Test barrel length: 24 in Source: Federal [1] SAAMI [2]
The 7mm Backcountry is a modern rifle cartridge developed to utilize a one piece steel alloy cartridge case patented as Peak Alloy case technology, which is able to withstand higher pressures than traditional brass alloys. Accirding to Fedrak this case technology was developed in response to U.S. military solicitations.[3] The objective is to obtain higher muzzle velocities from short-barreled rifles, which are lighter and easier to carry than the long rifles traditionally used for shooting at extended range.[4] The cartridge is dimensionally similar to the .30-06 Springfield and its derivatives, particularly the .280 Remington and .280 Ackley Improved. Federal Premium Ammunition designed the cartridge to utilize long, heavy-for-caliber bullets due to their superior ballistic coefficients.[5]
Bolt thrust generated by a standard, .473 in (12.0 mm) diameter case head operating at 80,000psi (551.6MPa)[6] is equivalent to a .532 in (13.51 mm) case head operating at 64,000psi (441.3MPa). Accordingly, any rifle action compatible with existing magnum cartridges, such as the .300 PRC, is also compatible with the 7mm Backcountry. Additionally, due to differences in the mechanics of shear transfer, the steel case of the 7mm Backcountry imparts less bolt thrust than an equivalent high-pressure brass case.[7]
Performance
Federal claims that the 7mm Backcountry is "the fastest 7mm [cartridge] on the market."[8] Early reports indicate that it approximates the performance of a 24-inch 7mm Remington Magnum with a 16-inch barrel.[9]
According to early coverage by outdoor writer John Snow, the 7mm Backcountry uses propellant(s) presently unavailable for handloading,[13] though Federal has now published load data using Alliant, Hodgdon, Ramshot, and Vihtavuorismokeless powders.[14] These loads match the velocity claims of Federal’s factory ammunition when figures from equivalent barrel lengths are compared, and Federal describes the data as "...high-pressure loads for Peak Alloy cases only."[8][14]
To guard against corrosion, Federal does not recommend reloading cases with a zinc-nickel-plated exterior; for this purpose, nickel-plated cases are preferred.[15] Trimming, deburring, and some cleaning procedures commonly used in handloading brass cases may damage the nickel-plated steel case; and wax lubricants are recommended to minimize resizing effort. Lightly flaring the case mouth is advisable to avoid damaging the bullet during seating.[16]
Suppressors
The 7mm Backcountry produces relatively intense muzzle blast from short barrels, which encourages the use of suppressors. According to Federal engineers, "...despite the high pressures the round develops in the chamber, the pressure at the muzzle is no greater than a regular 7mm magnum round, like the 7mm PRC."[13] Accordingly, where laws permit, the same suppressors may be used.
The chambering was up to 2026 not registered and hence certified by the C.I.P. that rules arms and ammunition safety in its (mainly European) member states, obstructing commercial acceptance in these countries. Until the 7mm Backcountry is officially certified by the C.I.P. standardization organization, it remains a wildcat cartridge in these countries.[17]
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