Reliable 300 Blackout load data can be found directly from established component manufacturers, including Hodgdon, Hornady, Sierra, Vihtavuori, and Western Powders. Published load data normally includes bullet type, cartridge overall length (COAL), powder, starting charge, maximum charge, muzzle velocity, pressure, and test barrel length.Common bullet weights covered by available data range from lightweight 110-grain supersonic projectiles up to heavy 220-grain subsonic projectiles.Data varies between manufacturers and component combinations because laboratory testing uses distinct test barrels, primers, brass cases, and seating depths, all of which alter internal chamber pressure and gas volume.
300 Blackout Load Data
| Bullet | Bullet Weight | Powder | Published Starting Load | Published Maximum Load | Published Max Velocity | Barrel Length | Source |
| Hornady V-MAX | 110 gr | Hodgdon H110 | 18.8 gr | 20.0 gr | 2,382 fps | 16″ | Hodgdon |
| Hornady V-MAX | 110 gr | Hodgdon Lil’Gun | 18.9 gr | 20.0 gr | 2,388 fps | 16″ | Hodgdon |
| Nosler Ballistic Tip | 125 gr | Hodgdon H110 | 16.7 gr | 17.8 gr | 2,118 fps | 16″ | Hodgdon |
| Nosler Ballistic Tip | 125 gr | Hodgdon Lil’Gun | 16.9 gr | 18.0 gr | 2,185 fps | 16″ | Hodgdon |
| Sierra TMK | 125 gr | Winchester 296 | 18.2 gr | 20.5 gr | 2,200 fps | 16″ | Sierra |
| Hornady Sub-X | 190 gr | Hodgdon CFE BLK | 11.8 gr | 12.5 gr | 1,050 fps | 16″ | Hornady |
| Sierra HPBT | 220 gr | Hodgdon CFE BLK | 11.5 gr | 12.1 gr | 1,080 fps | 16″ | Hodgdon |
| Sierra HPBT | 220 gr | Accurate 1680 | 10.7 gr | 11.5 gr | 1,060 fps | 16″ | Accurate |
| Hornady V-MAX | 110 gr | Vihtavuori N110 | 14.8 gr | 16.8 gr | 2,313 fps | 16″ | Vihtavuori |
| Lapua B408 | 200 gr | Vihtavuori N120 | 10.5 gr | 11.8 gr | 1,080 fps | 16″ | Vihtavuori |
Understanding The 300 Blackout Load Data
Reading a 300 blackout load data chart requires understanding how ballistics laboratory test parameters map to handloading metrics.
- Starting load: The minimum published powder charge. In supersonic loads, this ensures safe starting pressures. In subsonic loads, starting loads are calibrated to ensure the bullet exits the barrel without creating a bore obstruction (squib).
- Maximum published load: The maximum safe powder charge tested by a laboratory that remains at or below the SAAMI maximum average pressure (MAP) limit of 55,000 PSI for 300 AAC Blackout.
- Velocity: The speed of the projectile at the muzzle measured in feet per second (fps) using a specific test barrel length.
- Pressure:The peak internal chamber pressure generated during ignition, reported in pounds per square inch (PSI) or copper units of pressure (CUP).
- Bullet weight: The mass of the projectile in grains. 300 BLK data spans two distinct operational profiles: lightweight supersonic (110–135 gr) and heavy subsonic (190–220 gr).
- Powder: The specific propellant type. 300 BLK requires fast-burning rifle or magnum pistol powders to generate appropriate gas volume within short case dimensions.
- Barrel length: The length of the test barrel (typically 16 inches for standard SAAMI laboratory testing).
- Test conditions:Controlled laboratory environment parameters including specific primer brands, case makes, and cartridge overall length (COAL).
Two reputable sources frequently publish different starting and maximum loads for similar bullet weights. For example, Sierra and Hodgdon list different powder charges for 125-grain projectiles because they utilize different internal case capacities, different primer heat outputs, and different bullet bearing surface lengths, which alter friction and pressure curves.
300 Blackout Bullet Weight Load Data
Because the 300 AAC Blackout was designed to function in both supersonic and suppressed subsonic roles, published 300 blackout bullet weights cover a broad spectrum.
