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
Typical cartridges
Substitutes
Listed substitutions with charge guidance. Always start at published minimums and work up.
H1000 · HodgdonPublished
ADI-based Enduron powder; very similar burn rate to H1000. Use published data for each powder.
By cartridge
.300 Winchester Magnumalso used: Superperformance, N560, Norma 204
.300 WSMalso used: Alliant Reloader 16, Reloader 17, IMR 4955
.338 Lapua Magnumalso used: MRP2, S365, AR 2217
.28 Nosleralso used: Reloader 26, IMR 8133
6.5 PRCalso used: StaBALL Match, Reloader 17, IMR 4955
7mm Remington Magnumalso used: Superperformance, D072.5, IMR 4320
.416 Remington Magnumalso used: N165, AR 2218, N170
.338 Remington Ultra Magnumalso used: N170, Reloader 25, Reloader 26
.26 Nosleralso used: N165, Reloader 23, Reloader 26
.338 Norma Magnumalso used: N165, AR 2218, N170
Similar burn rate
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.