Weatherby Select Plus Hammer Custom 25 Wby RPM 107-grain ammunition (part no. M25RPM107HCB) pairs Weatherby’s rebated precision magnum cartridge with a premium solid-copper hunting bullet built by Hammer. The 25 RPM follows the same design philosophy as the 6.5 and 338 RPM cartridges, a rebated case built to deliver magnum-level velocity from the lightweight Mark V 6-lug action without the bulk of a full magnum receiver. Weatherby loads it with a 107-grain Hammer Custom bullet, CNC-turned from a solid copper blend and individually weighed and measured for exacting consistency. The hollow-point design initiates expansion immediately on impact, shedding petals while the blunt-nosed base stays intact for a deep, controlled wound channel. At 3350 fps, this is a rifle ammunition load engineered specifically for Weatherby’s flat-shooting magnum platforms.

Key Specifications

• The chambering is 25 Wby RPM, a rebated precision magnum cartridge built for the lightweight Mark V 6-lug action.
• The bullet is a 107-grain Hammer Custom, a solid copper-alloy design CNC-turned for precision.
• Each bullet is individually weighed and measured, giving lot-to-lot consistency most factory ammunition does not offer.
• The hollow-point tip initiates immediate expansion, shedding petals on impact for a wide wound channel.
• The bullet’s blunt-nosed base stays intact, driving deep, controlled penetration after the petals separate.
• Muzzle velocity runs 3350 fps, magnum-class speed from a rebated case built for a lighter rifle.
• Each box holds 20 rounds, enough to develop a load and still head to the field.

Frequently Asked Questions

What makes the 25 RPM different from a standard 25-caliber magnum? Its rebated case is built to deliver magnum velocity from the lighter Weatherby Mark V 6-lug action instead of a full-size magnum receiver.

How does the Hammer Custom bullet perform on impact? The hollow point sheds its petals immediately while the solid-copper base stays intact, combining a wide wound channel with deep penetration.

Is this bullet lead-free? Yes, Hammer Custom bullets are CNC-turned from a solid copper alloy.

Buy Weatherby Select Plus Hammer Custom 25 Wby RPM Ammunition

The 25 RPM platform is still new enough that finding a purpose-built hunting load matters, and Weatherby’s own Hammer Custom loading is tuned specifically for it. Zero it in before the season and trust the petal-and-base design to do the rest on game day. Order from our Lubbock, Texas gun shop and it ships fast to your door.