Traditional sporting bullets
Flat-nose, round-nose, and soft-point designs remain important in these cartridge families. For tubular magazines, use ammunition specifically approved by the manufacturer.
THE CARTRIDGE LIBRARY · LARGE-BORE CENTERFIRE
.450 Bushmaster
A straight-wall .45-caliber sporting-rifle cartridge. Factory loads use a different case and bullet specification from .458 SOCOM.
2A Ledger reference desk · Sources checked October 18, 2026
Read the dimensions
- Overall · min–max
- 2.000–2.260 in
50.800–57.404 mm - Case length · max
- 1.700 in
43.180 mm - Bullet maximum
- 0.4525 in
11.494 mm - Rim diameter · max
- 0.473 in
12.014 mm
Know the exact name
At a glance
- Cartridge family
- Large-bore centerfire
- Bullet specification
- 0.4525 in / 11.494 mmBullet maximum
- Factory examples
- 6 loadsSelected, sourced examples below
- Weight in cited examples
- 245–395 grGrains measure mass, not powder charge
.450 Bushmaster is identified by its complete cartridge designation. The resource-table alternative is 450 Bushmaster. A caliber number, bullet diameter, or family resemblance on its own does not identify ammunition compatibility.
.450 Bushmaster, .458 SOCOM, .45-70, and .450 Marlin are separate cartridges.
Dimensions: open the exact dimensional drawing ↗. The displayed number is bullet maximum, rather than an assertion that every manufactured projectile or barrel has this exact diameter.
Origins & evolution
Background & development
The .450 Bushmaster reached the market in 2007 through a collaboration involving Tim LeGendre of LeMag Firearms, Bushmaster and Hornady. LeGendre’s earlier .45 Professional was influenced by Jeff Cooper’s idea of a large-bore, self-loading general-purpose hunting rifle, often called the Thumper concept. Bushmaster licensed the design, and Hornady developed the commercial ammunition.
The production cartridge was modified to suit Hornady’s chosen bullet and the intended rifle envelope, and the name became .450 Bushmaster with LeGendre’s agreement. Its original identity was closely tied to a large-bore AR-pattern hunting rifle. Factory support later broadened beyond that initial platform, while straight-wall hunting-cartridge demand gave it another audience. Hornady’s 2019 addition of an American Whitetail loading documents that continuing shift into mainstream deer-hunting ammunition. The history is a sequence of an individual designer’s project, a rifle-company partnership and ammunition-company refinement.
Historical sources: American Rifleman: original big-bore AR evaluation and developer history ↗ · Hornady: 2019 expansion of .450 Bushmaster hunting ammunition ↗
Construction changes the story
Loads, variations & specialty offerings
Purpose-built modern loads
Flexible tips, bonded bullets, monolithic expanding bullets, and solids have different functions. A similar exterior shape or shared diameter does not establish equivalent behavior.
Firearm-specific ammunition
Some older cartridge families span firearms with very different operating limits. Keep any product restrictions with the ammunition record and use only loads authorized for that firearm.
In the cited .450 Bushmaster examples, bullet weights are 245, 250, 260, 300, 395 grains. These are the weights actually present in this source selection, not a claim that every possible loading is listed.
Bullet construction background: Hornady: anatomy of a bullet ↗. Exact product descriptions and velocities are cited in the factory table.
