7mm Backcountry
| 7mm Backcountry | |
|---|---|
| Type | Rifle |
| Place of origin | United States |
| Production history | |
| Designed | 2024 |
| Manufacturer | Federal Premium Ammunition |
| Specifications | |
| Case type | Rimless, bottleneck |
| Bullet diameter | .284 in (7.224 mm) |
| Neck diameter | .317 in (8.05 mm) |
| Shoulder diameter | .4585 in (11.646 mm) |
| Base diameter | .4698 in (11.93 mm) |
| Rim diameter | .472 in (11.99 mm) |
| Rim thickness | .049 in (1.24 mm) |
| Case length | 2.417 in (61.39 mm) |
| Overall length | 3.34 in (84.84 mm) |
| Rifling twist | 1 in 8 in (203.2 mm) |
The 7mm Backcountry is a modern rifle cartridge using cartridge cases of a proprietary steel alloy able to withstand higher pressures than traditional brass alloys. The objective is to obtain higher muzzle velocities from short-barreled rifles which are lighter and easier to carry than 20th-century rifles intended for long range shooting.[1] The cartridge was introduced by Federal Premium Ammunition loaded with long, heavy bullets for superior ballistic coefficients.[2]
Although the rimless cartridge uses the same .472 in (12.0 mm) diameter as early 20th-century military cartridges widely used as a basis for civilian hunting ammunition, the pressure increase to 80,000 psi (550,000 kPa) from the long-established SAAMI limit of 65,000 psi (450,000 kPa) may make the cartridge unsuitable for 20th-century firearm actions like the Gewehr 98, M1903 Springfield, and contemporary civilian models.[1] The cartridge uses a propellant presently unavailable for handloading and available smokeless powders may not be designed for that pressure. Resizing the fired steel case may be difficult with traditional handloading equipment. The high design pressure produces relatively intense muzzle blast from short barrels encouraging use of suppressors which are heavily regulated in some jurisdictions.[3]
See also
[edit]References
[edit]- ^ a b Mann, Richard A. (January 7, 2025). "Federal's 7mm Backcountry: Life At 80,000 PSI". Gun Digest. Archived from the original on January 15, 2025. Retrieved 2 February 2025.
- ^ Zent, John (2025). "A Case for Strength". American Rifleman. 173 (2). National Rifle Association of America: 36–41.
- ^ Snow, John B. (January 7, 2025). "Federal 7mm Backcountry, Tested and Reviewed". Outdoor Life. Archived from the original on January 7, 2025. Retrieved 2 February 2025.