The Sellier & Bellot 8x57 JRS Rimmed Unprimed Brass Cases (SKU V337632) provide reloadable, unprimed cartridge brass designed specifically for handloading break-action hunting firearms. Packaged in quantities of 20 unprimed brass cases per pack, these cases feature factory-annealed necks to maintain consistent neck tension and extend reloading cycle life. Each case is engineered with a rimmed extraction design and standard Boxer Large Rifle primer pockets, accommodating standard decapping and reloading tools. Designed to accept .323-inch (8.2 mm) diameter bullets, this brass provides the foundation for assembling custom hunting loads complying with the 3,300 bar C.I.P. maximum service pressure standard for rimmed break-action platforms.

Key Features

• Factory-Annealed Case Necks: Undergoes thermal stress relief at the neck and shoulder to prolong brass longevity and maintain uniform bullet seating tension over repeated firing cycles.
• Boxer Primer Pockets: Utilises standard Large Rifle Boxer primer pockets, allowing decapping and priming with standard reloading press tooling without requiring Berdan decapping pins.
• Rimmed Extractor Interface: Formed with a pronounced rim specifically engineered for positive extraction in break-action locking systems.
• Controlled Internal Capacity: Manufactured to meet C.I.P. dimensional specifications, supporting standard operating loads such as a 196-grain projectile loaded to factory velocities around 726 m/s (2,380 fps).
• Component Readiness: Supplied as inert, unprimed brass requiring initial full-length resizing, trimming, and chamfering before charging with user-selected propellants and primers.

Product Specifications

• Brand: Sellier & Bellot (S&B)
• Manufacturer SKU: V337632
• Calibre Designation: 8x57 JRS (also designated 8mm Mauser Rimmed / 8x57 IRS)
• Quantity: 20 unprimed cases per pack
• Compatible Bullet Diameter: .323-inch (8.2 mm) "S" bore
• Primer Pocket Type: Large Rifle Boxer
• Case Profile: Rimmed, bottleneck
• Maximum Service Pressure (C.I.P.): 3,300 bar
• Approximate Shipping Pack Weight: 0.20 kg to 0.28 kg

Who is the S&B Sellier & Bellot 8x57 JRS Rimmed Unprimed Brass Cases 20 Pack for?

• Break-Action Rifle Handloaders — requires an engineered rimmed design and a standard Large Rifle Boxer primer pocket to reliably feed, fire, and extract through traditional combination guns, drillings, double rifles, and single-shot Kipplauf rifles chambered in 8x57 JRS.
• Medium-to-Large Game Hunters — loads .323-inch diameter projectiles into this 8x57 JRS rifle brass case to achieve the terminal ballistics needed for harvesting deer and feral pigs at practical hunting distances out to 500 metres.

Less suitable for: Bolt-action rifles requiring a standard flush-rim interface, as well as older European firearms featuring .318-inch ("I" or "JR") bore diameters where firing .323-inch bullets risks exceeding the 3,300 bar receiver pressure limit; for those applications, use dedicated rimless 8x57 JS brass cases or firearms chambered for .318-inch components instead.