From the factory catalog
245 grains
2,200 fps
InterLock® (20" Bbl)
250 grains
2,200 fps
FTX® (20" Bbl)
260 grains
2,200 fps
FUSION
Compare all 6 cited factory load records
| Maker / product | Bullet mass | Published construction | Muzzle velocity | Test barrel | Source |
|---|---|---|---|---|---|
| Hornady82242 | 245 gr 15.88 g | InterLock® (20" Bbl) | 2,200 fps 671 m/s | 20 in | Hornady · PDF p. 188 ↗ |
| Hornady82244 | 250 gr 16.20 g | FTX® (20" Bbl) | 2,200 fps 671 m/s | 20 in | Hornady · PDF p. 189 ↗ |
| Hornady82246 | 250 gr 16.20 g | FTX® (20" Bbl) | 2,200 fps 671 m/s | 20 in | Hornady · PDF p. 189 ↗ |
| FederalF450BMFS1 | 260 gr 16.85 g | FUSION | 2,200 fps 671 m/s | 24 in | Federal · PDF pp. 58–59 ↗ |
| Federal450BMB | 300 gr 19.44 g | SP | 1,900 fps 579 m/s | 24 in | Federal · PDF pp. 56–57 ↗ |
| Hornady82247 | 395 gr 25.60 g | SUB-X™ (20" Bbl) | 1,050 fps 320 m/s | 20 in | Hornady · PDF p. 189 ↗ |
Explore the published data
Ballistics you can inspect
Select a legend entry to add or remove its line. Hover or tap a plotted point, or use the position slider. With the graph focused, arrow keys move the inspector. Solid dots identify source points; dashed connectors show estimates between them. Load construction, pressure category, and test setup can differ even at the same grain weight.
Read the original values as accessible tables
.450 Bushmaster: factory velocity downrange
| Exact load | Source | Published points |
|---|---|---|
| 245 gr Hornady InterLock® (20" Bbl) | Hornady | 0: 2200; 100: 1742; 200: 1364; 300: 1103 |
| 250 gr Hornady FTX® (20" Bbl) | Hornady | 0: 2200; 100: 1835; 200: 1515; 300: 1255 |
| 260 gr Federal FUSION | Federal | 0: 2200; 100: 1777; 200: 1419; 300: 1155; 400: 1002; 500: 907 |
| 300 gr Federal SP | Federal | 0: 1900; 100: 1602; 200: 1346; 300: 1153; 400: 1028; 500: 945 |
| 395 gr Hornady SUB-X™ (20" Bbl) | Hornady | 0: 1050; 100: 977; 200: 921; 300: 874 |
| 250 gr Hornady FTX® (20" Bbl) | Hornady | 0: 2200; 100: 1835; 200: 1515; 300: 1255 |
How to interpret the comparison
Changing bullet weight also often changes bullet design and propellant choice. Two curves are comparisons of the listed products, not a controlled experiment proving that bullet weight alone caused the difference. Catalog downrange points are projections under the maker’s conditions; barrel-study points are recorded observations in the study firearm.
Direct answers
Common questions
What is .450 Bushmaster?
A straight-wall .45-caliber sporting-rifle cartridge. Factory loads use a different case and bullet specification from .458 SOCOM.
What diameter does .450 Bushmaster use?
The cited dimensional standard lists 0.4525 inches (11.494 mm), bullet maximum. This drawing convention is different from a casual caliber nickname.
Are similarly named cartridges interchangeable?
.450 Bushmaster, .458 SOCOM, .45-70, and .450 Marlin are separate cartridges.
Are the graph values measured or estimated?
The downrange view uses the exact manufacturer catalog records shown in the source table. Dashed connectors and intermediate inspector values use linear interpolation between the displayed source points. Calculated energy uses the listed bullet mass and velocity.
Does higher energy mean the best load?
Energy is calculated from mass and velocity. It does not establish accuracy, expansion, penetration, pattern density, recoil, or suitability for a particular firearm. Use the exact product documentation and firearm manual.
Trace the facts
Sources & methodology
Compiled by 2A Ledger from the linked standards, manufacturer publications, and identified test records. Checked October 18, 2026. Historical tests and older catalogs retain their original dates; a listing here does not establish current availability.
- SAAMI: dimensional drawing · PDF p. 169 ↗
- Hornady · PDF p. 188 ↗
- Hornady · PDF p. 189 ↗
- Federal · PDF pp. 58–59 ↗
- Federal · PDF pp. 56–57 ↗
- American Rifleman: original big-bore AR evaluation and developer history ↗
- Hornady: 2019 expansion of .450 Bushmaster hunting ammunition ↗
Diameter figures preserve the cited drawing convention. Inch–millimeter conversion uses exactly 25.4 mm per inch. Factory specifications describe the maker’s test setup; your firearm, ammunition lot, temperature, and measuring method can produce different results. This is an educational factory-ammunition reference, not a reloading manual.