The RCBS .308 Win Small Base Die Set (Part Number: 15503) is a precision-engineered, two-piece mechanical reloading tool designed to resize and seat .308 Winchester and 7.62x51mm cartridge brass. Built from polished, heat-treated steel, this Group A die set is tailored to process fired brass so that it chambers and extracts reliably in firearms with demanding actions. Operating entirely mechanically, this die set requires no electrical power, making it fully compatible with standard Australian manual reloading setups without requiring electrical compliance or physical plug adaptors.

Key Features

• Small Base Sizing: Compresses the cartridge body and pushes the shoulder back by an additional few thousandths of an inch, sizing the lower web portion of the brass slightly below standard SAAMI minimum specifications to guarantee seamless chambering.
• Decapping and Expanding: The sizing die features an integrated expander-decapping unit that ejects spent primers while expanding the case neck to the correct bullet-holding tension.
• Built-In Roll Crimp: The regular bullet seating die features an integrated roll-crimp ring to secure projectiles, which can be deactivated by backing the die body out slightly.
• Standard Threading: Uses the industry-standard 7/8"-14 thread configuration, ensuring compatibility with the vast majority of progressive and single-stage reloading presses.

Product Specifications

• Calibre Compatibility: .308 Winchester / 7.62x51mm
• Thread Pitch: 7/8"-14 thread
• Set Components: Small Base Sizer Die (with expander-decapping unit) and Regular Bullet Seating Die (with roll-crimp ring)
• Package Dimensions: 13.5 x 11.2 x 3.8 cm
• Shipping Weight: 540 grams
• Material: Polished, heat-treated steel

Who is the Rcbs 308 Win Small Base Die Set for?

• Reloaders of semi-automatic and rapid-cycle firearms — resizing .308 Winchester / 7.62x51mm brass with this small base reloading die set compresses the cartridge body below standard minimums to ensure reliable feeding and extraction in semi-automatic, pump, or lever-action chambers.
• Shooters experiencing tight chamber clearances — utilizing this 540-gram small base reloading die set compresses the lower web of stubborn brass slightly below standard SAAMI dimensions to prevent chambering failures that standard full-length dies cannot resolve.

Less suitable for: ammunition intended strictly for bolt-action rifles. Using a small base reloading die set for bolt-action platforms can cause unnecessary brass fatigue and shorter case life; standard full-length sizing dies or neck-sizing dies are better suited for these firearms.