IMR 4350 is a popular medium to slow burning extruded smokeless rifle powder produced under the Hodgdon brand umbrella. Reliable IMR 4350 reloading data can be found directly from major component manufacturers including Hodgdon, Nosler, Hornady, Sierra, and Barnes. Handloaders must match IMR 4350 load data to the exact cartridge, bullet weight, and brass specified by the publisher because pressure scales uniquely with each component combination. It is frequently used for mid capacity and magnum cartridges, making it an excellent choice for full power hunting loads. Some of the most popular IMR 4350 cartridges with published data include the .30-06 Springfield, .270 Winchester, 6.5 Creedmoor, and 7mm Remington Magnum. Always consult primary publishers for the most up to date safety limits before assembling any ammunition.
IMR 4350 Reloading Data
| Cartridge | Bullet | Bullet Weight | Published Starting Load | Published Maximum Load | Published Velocity | Barrel Length | Source |
| .30-06 Springfield | Nosler AccuBond | 165 gr | 53.0 gr | 57.0 gr | 2602 to 2832 fps | 24 in | Nosler Load Data |
| .30-06 Springfield | Barnes TTSX BT | 165 gr | 53.0 gr | 57.5 gr | 2627 to 2845 fps | 24 in | Barnes Bullets |
| 6.5 Creedmoor | Barnes TTSX BT | 120 gr | 42.5 gr | 47.2 gr | 2908 to 3221 fps | 24 in | Barnes Bullets |
| 7mm Remington Magnum | Sierra HP | 100 gr | 66.0 gr | 70.5 gr | 3312 to 3569 fps | 24 in | Hodgdon Basic Manual |
Other data
| Cartridge | Appropriate Bullet Weight | IMR 4350 Load Data / Status |
| 17 Ackley Hornet | N/A | Incompatible: Case volume too small |
| 17 Hornet | N/A | Incompatible: Case volume too small |
| 17 Remington Fireball | N/A | Incompatible: Case volume too small |
| 17 Remington | N/A | Incompatible: Case volume too small |
| 204 Ruger | N/A | Incompatible: Case volume too small |
| 22 Hornet | N/A | Incompatible: Case volume too small |
| 22 K Hornet | N/A | Incompatible: Case volume too small |
| 218 Bee | N/A | Incompatible: Case volume too small |
| 221 Fireball | N/A | Incompatible: Case volume too small |
| 222 Remington | N/A | Incompatible: Case volume too small |
| 223 Remington | N/A | Incompatible: Case volume too small |
| 222 Remington Magnum | N/A | Incompatible: Case volume too small |
| 22 PPC | N/A | Incompatible: Burn rate too slow |
| 224 Valkyrie | N/A | Incompatible: Burn rate too slow |
| 22 Nosler | N/A | Incompatible: Burn rate too slow |
| 22 ARC | N/A | Incompatible: Burn rate too slow |
| 22-250 Remington | 55 gr Spitzer | Min: 35.0 gr / Max: 38.5 gr (3,550 fps) |
| 22-250 Remington | 63 gr Spitzer | Min: 34.0 gr / Max: 36.5 gr (3,350 fps) |
| 220 Swift | 50 gr Spitzer | Min: 38.5 gr / Max: 41.5 gr (3,800 fps) |
| 220 Swift | 55 gr Spitzer | Min: 36.5 gr / Max: 40.5 gr (3,650 fps) |
| 22 GT | N/A | No published IMR 4350 data |
| 22 Creedmoor | 75 gr – 80 gr | Wildcat: H4350 data common; verify IMR locally |
| 223 WSSM | 55 gr Spitzer | Min: 42.0 gr / Max: 46.0 gr (3,850 fps) |
| 223 WSSM | 64 gr Power-Point | Min: 40.0 gr / Max: 43.5 gr (3,500 fps) |
| 6 x 45mm (6mm-223) | N/A | Incompatible: Case volume too small |
| 6mm PPC | N/A | Incompatible: Burn rate too slow |
| 6MM ARC | N/A | Incompatible: Burn rate too slow |
| 24 Nosler | N/A | Incompatible: Burn rate too slow |
What Is IMR 4350?