- 110 grain: The benchmark weight for high-velocity supersonic performance. Hornady V-MAX and Barnes TAC-TX bullets loaded with powders like H110 or Lil’Gun achieve 2,300 to 2,400 fps out of a 16-inch barrel, offering flat trajectories for hunting and defense.
- 120 grain & 125 grain:Highly versatile supersonic weights.Sierra TMK, Speer TNT, and Nosler Ballistic Tip projectiles deliver velocities around 2,100 to 2,250 fps. They balance high terminal expansion with manageable chamber pressures.
- 135 grain & 150 grain:Mid-weight supersonic options.While 150-grain bullets (such as standard .308 FMJ) are inexpensive, their longer bearing surface reduces available powder volume inside the 300 BLK case, resulting in lower velocities (~1,900 fps).
- 168 grain & 180 grain: Transition weights rarely used in semi-automatic AR-15 platforms. They are often too slow for reliable supersonic expansion and too fast for quiet subsonic performance without custom tuning.
- 190 grain: Engineered specifically for subsonic expanders, such as the Hornady Sub-X. Published data yields around 1,000 to 1,050 fps, preserving energy while remaining under the speed of sound.
- 200 grain, 208 grain & 220 grain:The standard for subsonic 300 blackout load data.Heavy projectiles like the Sierra MatchKing 220 gr HPBT or Hornady 208 gr ELD-M maximize momentum and energy transfer when fired through sound suppressors at velocities between 1,000 and 1,080 fps.
300 Blackout Powder Load Data
Selecting the correct 300 blackout powder is critical due to the cartridge’s small case capacity and gas-system cycling demands in semi-automatic firearms.
| Powder | Bullet | Bullet Weight | Published Starting Load | Published Maximum Load | Published Max Velocity | Source |
| Hodgdon H110 | Hornady V-MAX | 110 gr | 18.8 gr | 20.0 gr | 2,382 fps | Hodgdon |
| Hodgdon Lil’Gun | Nosler Ballistic Tip | 125 gr | 16.9 gr | 18.0 gr | 2,185 fps | Hodgdon |
| Hodgdon CFE BLK | Sierra HPBT | 220 gr | 11.5 gr | 12.1 gr | 1,080 fps | Hodgdon |
| Accurate 1680 | Sierra HPBT | 220 gr | 10.7 gr | 11.5 gr | 1,060 fps | Accurate |
| Winchester 296 | Sierra TMK | 125 gr | 18.2 gr | 20.5 gr | 2,200 fps | Sierra |
| Vihtavuori N110 | Hornady V-MAX | 110 gr | 14.8 gr | 16.8 gr | 2,313 fps | Vihtavuori |
| Vihtavuori N120 | Lapua B408 | 200 gr | 10.5 gr | 11.8 gr | 1,080 fps | Vihtavuori |
| IMR 4227 | Hornady V-MAX | 110 gr | 17.6 gr | 19.5 gr | 2,130 fps | Hodgdon |
Load recipes published for a specific bullet weight cannot be freely transferred to a different bullet profile without adjusting for bearing surface and case volume.
300 Blackout Bullet And Powder Combinations
During 300 blackout load development, component selection directly impacts cycle reliability and safety.
- Bullet construction and bearing surface: Monolithic copper bullets (such as the Barnes TAC-TX) are longer than lead-core bullets of the same weight. Their longer body occupies more internal case space, raising pressure if seated to the same overall length.
- Seating depth and COAL:Maximum cartridge overall length for the 300 BLK is 2.260 inches to fit standard AR-15 STANAG magazines. Seating long subsonic bullets deeper reduces internal powder capacity dramatically, altering the pressure curve.
- Gas system cycling:Semiautomatic AR-15 rifles require sufficient gas pressure at the gas port to cycle the action.Powders like Hodgdon CFE BLK and Accurate 1680 generate high gas volume at lower pressures, making them ideal for cycling subsonic 220-grain loads.
- Brass source: Converted .223/5.56 brass often has thicker neck walls than commercial 300 BLK brass. Using converted brass with thick necks can cause bullet pinch in the chamber, leading to dangerous over-pressure conditions.
