300 PRC also used: N550, N555, N560
.26 Nosler also used: N165, Reloader 23, Reloader 26
6.5 PRC also used: N550, N555, StaBALL Match
.30 Nosler also used: N165, N170, Reloader 26
.300 Winchester Magnum also used: N550, Superperformance, N555
.338 Norma Magnum also used: URP, Norma MRP, N165
7mm Remington Magnum also used: Superperformance, D072.5, IMR 4320

Similar burn rate

#80Accurate 3100Accurate #80LRTRamshot #79IMR 5010IMR #79Reloader 26Alliant #78RetumboHodgdon

Supply & handling

Availability (US)
Common
Shortage-prone
No
Suppressor-friendly
Yes
Flash-suppressed
No

About this powder

IMR 7977 is the slowest of the standard Enduron series powders, designed for ultra-magnum rifle cartridges including .338 Lapua and .300 Norma Mag. Long-range hunters and precision competitors benefit from its temperature stability when velocity consistency across diurnal temperature swings matters at distance.

Head-to-headIMR 7977 vs H1000Head-to-headIMR 7977 vs Reloader 26 ChartSee it on the burn-rate spectrum BrowseEvery powder, ranked by burn rate

Sources & provenance