IMR 4350 is an extruded, single base smokeless propellant originally developed for centerfire rifle cartridges. It sits in the medium to slow burning rate category, making it highly effective for cartridges that feature a large case capacity relative to their bore diameter. The powder grains are cut into small cylindrical sticks. While extruded powders do not always meter as smoothly as spherical powders in a mechanical measure, IMR 4350 powder is highly regarded for its consistent ignition and predictable pressure curves. It appears in published data for dozens of cartridges because it provides excellent case fill density and optimal velocities for popular big game hunting rounds.
Understanding IMR 4350 Load Data
Reading a published IMR 4350 load data chart requires strict attention to multiple variables. The starting load represents the lowest safe powder charge recommended by the ballistic laboratory. The maximum published load is the absolute upper limit tested by the manufacturer before pressures exceed standard limits set by SAAMI. Velocity indicates the speed of the bullet as measured in feet per second during the laboratory test. Pressure figures are sometimes provided in PSI or CUP to show exactly how close the load is to the safety ceiling.
Every manual also specifies the exact bullet weight and the barrel length used for testing. The cartridge overall length is published to ensure the bullet is seated to the exact depth used by the ballistic technicians. Load data differs between sources because different laboratories use different lots of powder, different brass cases, and different test barrels.
Bullet Weight And IMR 4350 Data
Published IMR 4350 load recipes change significantly depending on the weight of the bullet. As a general ballistic rule, heavier bullets take up more case volume and create more resistance as they engage the rifling, which increases chamber pressure. Consequently, an IMR 4350 powder charge must be reduced as bullet weight increases.
For example, in the .30-06 Springfield, this powder is commonly matched with 150 grain, 165 grain, and 180 grain bullets. A powder charge deemed safe for a 150 grain bullet might cause a catastrophic overpressure event if loaded directly behind a 180 grain bullet. A powder charge published for one bullet cannot automatically be applied to another bullet, even if they share the identical weight, due to differences in bearing surface and jacket material.
IMR 4350 Velocity
Velocity expectations change drastically depending on the case capacity and bore diameter of the cartridge. According to Barnes Bullets, a 120 grain TTSX BT fired from a 6.5 Creedmoor with a maximum load of 47.2 grains of IMR 4350 achieves a published velocity of 3221 fps from a 24 inch barrel. In contrast, a heavier 165 grain TTSX BT fired from a .30-06 Springfield with 57.5 grains of IMR 4350 reaches 2845 fps from a 24 inch barrel.
The Hodgdon Basic Manual demonstrates that pushing a lightweight 100 grain Sierra HP bullet in the massive 7mm Remington Magnum case requires up to 70.5 grains of IMR 4350 to reach a published velocity of 3569 fps from a 24 inch test barrel. Do not treat the velocity of one cartridge as representative of another.
Barrel Length And IMR 4350 Velocity
Barrel length has a direct impact on the final velocity of any IMR 4350 load. The powder needs time and space to burn and push the projectile down the bore. When a barrel is shorter than the laboratory test barrel, the bullet will exit before the expanding gases can fully accelerate it, resulting in a lower actual muzzle velocity.
The numerical velocity figures published by Nosler and Barnes for the .30-06 Springfield and 6.5 Creedmoor were recorded using 24 inch test barrels. A hunter using a 20 inch barrel will not see the same velocities printed in the manual. The test barrel must always be identified to provide accurate context for the published velocity.
Manufacturer Data vs Independent Testing
There is a stark difference between official manufacturer published load data and independent chronograph testing. Manufacturer data is developed in highly controlled ballistic laboratories using universal receivers and piezo electronic pressure sensors. This ensures that the published powder charges remain strictly within safe pressure specifications.
