450 Bushmaster Load Data

Reliable 450 Bushmaster load data can be found in official reloading manuals from Hornady, Barnes, and Hodgdon’s online Reloading Data Center. Published load data for this straight-walled cartridge typically includes specific powder charges, primer types (usually small rifle or small rifle magnum), overall cartridge lengths (max 2.260″), and velocities shot from 16-inch to 24-inch test barrels. Available 450 Bushmaster bullet weights cover a wide spectrum of .452-inch projectiles, commonly ranging from 200-grain all-copper bullets to heavy 300-grain jacketed hollow points. Powder manufacturers like Hodgdon predominantly publish data utilizing fast-burning magnum pistol powders like H110 and Lil’Gun. It is critical to follow published 450 Bushmaster reload data exactly, because data can vary significantly between sources due to differences in bullet bearing surface, seating depth, and the cartridge’s strict SAAMI pressure limits.

450 Bushmaster Load Data

BulletBullet WeightPowderPublished Starting LoadPublished Maximum LoadPublished VelocityBarrel LengthSource
Hornady FTX250 grainHodgdon H11033.0 gr39.2 gr2,200 fps20″Hornady / Hodgdon
Barnes XPB200 grainHodgdon Lil’Gun38.0 gr42.5 gr2,600 fps24″Barnes
Hornady XTP Mag300 grainIMR 419840.0 gr42.8 gr1,940 fps20″Hodgdon
Barnes TSX275 grainHodgdon H11031.0 gr34.5 gr1,920 fps20″Barnes
Hornady FTX225 grainHodgdon Lil’Gun36.0 gr40.5 gr2,350 fps20″Hodgdon

Understanding The 450 Bushmaster Load Data

When reading a published 450 Bushmaster load data chart, multiple data points work together to provide a safe reloading baseline for this high-thumper cartridge.

  • Starting load: The minimum powder charge recommended by the publisher. This provides a safe baseline to begin testing without risking squib loads or sudden pressure spikes.
  • Maximum published load: The absolute highest powder charge the publisher tested before encountering pressure signs or reaching the SAAMI maximum average pressure.
  • Velocity: The speed of the bullet as it leaves the muzzle, measured in feet per second (fps).
  • Pressure:The 450 Bushmaster has a SAAMI Maximum Average Pressure (MAP) of 38,500 PSI.
  • Bullet weight: The mass of the projectile in grains.
  • Powder: The specific chemical propellant used. Powders for this cartridge cannot be safely interchanged.
  • Barrel length: The length of the test barrel dictates the velocity. A longer barrel gives the fast-burning powder more time to push the projectile, resulting in higher velocities.
  • Test conditions: Altitude, temperature, and atmospheric pressure all affect ballistics and are sometimes noted in comprehensive manuals.

Published values differ between manufacturers because every company uses slightly different test parameters. Variations in exact barrel bore dimensions, seating depth for AR-15 magazines, and specific powder lots will yield different pressures and velocities.

See also  17 WSM Trajectory Chart

450 Bushmaster Bullet Weight Load Data

The 450 Bushmaster was specifically designed to utilize .452-inch diameter bullets (the same diameter used by the .45 Colt and .454 Casull), heavily modified to withstand high rifle velocities.

  • 200 grain: Supported by bullets like the Barnes XPB. These lightweight, all-copper bullets are designed for high-velocity (often exceeding 2,500 fps) and explosive terminal performance with minimal recoil.
  • 225 grain: Common in legacy quarter-bore cartridge designs, the 225-grain Hornady FTX offers a middle ground for deer hunting, combining flat trajectories with strong terminal performance.
  • 240 to 250 grain: The 250-grain Hornady FTX is the gold standard for the cartridge. It is the bullet utilized in Hornady BLACK factory ammunition and dominates 450 Bushmaster load data.
  • 275 grain:Solid monolithic copper bullets, such as the Barnes TSX, provide maximum penetration on large game like elk or moose without disintegrating upon bone impact.
  • 300 grain: Heavy bullets like the Hornady XTP Mag or Speer DeepCurl offer deep penetration and massive energy transfer, though their trajectories drop significantly past 150 yards.