- Primers:Most published data specifies standard Small Rifle Primers (e.g., CCI 400, Winchester WSR) or Small Rifle Magnum primers to ensure clean ignition of dense powder charges.
300 Blackout Velocity From Published Data
Published 300 blackout velocity specifications vary significantly between supersonic and subsonic configurations.
- 110 gr Hornady V-MAX | Hodgdon H110 | 20.0 gr Max | 2,382 fps(16″ Barrel, Hodgdon)
- 125 gr Nosler BT | Hodgdon Lil’Gun | 18.0 gr Max | 2,185 fps(16″ Barrel, Hodgdon)
- 190 gr Hornady Sub-X | Hodgdon CFE BLK | 12.5 gr Max | 1,050 fps (16″ Barrel, Hornady)
- 220 gr Sierra HPBT | Accurate 1680 | 11.5 gr Max | 1,060 fps (16″ Barrel, Accurate)
Manufacturer-published velocities represent measurements taken from un-ported universal test barrels. Independent chronograph tests from consumer rifles usually show slightly lower velocities due to gas bleed through the gas block and shorter barrel lengths. Ballistic calculator estimates provide mathematical trajectories but do not measure actual physical output.
300 Blackout Load Data By Barrel Length
Barrel length significantly alters velocity for supersonic 300 BLK rounds, whereas subsonic loads are purposefully throttled to stay below the sound barrier regardless of barrel length.
Standard published 300 blackout reloading data utilizes a 16-inch test barrel as the baseline.However, the cartridge is frequently fired out of short-barreled rifles (SBRs) and AR pistols with 8.5-inch, 9-inch, or 10.5-inch barrels.
- 16-inch Barrel:Achieves complete powder burn for supersonic loads, yielding top published velocities (2,350–2,400 fps with 110 gr bullets).
- 10.5-inch Barrel: Loses approximately 150 to 200 fps with supersonic loads (~2,180 fps with 110 gr bullets), but retains full gas port pressure for cycling.
- 8.5-inch Barrel: Loses roughly 250 to 300 fps with supersonic loads (~2,080 fps with 110 gr bullets). Subsonic loads fired through short barrels require bulkier, gas-generating powders like CFE BLK to reliably cycle the bolt without a suppressor attached.
300 Blackout Energy And Ballistics
The ballistic performance of 300 BLK depends entirely on whether supersonic or subsonic ammunition is used.
110-grain Supersonic (Muzzle Velocity: 2,380 fps, 16″ Barrel):
- Muzzle Energy: ~1,380 ft-lbs
- 100-yard Velocity: ~2,094 fps
- 200-yard Velocity:~1,834 fps
- Energy at 100 yards: ~1,071 ft-lbs
220-grain Subsonic (Muzzle Velocity: 1,050 fps, 16″ Barrel):
- Muzzle Energy: ~538 ft-lbs
- 100-yard Velocity: ~980 fps
- 200-yard Velocity: ~930 fps
- Energy at 100 yards: ~470 ft-lbs
While supersonic loads carry superior trajectory and energy for mid-range hunting, subsonic loads preserve their momentum over distance due to low drag, making them quiet and effective for close-range applications.
Manufacturer Data vs Independent Testing
When analyzing 300 blackout reload data, differentiate between laboratory testing and consumer reports:
- Manufacturer-published data:Derived using SAAMI-standard pressure barrels equipped with piezoelectric sensors. This confirms that a specific 300 blackout powder charge stays within the 55,000 PSI limit.
- Independent chronograph tests: Conducted by shooters using personal firearms. While helpful for checking actual velocity in SBR configurations, chronographs cannot measure internal chamber pressure.
- User-submitted load reports: Online forum recipes often lack pressure verification. Relying on user recipes risks severe over-pressure, brass failure, or weapon damage.
Always prioritize pressure-tested manufacturer data from Hodgdon, Hornady, Sierra, or Vihtavuori over unverified user reports.
300 Blackout Pressure And Safety
The SAAMI maximum pressure limit for the 300 AAC Blackout is 55,000 PSI. Handloaders must follow safety protocols to prevent catastrophic over-pressure.