Independent chronograph testing and user submitted load reports are gathered in the field using consumer firearms. Ballistic calculator estimates are generated by software algorithms rather than live firing. Independently measured results often differ from published figures due to variations in chamber dimensions, ambient temperature, and specific powder lots. Reloaders must always give priority to official, pressure tested manufacturer data.
IMR 4350 Pressure And Safety
Following published IMR 4350 data exactly is a fundamental safety requirement. Starting loads are provided for a reason; working up slowly allows the handloader to monitor their specific firearm for pressure signs. Maximum published loads must never be exceeded under any circumstances.
Pressure specifications can spike dangerously if any single component is altered. Bullet substitutions change the friction profile within the bore. Brass differences alter internal case capacity, meaning military brass often requires reduced powder charges compared to commercial brass. Primer differences can also shift the ignition intensity. Seating a bullet deeper than the specified cartridge overall length decreases internal volume and heavily increases pressure. Furthermore, powder lot variation and extreme ambient temperatures can cause a previously safe load to become dangerous. Never attempt to develop an unpublished recipe or exceed the maximums printed in official manuals.
Best Sources For IMR 4350 Reloading Data
The strongest current sources for verified IMR 4350 reloading data are the component manufacturers themselves.
- Hodgdon Reloading Data Center: As the distributor of IMR powders, Hodgdon provides the most authoritative and comprehensive data. Their online center is constantly updated and rigorously pressure tested.
- Nosler: The IMR 4350 load data Nosler publishes is highly regarded for its detailed component specificity and transparency regarding which loads produced the best accuracy during their live testing.
- Hornady: IMR 4350 load data Hornady publishes covers an immense variety of proprietary bullets across all major calibers.
- Barnes Bullets: Barnes provides excellent data specifically tailored to solid copper monolithic bullets, which generate different friction and pressures than traditional lead core bullets.
- Sierra Bullets: Sierra offers extensive data for target and hunting applications, breaking down powder charges into clear, incremental velocity tiers.
Official manufacturer manuals distinguish themselves from secondary sources by adhering strictly to SAAMI pressure guidelines.
FAQs
Where can I find IMR 4350 reloading data?
Reliable data can be found in printed reloading manuals and official online databases published by Hodgdon, Nosler, Sierra, Hornady, and Barnes.
What cartridges use IMR 4350?
Popular cartridges that utilize this powder include the .243 Winchester, .270 Winchester, .30-06 Springfield, 6.5 Creedmoor, and 7mm Remington Magnum.
What bullet weights have published IMR 4350 data?
Published data covers a wide range of bullet weights depending on the cartridge, such as 120 grain bullets for the 6.5 Creedmoor and 150 to 180 grain bullets for the .30-06 Springfield.
Does Hodgdon publish IMR 4350 data?
Yes, Hodgdon operates the primary online data center for all IMR powders, providing extensive pressure tested load recipes.
Does IMR publish load data for IMR 4350?
IMR powder data is currently managed and published by Hodgdon, which owns the distribution rights to the IMR powder brand.
Why does IMR 4350 load data vary between cartridges?
Every cartridge has a completely different internal case volume and bore diameter, which changes how the burning powder expands and generates pressure.
Does barrel length affect IMR 4350 velocity?
Yes, shorter barrels provide less time for the powder gases to accelerate the bullet, resulting in lower velocities compared to longer laboratory test barrels.
Can IMR 4350 data be used with different bullets?
No, data is specific to the exact bullet brand and profile tested, as variations in bearing surface and jacket material directly affect chamber pressure.
What is the difference between starting and maximum IMR 4350 load data?
The starting load is the lowest recommended charge for safe ignition and baseline pressure, while the maximum load is the absolute highest charge tested before exceeding safety limits.
Where can I find pressure-tested IMR 4350 data?
Pressure tested data is strictly found in the official loading manuals published by ammunition and component manufacturers, which use laboratory equipment to measure exact PSI or CUP.