Weatherby Select Plus .338 WBY RPM 225gr Barnes TTSX

The .338 WBY RPM: Modern Magnum Innovation

Weatherbys .338 WBY RPM (Rebated Precision Magnum) represents a thoughtful evolution in magnum rifle design. Introduced in 2022, this cartridge was developed to solve a specific problem: delivering magnum performance in a lightweight backcountry rifle without sacrificing effectiveness on North Americas largest game animals.

Cartridge Design

The .338 RPM is based on the 6.5 RPM case, necked up to accommodate .338 caliber bullets. The engineering is purposeful:

• Large body diameter provides substantial powder capacity
• Low body taper maximizes internal volume
• 35-degree shoulder creates efficient case geometry
• Higher velocities result from increased powder capacity

This design allows the lightweight Mark V 6 Lug action to deliver true magnum ballistics without the weight penalty of traditional magnum rifles.

Ammunition Specifications

Weatherbys Select Plus line pairs this innovative cartridge with Barnes TTSX bullets—a proven choice for hunters who demand reliability and performance. The 225-grain TTSX bullet exits the muzzle at 2800 feet per second, delivering the velocity and energy needed for ethical, effective hunting across diverse terrain and game species.

The Right Choice

If you own a .338 WBY RPM rifle or are considering one, this ammunition represents the manufacturers recommended loading. Its engineered specifically for your rifle and the hunting situations youll encounter in the field.