- Subsonic Squib Hazard: Unlike supersonic cartridges where over-charging is the primary danger, subsonic 300 blackout load development carries the risk of under-charging. If a powder charge is reduced too far, the bullet may fail to exit the barrel, creating a squib load that will destroy the barrel if a secondary shot is fired.
- Powder Substitution Dangers: Slow rifle powders (like Varget or H4895) will not cycle in 300 BLK, while fast pistol powders (like Bullseye or Titegroup) can cause extreme pressure spikes at minimal charge weights.
- Converted Brass Neck Thickness: Forming 300 BLK cases from converted 5.56 NATO brass requires measuring neck thickness. Extra-thick case necks can clamp down on the bullet inside the chamber, causing pressure spikes well above 55,000 PSI.
- Temperature Sensitivity: Double-base powders like Lil’Gun can run hot under rapid-fire conditions, altering pressure and velocity curves.
Best Sources For 300 Blackout Load Data
The primary, pressure-tested sources for 300 blackout load data include:
- Hodgdon Reloading Data Center: Provides comprehensive, free online data for Hodgdon, IMR, Winchester, and Accurate powders, covering both supersonic and subsonic bullet weights.
- Hornady Handbook of Cartridge Reloading: The definitive source for 300 blackout load data Hornady, including detailed metrics for V-MAX, CX, and Sub-X projectiles.
- Sierra Bullets Manual:Excellent data specifically breaking down accuracy and hunting loads for 110-grain through 220-grain MatchKing and GameKing bullets.
- Vihtavuori Reloading Data: Offers pressure-tested recipes for N110, N120, and N320 powders paired with European and American projectiles.
Common 300 Blackout Load Data Questions
Where can I find 300 Blackout load data?
Official 300 blackout reloading data is published online by Hodgdon, Hornady, Sierra, Nosler, and Vihtavuori.
What powders are used in published 300 Blackout data?
Common powders include Hodgdon H110, Lil’Gun, CFE BLK, Winchester 296, Accurate 1680, IMR 4227, and Vihtavuori N110.
What bullet weights have 300 Blackout load data?
Published data covers bullet weights from 110 grains up to 220 grains.
What is the best powder for subsonic 300 Blackout load data?
Hodgdon CFE BLK and Accurate 1680 are the most widely published powders for subsonic loads because they generate sufficient gas volume to cycle AR-15 actions.
Why does 300 Blackout load data vary between sources?
Variations occur due to differences in test barrel dimensions, brass wall thickness, primer choice, powder lot variations, and cartridge overall seating length.
Does barrel length affect 300 Blackout velocity?
Yes. Supersonic 300 BLK loads lose 15 to 30 fps per inch when moving from a 16-inch barrel down to an 8.5-inch or 10.5-inch barrel.
Can the same powder charge be used with a different bullet weight?
No. Changing bullet weight or construction alters internal seating depth and pressure. Always use data specific to the exact bullet weight and profile.
What is the difference between starting and maximum published load data?
The starting load is a safe initial baseline, while the maximum load represents the highest charge tested before hitting the SAAMI pressure ceiling of 55,000 PSI.
Where can I find pressure-tested 300 Blackout data?
The Hodgdon Reloading Data Center and Hornady Reloading Manual provide verified, pressure-tested laboratory data.
Does Hornady publish 300 Blackout load data?
Yes, 300 blackout load data Hornady is available in their reloading handbook and online for bullets ranging from 110 gr to 208 gr.
Does Hodgdon publish 300 Blackout load data?
Yes, 300 blackout load data Hodgdon is maintained on their online database for CFE BLK, H110, Lil’Gun, and IMR powders.
Final Verdict
When developing a 300 blackout load recipe, handloaders should source data exclusively from primary component manufacturers like Hodgdon, Hornady, Sierra, and Vihtavuori.Compare powder charge weights alongside bullet profile, seating depth (COAL), brass wall thickness, and test barrel length.Because 300 BLK performance relies on distinct pressure thresholds for supersonic expansion and subsonic gas-system cycling, adhering strictly to pressure-tested published load data is essential for safety, firearm function, and terminal performance.