450 Bushmaster Powder Load Data

Selecting the correct 450 Bushmaster powder is vital. Because it is a straight-walled cartridge with a large bore, it requires fast-burning magnum pistol powders rather than traditional rifle powders.

PowderBulletBullet WeightPublished Starting LoadPublished Maximum LoadPublished VelocitySource
Hodgdon H110Hornady FTX250 grain33.0 gr39.2 gr2,200 fpsHodgdon
Hodgdon Lil’GunBarnes XPB200 grain38.0 gr42.5 gr2,600 fpsBarnes
IMR 4198Hornady XTP Mag300 grain40.0 gr42.8 gr1,940 fpsHodgdon
Accurate No. 9Hornady FTX250 grain29.0 gr34.0 gr2,050 fpsAccurate / Western Powders

Do not assume that a 450 Bushmaster powder charge deemed safe for a 250-grain FTX can automatically be applied to a 250-grain monolithic copper bullet. Monolithic bullets create more friction and seat deeper, significantly raising pressure.

450 Bushmaster Bullet And Powder Combinations

The exact combination of components in your 450 Bushmaster load recipe dictates both safety and accuracy.

  • Bullet construction and bearing surface: Monolithic copper bullets (like the Barnes TSX) have different bearing surfaces than traditional lead-core bullets, requiring a reduction in powder charge.
  • Seating depth:Because the cartridge must fit inside an AR-15 magazine (2.260″ max overall length), heavy 300-grain bullets must be seated very deeply. This sharply reduces internal case capacity and drastically spikes chamber pressure.
  • Case capacity: Dedicated 450 Bushmaster brass from different manufacturers (e.g., Starline vs. Hornady) may have slightly different internal volumes.
  • Primer: The cartridge uses a Small Rifle primer. Substituting a standard primer for a magnum primer alters the powder ignition and pressure curve, especially with ball powders like H110.
  • Crimp: Because the 450 Bushmaster headspaces on the case mouth (like a semi-auto pistol cartridge), it requires a taper crimp. A roll crimp will cause the cartridge to drop too deep into the chamber, resulting in light primer strikes and failure to fire.
See also  222 Remington Accuracy Loads

450 Bushmaster Velocity From Published Data

Velocities for the 450 Bushmaster vary heavily based on the exact bullet and powder charge utilized.

  • 200gr Barnes XPB / Lil’Gun: 2,600 fps (Published Data, 24″ barrel)
  • 250gr Hornady FTX / H110: 2,200 fps (Published Data, 20″ barrel)
  • 275gr Barnes TSX / H110: 1,920 fps (Independent Testing, 20″ barrel)
  • 300gr Hornady XTP Mag / IMR 4198: 1,940 fps (Published Data, 20″ barrel)

It is crucial to distinguish between manufacturer-published velocities (shot in controlled pressure barrels) and independent chronograph testing.

450 Bushmaster Load Data By Barrel Length

Barrel length directly impacts 450 Bushmaster velocity.Most published load data utilizes either a 16-inch, 20-inch, or 24-inch test barrel. If you are shooting a 16-inch AR-15 carbine for hunting, your velocities will be noticeably lower than those published in a manual using a 24-inch test barrel. Conversely, if you are using a 22-inch Ruger American bolt-action rifle, you will extract near-maximum velocity from powders like Lil’Gun.

450 Bushmaster Energy And Ballistics

The 450 Bushmaster is celebrated for its massive terminal energy at close-to-medium ranges.

  • Muzzle Energy: At a muzzle velocity of 2,200 fps, the 250-grain FTX delivers approximately 2,686 ft-lbs of muzzle energy.
  • 200-Yard Velocity and Energy: Because .452-inch bullets have poor ballistic coefficients (they are essentially flying ashtrays), they bleed velocity quickly. At 200 yards, the 250-grain FTX drops to roughly 1,515 fps and retains about 1,274 ft-lbs of energy.
  • Effective Range:Due to its rainbow-like trajectory and rapid loss of velocity, the practical hunting limit for the 450 Bushmaster on medium game is 250 to 300 yards.

