Reload Image

Reload Image

Like most shooters, I have a few favorite calibers. None of them is of the “extreme” nature—meaning that the weight of the powder charge is over half the weight of the bullet. My favorite calibers include such standbys as the .223 Remington, .308 Winchester and 7×57 Mauser. Also in that list is another of the “mild” cartridges, the .257 Roberts.

With a wide assortment of bullets available in .257 caliber, the handloader can tailor ammunition for use on targets from small varmints to medium game. Left to right: 70-grain Sierra BlitzKing, 75-grain Hornady V-Max, 75-grain Hornady hollow point, 75-grain Sierra hollow point, 85-grain Nosler Ballistic Tip, 87-grain Speer TNT and 87-grain Hornady spitzer bullets.

With a wide assortment of bullets available in .257 caliber, the handloader can tailor ammunition for use on targets from small varmints to medium game. Left to right: 70-grain Sierra BlitzKing, 75-grain Hornady V-Max, 75-grain Hornady hollow point, 75-grain Sierra hollow point, 85-grain Nosler Ballistic Tip, 87-grain Speer TNT and 87-grain Hornady spitzer bullets.

Several .25-caliber cartridges have achieved some popularity, but not many. The lure of the .30 caliber has overshadowed the .25, and only the .25-35 Winchester, .250 Savage and .257 Roberts have reached and maintained a level of popularity over a duration of time.

More-recent .25-caliber developments include the .25-06 Remington, .25 Winchester Super Short Magnum and .257 Weatherby Magnum. Except for the .25-06, they are not selling like hot cakes; and except for nostalgia allure, the .25-35 Winchester and .250 Savage are seldom seen.

Necking Down

Changing the neck diameter on an existing case has resulted in a great number of cartridges. For example, that procedure has resulted in the .243 Winchester, .260 Remington, 7mm-08 Remington and .358 Winchester being produced from the .308 Winchester.

Numerous other examples could be cited, but the point is that it has been a long-standing practice to do so. Whereas the .25-06 Remington resulted from necking down a .30-06 case, changing dimensions slightly and necking down an even older cartridge, the 7×57 Mauser, to .25 caliber resulted in the .257 Roberts. It is named after the main proponent of the cartridge, Ned Roberts, whose work in the 1920s resulted in Remington making the .257 Roberts a factory round in 1934.

The .257 Roberts case (right) is a necked-down version of the 7x57 Mauser (left).

The .257 Roberts case (right) is a necked-down version of the 7×57 Mauser (left).

How did the .257 Roberts fare in days gone by? For many years, the acknowledged champion of gun writers was Jack O’Connor, who had this to say about the .257: “Of all the cartridges, both standard and wildcat, that have been cooked up in the last 30 years there is none that can play more and sweeter tunes than the .257” (Sportsman’s Arms and Ammunition Manual, Popular Science Books, 1952, p. 23).

In the cartridge introduction in the Speer Reloading Manual No. 7, 1966, these words are found: “One of the most useful cartridges ever developed is the .257 Roberts.”


Did the physical nature of the world and its fauna change in the last 50 to 70 years so that the .257 Roberts is no longer a viable tool? Not hardly!

What happened is that shooters became enamored with velocity; and with improvements in optics, hunters started taking longer shots. In such cases, higher velocity means flatter trajectory.

Along with these changes, there appeared the .243 Winchester and .244 Remington, which later became the 6mm Remington. Having bullet diameters of .243 inch and loaded to higher pressure than the .257, they gave a slight advantage in the velocity race with bullets having the same sectional density.

The .257 Roberts has long been a favorite for use on larger varmints such as coyotes.

The .257 Roberts has long been a favorite for use on larger varmints such as coyotes.

Ever quick to gravitate to new cartridges, shooters jumped on the .243 Winchester, which was designed to be a varmint and deer cartridge with bullets weighing 80 and 100 grains. The original .244 Remington utilized a slower twist to stabilize varmint-weight bullets, which was corrected by changing the twist and renaming the cartridge. But it was too little too late; and the .243 is enormously popular, whereas the 6mm is rarely seen in a new rifle.

Kimber offers the Hunter, Classic and Mountain versions of its bolt-action rifles in .257 Roberts; and, until recently, Ruger marketed the Model 77 Hawkeye in .257 Roberts. My most recent sighting of a new .257 Roberts was a Ruger No. 1 International with a full-length Mannlicher stock.

Cartridges have pressure limits that are established by the Sporting Arms and Ammunition Manufacturers Institute (SAAMI). The pressure limit for the .308 Winchester is 62,000 psi, whereas that of the 7mm Mauser is 51,000. As a result, the pressure limit for the 243 Winchester was established as 60,000 psi, but that of the .257 Roberts was only 54,000 psi.

