Within the hierarchy of legendary propellants, IMR 4064 holds a position of nearly unrivaled respect as one of the most versatile and accurate medium-burn powders ever produced. For generations, it has been the standard by which other powders in the 308 Winchester and 30-06 Springfield classes are measured. Its reputation for exceptional accuracy across a staggering variety of calibers has made it a permanent fixture on the benches of competitive marksmen and serious hunters alike.
Whether you are seeking the absolute smallest group sizes in a bolt-action target rifle or developing a reliable hunting load for a classic medium-bore cartridge, IMR 4064 provides a stable, high-performance platform. This guide explores the technical profile, comparative performance, and component pairings for this quintessential “accuracy powder.”
Executive Summary
- Main Application: Medium-capacity rifle cartridges, specifically those used in precision target shooting and big game hunting.
- Key Advantage: Exceptional inherent accuracy and a wide “sweet spot” for load development.
- Burn Rate: Medium rifle propellant, widely considered the gold standard for its burn speed.
- What This Guide Covers: Technical specifications, temperature stability, market comparisons, and comprehensive primer and bullet matching.
Best For: Precision-oriented reloaders, long-range competitors, and hunters using standard .30 caliber cartridges.
Powder Description & Technical Profile
IMR 4064 is a single-base, extruded (stick) propellant. Unlike modern “short-cut” powders, IMR 4064 maintains a traditional longer grain geometry. While this physical characteristic requires more attention during the metering process, it is often credited with providing the consistent ignition and pressure curves that lead to its world-class accuracy.
The Expert “Feel”
Reloaders often describe the performance of IMR 4064 as “predictable.” It is remarkably forgiving during the load development process; small variations in charge weight rarely lead to radical shifts in pressure or accuracy. In the rifle, it provides a firm but smooth recoil impulse and is noted for its ability to produce consistent muzzle velocities even when case fill is not at 100%.
Pros & Cons
- Pros:
- Legendary accuracy potential in a wide variety of calibers.
- Highly versatile, spanning from .223 Remington to [.375 H&H Magnum].
- Forgiving pressure curve that is ideal for bolt-action rifles.
- Excellent ignition characteristics with standard primers.
- Cons:
- Longer grain size makes volumetric metering through standard measures difficult.
- Often requires a powder trickler or digital dispenser for precision.
Technical Characteristics
The physical and chemical composition of IMR 4064 makes it a stable, long-lasting propellant that is easy to store and use.
| Property | Specification |
| Manufacturer | IMR (Improved Military Rifle) |
| Powder Type | Extruded (Stick) |
| Base | Single-Base (Nitrocellulose) |
| Density | 0.910 g/cc |
| Burn Rate Category | Medium Rifle |
| Coating | Technical Graphite Coating |
Temperature Stability & Burn Rate Analysis
While IMR 4064 is a single-base powder—which is inherently more stable than many double-base options—it is a traditional formulation. It does not carry the specific “extreme” temperature-insensitive coatings found in newer lines. Reloaders can expect a moderate shift in muzzle velocity as temperatures fluctuate, typically in the range of 0.6-0.9 FPS per degree Fahrenheit.
For the precision shooter, this means that a load developed in a 65°F environment may see a change in point-of-impact during a 95°F summer match. However, its consistency within a standard temperature range remains excellent, which is why it has remained a top choice for benchrest and long-range shooters for decades.
Stability Benchmark Comparison
| Powder Name | Stability Level | Tech Category |
| IMR 4064 | Moderate | Standard Single-Base |
| Hodgdon Varget | Extreme | Insensitive Extruded |
| Hodgdon BL-C(2) | Standard | Double-Base Spherical |
Powder Comparison
Because IMR 4064 is a market leader, it is frequently compared to other “middle-of-the-road” rifle propellants.
- Hodgdon Varget: The modern rival. While Varget is more temperature-stable and easier to meter, many shooters still find that IMR 4064 produces tighter groups in specific 308 Winchester rifles.
- IMR 4895: Slightly faster than IMR 4064. IMR 4895 is often preferred for semi-autos like the M1 Garand, whereas IMR 4064 is usually the pick for bolt-action precision.
- Alliant Reloder 15: Sits in a very similar burn rate window. Reloder 15 often provides slightly higher top-end velocities, but IMR 4064 is generally considered more “forgiving” near maximum loads.
