Weatherby 25 WBY RPM 107gr Hammer HBC – Superb 20 Round Box

Description

Weatherby 25 WBY RPM 107gr Hammer HBC is the light, fast option in Weatherby 25 RPM lineup. The 107 grain Hammer HBC custom bullet leaves the muzzle at 3350 fps with a G1 ballistic coefficient of 0.510, which works out to roughly 2667 ft-lbs. Twenty rounds to the box, catalogued as M25RPM107HCB.

• What RPM Means and Why It Matters
• Weatherby 25 WBY RPM 107gr Hammer Specifications
• Honest Notes on the 25 RPM

What RPM Means and Why It Matters

RPM stands for rebated precision magnum. The case uses a rebated rim sized to a standard magnum bolt face while the body holds magnum capacity, which lets Weatherby build a genuinely fast cartridge on a lighter, shorter action than a belted magnum needs. The 25 RPM follows the same design thinking that made the 6.5 RPM and 338 RPM work.

The 107 grain Hammer HBC is a machined monolithic bullet rather than a conventional lead core projectile. Hammer builds them from solid copper with a very long ogive, which is where the 0.510 ballistic coefficient comes from at such a light weight. Driven at 3350 fps this 25 Weatherby RPM ammo shoots exceptionally flat and holds velocity well past 500 yards.

A quarter bore at this speed is a serious open country deer and antelope combination. It recoils noticeably less than a 7mm or 30 calibre magnum, which matters if you are shooting from field positions, and the light monolithic bullet gets to the target quickly enough that wind calls stay forgiving.

Weatherby 25 WBY RPM 107gr Hammer Specifications

Weatherby loads this on brass cases. The Hammer HBC bullet is solid copper and therefore lead free, which is useful in non lead hunting zones. Published figures come from a 26 inch test barrel.

• Manufacturer part number: M25RPM107HCB
• Line: Weatherby Select Plus
• Caliber: 25 Weatherby RPM
• Bullet weight: 107 grains
• Bullet type: Hammer HBC custom, solid copper monolithic
• Muzzle velocity: 3350 fps
• Approximate muzzle energy: 2667 ft-lbs
• Ballistic coefficient G1: 0.510
• Case material: brass
• Lead free: yes
• Bullet diameter: 0.257 inches
• Minimum twist rate: 1-8 inches
• Quantity: 20 rounds per box
• UPC: 747115463411

Honest Notes on the 25 RPM

Availability is the honest headline. The 25 Weatherby RPM is a young, proprietary cartridge and factory ammunition comes from one source. It is not something you will find at a counter on a hunting trip, and if a load works in your rifle it is worth buying several boxes at a time rather than assuming supply.

Monolithic bullets behave differently from lead core and it is worth knowing before the season. Solid copper holds together and penetrates deeply, but it needs impact velocity to open properly. At extreme range or out of a shorter barrel, Weatherby 25 WBY RPM 107gr Hammer HBC may pass through without the expansion a lead core bullet would give. Know your velocity at the distance you intend to shoot.

A 107 grain bullet is light for a cartridge with this much case capacity. It is superb on deer, antelope and open country coyotes, and it is not what most people would choose for elk. Weatherby loads a heavier 117 grain Hornady SST in the same cartridge for that reason, and it is the better pick if bigger game is on the list.

Barrel life is worth budgeting for. A quarter bore pushing 3350 fps runs hot, and throat erosion arrives sooner than it would in a milder cartridge. Let the barrel cool between strings, keep the round count honest, and expect to rebarrel earlier than you would with a standard 25-06.

For heavier game the same cartridge is loaded with a 117 grain Hornady SST. Full published ballistics for the cartridge are on the Weatherby 25 RPM page.

Weatherby 25 WBY RPM 107gr Hammer HBC suits deer and antelope hunters running a Weatherby Mark V or 307 chambered in 25 RPM who want a flat shooting, light recoiling lead free load. MAG5 Firearms is a family owned FFL in Collegeville, Pennsylvania. Boxes ship where state and local law allows.