Practice & target
Full-metal-jacket, plated, lead, and wadcutter bullets describe different constructions. Grain weight is projectile mass; it does not state a powder charge or guarantee recoil.
THE CARTRIDGE LIBRARY · REVOLVER & LEVER-ACTION RIFLE
.327 Federal Magnum
A rimmed .32-family magnum revolver cartridge with a longer case and a distinct pressure specification from .32 H&R Magnum.
2A Ledger reference desk · Sources checked October 18, 2026
Read the dimensions
- Overall · min–max
- 1.275–1.475 in
32.385–37.465 mm - Case length · max
- 1.200 in
30.480 mm - Bullet maximum
- 0.313 in
7.950 mm - Rim diameter · max
- 0.375 in
9.525 mm
Know the exact name
At a glance
- Cartridge family
- Revolver & lever-action rifle
- Bullet specification
- 0.3130 in / 7.950 mmBullet maximum
- Factory examples
- 6 loadsSelected, sourced examples below
- Weight in cited examples
- 80–104 grGrains measure mass, not powder charge
.327 Federal Magnum is identified by its complete cartridge designation. The resource-table alternative is 327 Fed Mag. A caliber number, bullet diameter, or family resemblance on its own does not identify ammunition compatibility.
The .327 Federal Magnum, .32 H&R Magnum, and .32 S&W Long retain separate cartridge specifications. Follow the firearm manufacturer’s listed ammunition.
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
Federal and Ruger introduced the .327 Federal Magnum in 2007. Ruger’s November announcement paired it with a six-shot SP101, emphasizing the ability to offer six cartridges in a compact revolver size often associated with five-shot .357 Magnum models. The cartridge extended the rimmed .32-caliber family beyond the earlier .32 H&R Magnum.
The initial idea was therefore not simply a smaller bullet in a powerful revolver. It combined a compact firearm, additional cylinder capacity and a higher-performance .32 cartridge. Ruger subsequently announced .327-chambered GP100 and Blackhawk models in 2010, widening the available platforms. Its later use in lever-action rifles gives it a second sporting context beyond the original compact-handgun launch. The Federal name identifies the ammunition-company partnership, while Ruger’s contemporary announcements show how closely the cartridge’s introduction was tied to particular firearm designs and their capacity.
Historical sources: Ruger: original .327 Federal Magnum SP101 announcement ↗ · Ruger: 2010 .327 GP100 and Blackhawk announcement ↗ · Henry: Big Boy manual listing .327 Federal Magnum rifle chambering ↗
Construction changes the story
Loads, variations & specialty offerings
Expanding factory bullets
JHP, XTP, FTX, HST, and similar product names refer to particular designs. Muzzle energy alone does not show expansion, penetration, or reliability in a particular firearm.
Specialty load families
Reduced-recoil, subsonic, monolithic, and heavier-bullet offerings are product-specific. A +P marking is a pressure category where standardized, not simply a heavier bullet. Follow the maker’s exact product and firearm guidance.
In the cited .327 Federal Magnum examples, bullet weights are 80, 85, 100, 104 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
80 grains
1,475 fps
FTX ®
85 grains
1,400 fps
JSP
100 grains
1,500 fps
JSP
Compare all 6 cited factory load records
| Maker / product | Bullet mass | Published construction | Muzzle velocity | Test barrel | Source |
|---|---|---|---|---|---|
| Hornady90061 | 80 gr 5.18 g | FTX ® | 1,475 fps 450 m/s | 5 in | Hornady · PDF p. 191 ↗ |
| FederalAE327A | 85 gr 5.51 g | JSP | 1,400 fps 427 m/s | 4-V in | Federal · PDF p. 61 ↗ |
| FederalPD327HS1 | 85 gr 5.51 g | HYDRA-SHOK | 1,400 fps 427 m/s | 4-V in | Federal · PDF p. 60 ↗ |
| FederalAE327 | 100 gr 6.48 g | JSP | 1,500 fps 457 m/s | 4-V in | Federal · PDF p. 61 ↗ |
| FederalP327SA | 100 gr 6.48 g | SWIFT A-FRAME | 1,500 fps 457 m/s | 4-V in | Federal · PDF p. 60 ↗ |
| FederalP327HST1S | 104 gr 6.74 g | HST | 1,525 fps 465 m/s | 4 in | Federal · PDF p. 60 ↗ |
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
.327 Federal Magnum: velocity by barrel length
| Exact load | Source | Published points |
|---|---|---|
| Federal 85 gr. Hydra-Shok | BBTI | 2: 976; 3: 1331; 4: 1462; 5: 1581; 6: 1675; 8: 1752; 10: 1803; 12: 1838; 14: 1869; 16: 1900; 18: 1910 |
| American Eagle 100 gr. JSP | BBTI | 2: 1056; 3: 1398; 4: 1604; 5: 1701; 6: 1808; 7: 1874; 8: 1913; 9: 1957; 10: 1950; 11: 2023; 12: 2063; 13: 2072; 14: 2112; 15: 2128; 16: 2141; 17: 2158; 18: 2186 |
| Speer 115 gr. Gold Dot | BBTI | 2: 1042; 3: 1316; 4: 1451; 5: 1535; 6: 1639; 7: 1659; 8: 1681; 9: 1727; 10: 1738; 11: 1773; 12: 1785; 13: 1815; 14: 1816; 15: 1875; 16: 1894; 17: 1848; 18: 1880 |
.327 Federal Magnum: factory velocity downrange
| Exact load | Source | Published points |
|---|---|---|
| 80 gr Hornady FTX ® | Hornady | 0: 1475; 50: 1275; 100: 1124 |
| 85 gr Federal JSP | Federal | 0: 1400; 25: 1306; 50: 1221; 75: 1150; 100: 1091 |
| 100 gr Federal JSP | Federal | 0: 1500; 25: 1408; 50: 1324; 75: 1248; 100: 1181 |
| 104 gr Federal HST | Federal | 0: 1525; 25: 1080; 50: 895; 75: 781; 100: 690 |
| 85 gr Federal HYDRA-SHOK | Federal | 0: 1400; 25: 1306; 50: 1221; 75: 1150; 100: 1091 |
| 100 gr Federal SWIFT A-FRAME | Federal | 0: 1500; 25: 1411; 50: 1329; 75: 1254; 100: 1189 |
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 .327 Federal Magnum?
A rimmed .32-family magnum revolver cartridge with a longer case and a distinct pressure specification from .32 H&R Magnum.
What diameter does .327 Federal Magnum use?
The cited dimensional standard lists 0.3130 inches (7.950 mm), bullet maximum. This drawing convention is different from a casual caliber nickname.
Are similarly named cartridges interchangeable?
The .327 Federal Magnum, .32 H&R Magnum, and .32 S&W Long retain separate cartridge specifications. Follow the firearm manufacturer’s listed ammunition.
Are the graph values measured or estimated?
BBTI points come from the cited cut-down barrel study. 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
Skives & petals: read the jacket construction →
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. 44 ↗
- Ruger: .327 Federal revolver and factory-load announcement ↗
- Hornady · PDF p. 191 ↗
- Federal · PDF p. 61 ↗
- Federal · PDF p. 60 ↗
- Ballistics by the Inch: archived measured barrel data (2020 archive) ↗
- BBTI: study index and source records ↗
- Ruger: original .327 Federal Magnum SP101 announcement ↗
- Henry: Big Boy manual listing .327 Federal Magnum rifle chambering ↗
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.