Manufacturer Data vs Independent Testing

When undertaking 450 Bushmaster load development, reloader safety relies on understanding the source of the data.

  • Manufacturer-published load data: Derived in a laboratory using SAAMI-spec pressure testing equipment. This is the safest, most authoritative data.
  • Independent chronograph testing: Real-world results from publications and forums. Highly useful for tracking accuracy nodes, but lacks laboratory pressure validation.
  • User-submitted load reports: These are anecdotal and should never be used as a primary source for powder charges.

Always give priority to official 450 Bushmaster load data Hornady or Hodgdon provides when beginning a new recipe.

See also  9mm Twist Rate

450 Bushmaster Pressure And Safety

Safety is paramount in 450 Bushmaster load development. The cartridge operates at a relatively low maximum pressure of 38,500 PSI due to the AR-15 bolt thrust limitations.

Because the case uses fast-burning pistol powders, a difference of just 0.5 grains can cause an enormous pressure spike. Never substitute components in published load data. Changing from a 250-grain FTX to a 250-grain Barnes TTSX alters the internal case volume when seated to 2.260″, which requires a completely different powder charge. Always start at the published starting load and watch carefully for pressure signs on the brass and primer.

Best Sources For 450 Bushmaster Load Data

The strongest current sources for 450 Bushmaster load data include:

  • Hodgdon: The Hodgdon Reloading Data Center is the premier online resource for H110, Lil’Gun, and IMR powder recipes.
  • Hornady: As a massive proponent of the cartridge, the Hornady manual offers the most comprehensive lab-tested load data for their FTX and XTP bullet lines.
  • Barnes Bullets: Provides official, pressure-tested PDF data specifically for their monolithic XPB and TSX bullets.

Common 450 Bushmaster Load Data Questions

Where can I find 450 Bushmaster load data?

Reliable data is available in the Hornady reloading manual, Barnes Bullets online PDFs, and the Hodgdon Reloading Data Center.

What powders are used in published 450 Bushmaster data?

Fast-burning magnum pistol powders are universally used, specifically Hodgdon H110, Hodgdon Lil’Gun, IMR 4198, and Accurate No. 9.

What bullet weights have 450 Bushmaster load data?

Published data covers everything from 200-grain copper hollow points up to 300-grain heavy hunting projectiles.

What is the best source for 450 Bushmaster reloading data?

Hodgdon and Hornady are considered the primary authoritative sources due to their extensive pressure-tested manual updates.

Why does 450 Bushmaster load data vary between sources?

Data varies because different test labs use different brass (which changes internal capacity), different primers, and unique barrel lengths.

Does barrel length affect 450 Bushmaster velocity?

Yes. Published data generally uses 16-inch to 24-inch test barrels. Shorter AR-15 barrels will yield lower velocities.

Can the same powder charge be used with a different bullet?

No. Differences in bullet bearing surface, jacket material, and seating depth mean that powder charges must be strictly tailored to the specific bullet.

What is the difference between starting and maximum published load data?

The starting load is the safest tested minimum, while the maximum is the highest powder charge tested before reaching unsafe pressures (38,500 PSI).

Where can I find pressure-tested 450 Bushmaster data?

Directly from manufacturer manuals and websites, including Hornady, Barnes, and powder manufacturers like Hodgdon.

Does Hornady publish 450 Bushmaster load data?

Yes. Hornady provides official load data for their FTX, XTP, and interlock bullet lines.

Does Hodgdon publish 450 Bushmaster load data?

Yes. Hodgdon includes the 450 Bushmaster in their Reloading Data Center for use with their powders, heavily featuring H110 and Lil’Gun.

Final Verdict

Reloaders looking for a reliable 450 Bushmaster load recipe should source their starting points directly from established manufacturers like Hornady, Barnes, and Hodgdon. When comparing charts, always pay close attention to the specific bullet weight, bullet profile, and overall cartridge length, as the cartridge’s AR-15 magazine restrictions and low 38,500 PSI pressure limit mean slight seating depth changes heavily impact chamber pressure. Using precise, component-specific 450 Bushmaster reloading data is the only way to guarantee both semi-automatic reliability and safety during load development.

Leave a Comment