- Accurate 4064: A newer formulation designed to mimic the performance of the IMR original. Accurate 4064 features slightly shorter grains for better metering.
Competitor Comparison Table
| Powder | Burn Rate | Density (g/cc) | Primary Cartridges |
| IMR 4064 | Medium | 0.910 | 308 Winchester, 30-06 Springfield |
| Hodgdon Varget | Medium | 0.885 | 22-250 Remington, 308 Winchester |
| IMR 4895 | Medium-Fast | 0.890 | 30-06 Springfield (M1), 303 British |
| Alliant Reloder 15 | Medium | 0.925 | 6.5 Creedmoor, 308 Winchester |
| Accurate 4064 | Medium | 0.895 | 308 Winchester, 7mm-08 Remington |
Performance, Metering & Equipment
Metering Consistency
The primary challenge with IMR 4064 is its long-grain structure. In traditional volumetric powder measures, the grains can “bridge” or be cut by the drum, leading to charge variations of up to 0.5 grains. For this reason, it is highly recommended to use a digital dispenser like the RCBS ChargeMaster Supreme or to drop a slightly light charge and use a Frankford Arsenal Powder Trickler to reach the final weight.
Fouling and Cleanliness
IMR 4064 is a clean-burning powder, provided it is used at standard operating pressures. Like most single-base powders, it leaves behind a light, easily removable carbon residue. It does not typically contribute to heavy copper fouling, making it an excellent choice for long shooting sessions at the range.
Recommended Cartridges and Applications
The sheer number of cartridges that perform well with IMR 4064 is a testament to its design. It is effective in everything from small-bore varmint rifles to heavy African calibers.
| Cartridge | Primary Application |
| 308 Winchester | Match-grade accuracy with 150-175 grain bullets |
| 30-06 Springfield | All-purpose hunting with 150-180 grain bullets |
| 22-250 Remington | Precision varmint hunting |
| 243 Winchester | High-velocity deer hunting loads |
| 6.5 Creedmoor | Excellent for 120-130 grain hunting bullets |
| 7.62x54R | Vintage precision with 150-174 grain bullets |
| 223 Remington | Heavy-bullet target loads (69-77 grain) |
Recommended Bullets
To reach the accuracy potential of IMR 4064, pair it with high-BC projectiles or proven hunting designs.
| Bullet Brand/Model | Recommended Weight | Application |
| Sierra MatchKing | 168-175 grain (308) | Precision Competition |
| Nosler Partition | 165-180 grain (30-06) | Big Game Hunting |
| Hornady V-Max | 50-55 grain (22-250) | Varmint Control |
| Barnes TSX | 150 grain (308) | Lead-Free Hunting |
| Sierra Tipped GameKing | 165 grain (30-06) | Long-Range Hunting |
Primers
Because IMR 4064 is easy to ignite, standard large rifle primers are generally sufficient to achieve consistent results.
- CCI 200: The standard workhorse for 308 Winchester development.
- Federal GM210M: Gold Medal Match primer for the lowest velocity spreads.
- Winchester WLR: A reliable, hot primer that ensures excellent ignition in cold weather.
- Remington 9-1-2: A durable option for all hunting applications.
- CCI BR-2: Benchrest primer specifically designed for uniform ignition.
- Federal 210: A very sensitive and consistent standard primer.
- RWS 5341: High-end European primer for extreme precision.
- Fiocchi Large Rifle: A consistent international option for high-volume loading.
- Sellier-Bellot V360587: Reliable large rifle primer with a consistent strike sensitivity.
Expert Verdict
IMR 4064 is a propellant that has stood the test of time because it simply works. While it may not offer the effortless metering of modern spherical powders or the extreme temperature stability of the newest extruded lines, it provides an “accuracy edge” that is difficult to replicate. For the reloader who values group size above all else and doesn’t mind spending an extra few seconds on each charge, IMR 4064 is arguably the best medium-burn powder ever made.
Expert Pro Tip: If you find that IMR 4064 is “crunching” in your powder measure, try using a vibratory powder trickler in conjunction with a digital scale. This avoids the mechanical shearing of the long grains, which can create small amounts of dust and lead to inconsistent burn rates. Absolute uniformity in grain structure is the key to unlocking sub-quarter-MOA groups with this powder.