Realizing that modern rifles can be chambered for either of those cartridges led Winchester to introduce the .257 Roberts +P that has a pressure limit of 58,000 psi, and the cartridges have that headstamp. The older non +P Winchester cases have an average weight of 159.4 grains, whereas the newer +P cases have an average weight of 171.2 grains. The Remington cases I weighed averaged 168.8 grains, which is comparable to that of the Winchester +P cases. Newer .257 Roberts cases have smaller volume than do the older versions.


When it comes to performance, most shooters could be handed a rifle sighted in at perhaps 200 yards and, with appropriate loads, not see any difference between the .243 Winchester and .257 Roberts in the field.

For long-range varmint shooting, the .243 Winchester has the edge because of somewhat higher velocity with lighter bullets. For use on medium game, the .257 Roberts might be slightly better, because it can be used with heavier bullets of larger diameter.

There are many factory loads available for the .243 Winchester, but the choice in .257 Roberts is much more limited. Therefore, if an owner of a .257 Roberts wants to increase its versatility and maximize its potential, handloading is the best option.

The 7mm Mauser case is of moderate size, but when it is necked to .257 caliber, the volume is rather large for the diameter. This means that relatively slow-burning powders work best, and powders such as Alliant Reloder 15, 17, 19; Power Pro 2000-MR, IMR 4320, 4064, 4350 and 8208 XBR; Accurate 4350, Hodgdon H4350 and H380; and CFE 223 are all suitable.

All the loads listed in the accompanying table (see the sidebar on page XXX) were assembled using Winchester +P cases and Winchester large rifle primers. Velocities were measured at 10 feet from the muzzle using a Competition Electronics ProChrono chronograph. The load parameters and results are listed in the accompanying table.

These results were obtained using .257 Roberts loads in a Ruger 77 with a 22-inch barrel.

Bullet Length (inches)      Powder Charge Grains Velocity (fps)
60 gr Hornady FP 2.521     Alliant 2400 14 1,899
70 gr Sierra BlitzKing 2.775     IMR 8208 XBR 41 3,228
70 gr Sierra BlitzKing 2.775     Winchester 760 47.2 3,173
75 gr Hornady HP 2.749     Hodgdon BL-C(2) 40 2,945
75 gr Sierra HP 2.765     Varget 39 2,912
75 gr Sierra HP 2.756     IMR 4064 39 3,012
75 gr Hornady V-Max 2.78     IMR 4064 41.7 3,193
75 gr Hornady V-Max 2.78     Alliant Reloder 17 46.5 3,228
85 gr Nosler Ballistic Tip 2.776     IMR 4064 40 3,086
87 gr Hornady SP 2.77     Varget 38.4 2,878
87 gr Speer TNT 2.777     Power Pro 2000 MR 42.5 2,947
90 gr Speer HP 2.762     IMR 4955 48 3,225
100 gr Speer SP 2.771     IMR 4955 46.5 3,112
100 gr Speer SP 2.757     Accurate 4350 42.7 2,572
117 gr Sierra BTSP 2.775     IMR 4955 43 2,758
117 gr Sierra BTSP 2.768     Accurate 4350 41.2 2,564
Note: The average velocity is for five shots. (These loads were safe and reliable in the author’s rifle, but neither the author nor the publisher accepts any responsibility for their preparation and use by others. They should be assembled only in cases marked +P and fired only in modern rifles. These loads should be approached with caution and using good reloading practices.)

From data shown in the table, it can be seen that the .257 Roberts is a versatile cartridge that is quite at home in both varmint-hunting and medium-game situations. The loads with lighter bullets give up very little to the .243 Winchester, and those with bullets of 100 to 117 grains are not far behind similar loads for the .260 Remington or 6.5 Creedmoor. However, the latter calibers can utilize heavier bullets. In my rifle, the most accurate load is with the 75-grain Sierra hollow point and 39.0 grains of IMR 4064. That load routinely gives groups of 1 inch or less.

Although some compilations of data might show slightly higher velocity for 117-grain loads, the load using IMR 4955 gave 2,758 fps. That is sufficiently potent to make the .257 Roberts effective on deer-sized game.

The load using the 60-grain bullet is intended for short range on pests, and it performed superbly. (When assembling reduced loads, insert a bullet immediately after placing powder in the case so there is no possibility of a double charge!) The velocities were very uniform, and at 50 yards, a cluster of five shots measured slightly over ½ inch. With some of the other loads in which 75-grain bullets were used, the .257 Roberts can be an effective varmint rifle at short or long ranges.

Sweet Tunes

In comparison to some of the hotshots of today, the .257 Roberts is a relatively mild cartridge. However, with the wide range of available bullet weights, it is a versatile cartridge that is still a good choice for the average hunter who takes shots inside of 300 yards and hunts game no larger than deer. And, of course, it doubles as an excellent varmint cartridge, especially for larger predators.

It is still a useful cartridge, and it can play “sweet tunes.” No, it is not a super magnum, but for a lot of hunting, a mild, light-recoiling .257 Roberts is all that is needed.


Editor’s note: A version of this article first appeared in the November 2017 print issue of Gun World Magazine.