How Does Weatherby’s New .25 RPM Stack Up Against Other Quarter-Bores?

But now, inexplicably, the quarter-bore is making a comeback. Hornady released their 25 Creedmoor in May of last year (click here for a deep dive into that cartridge), and just a few weeks ago, Weatherby came out with their own take on the .257–the 25 RPM.

I’ve been on the quarter-bore bandwagon for a while, but it’s not like hunters have been clamoring for more mid-power cartridges. Can Weatherby’s new offering give you an edge over other .25’s, or is it just a play to get ahead of the next hot ammo trend? Keep reading to find out.

Like the 25 Creedmoor, the 25 RPM (Rebated Precision Magnum) promises to modernize the quarter-bore. The 1:7.5” recommended barrel twist rate can stabilize 133-grain bullets even while traveling 3,000 feet-per-second (fps) at the muzzle. The large case body diameter, low body taper, and 35-degree shoulder mimic modern cartridges by maximizing efficiency, but it wouldn’t be a Weatherby cartridge if it didn’t also maximize velocity. The 25 RPM can push a 107-grain bullet (a more traditional weight for a quarter-bore) a whopping 3,350 fps at the muzzle, while the 117-grain pills scream along at 3,150 fps.

The 25 RPM is a necked-down version of the 6.5 RPM case, which is a derivation of the old 284 Winchester. That means the new 25 can use the same common bolt face as a .308 Win., 243 Win, 6.5 Creedmoor, and 7mm-08 Rem, but the overall length mimics the .300 Win. Mag. (3.34 inches). It’ll need a long action to accommodate that long cartridge, but that’s the price you pay for hitting those velocities.

Weatherby is currently offering the 25 RPM with four bullet options (velocities from a 24-inch barrel):

• 107g Hammer (polymer tip, solid copper) | BC: .510 | 3350 fps
• 117g Hornady SST (polymer tip, copper jacketed) | BC: .390 | 3150 fps
• 117g Barnes LRX (polymer tip, solid copper) | BC: .530 | 3150 fps
• 133g Berger Elite Hunter (copper jacketed) | BC: .613 | 3000 fps

A box of 20 will cost you between $80 and $110 if you order directly from Weatherby, and as of this writing, only the 117-grain Hornady SST is in stock. Big online retailers like Midway USA aren’t yet stocking the 25 RPM, though I’d expect that to change soon.

Here are some additional specs on the new cartridge:

• Bullet Diameter: .257 (6.35mm)
• Max OAL: 3.34”
• Case Length: 2.4 inches
• Bolt face: .477 inches
• Twist Rate: 1:7.5

There’s no doubt the 25 RPM is impressive, but how does it measure up against other quarter-bores, both old and new?

When stacked up against the 25 Creedmoor’s hunting bullet option (128-grain ELD-X), the 25 RPM has the Creed beat on velocity, energy, and trajectory–despite shooting a slightly heavier bullet.

It’s important to keep in mind that the 25 Creedmoor is only working with 60% of the 25 RPM’s case capacity. The fact that the Creed gets as close as it does is impressive, and the lighter charge will produce less recoil, which some will appreciate more than the extra velocity and energy. Still, if you’re looking for a quarter-bore that can really pack a punch, the 25 RPM will be a better option than the Creed.

I also pulled ballistic data for the 25-06 and 257 Weatherby Magnum and stacked them up against the 25 RPM and 25 Creedmoor using similar bullet weights.

As you can see, in this comparison at least, the 257 Weatherby Magnum has its newer counterpart beat in all three categories. That incredible 3,400 fps muzzle velocity allows the older cartridge to maintain a velocity and energy advantage out to 500 yards, and it also drops less at every distance.

Of course, much like the previous comparison, the 257 Wby. Mag. is working with more powder than the 25 RPM. Guns chambered in that cartridge are also unable to stabilize the high-BC, heavy-for-caliber bullets that the RPM is designed to shoot. Those bullets will buck the wind better at any distance, and if you increase the distance to about 700 yards, the RPM drops less than the older Magnum.

The RPM and the Creedmoor are remarkably similar in this comparison, but the 25-06 struggles to keep up. It performs relatively better with lighter bullets, but if you want something to compete with the RPM’s 117-grain options, it won’t be as fast, flat, or powerful as the newer option.

I haven’t had a chance to get my hands on the 25 Weatherby RPM, but if the published ballistic data pans out, it will be an excellent addition to the growing stable of quarter-bores. It offers the screaming hot velocities we’ve come to expect from Weatherby, but it also tempers those speeds in favor of heavy, high-BC bullets preferred by long-range shooters.

I still tend to favor the Creedmoor as a deer cartridge. It has more than enough juice for those critters, and its smaller case will produce less recoil than the RPM. The .25-06 also does a fine job accomplishing what many see as the quarter-bore’s niche: stepping down to predators and varmints with light, fast-shooting bullets and punching up to deer and other big game. If you already own either of these cartridges, the RPM won’t do that much more.

Still, it’s impossible to deny that Weatherby’s new cartridge offers more peace of mind for longer range shots, and its velocity and energy advantages make it more suitable for stepping up to larger animals like elk. Those 107-grain pills are absolutely screaming out of the barrel, and they’ll make quick work of whatever coyote happens to get in the way. It looks like a solid cartridge from a legendary company, so when it comes to hunting cartridges, I say, the more the merrier.