Roberts

Originally designed by Ned Roberts during the 1930s, the .257 Roberts is based on the 7x57mm Mauser necked to .25 caliber. When Remington introduced the commercial version of this cartridge in 1934, they changed the shoulder angle from 15° to 20°. The .257 Roberts was originally introduced in Remington's Model 30 bolt action rifle. Remington also produced the Model 722 bolt action and 760 Gamemaster pump chambered for this cartridge, as well as a limited run of the Model 700 Classic. Winchester chambered both their Model 54 and Model 70 rifles for this cartridge. Other manufacturers have likewise chambered for it.

While not as popular today as it once was, the .257 Roberts is an all-around cartridge for the handloader. It is an excellent long-range varmint cartridge and is suitable for large game up to and including black bear.

The SAAMI Maximum Average Pressure for the .257 Roberts cartridge is 54,000 P.S.I. Factory ammo produced 47,000 P.S.I in our test barrel. These loads do not exceed that pressure.

.257 ROBERTS

Gun

DOUGLAS

Max Length

2.233"

Barrel Length

24"

Trim Length

2.213"

Primer

CCI 200

OAL Max

2.775"

Case

REM

OAL Min

2.620"

START LOADS

MAXIMUM LOADS

Cartridge

Bullet

Powder

Grains

Vel.

Powder

Grains

Vel.

P.S.I.

Length

Comment

90 (L) GC

5744

17.0

1851

5744

22.0

2275

21,300

2.625"

Penny's

RCBS 100 (L) GC

5744

17.0

1756

5744

24.0

2301

27,800

2.705"

Penny's

8700

47.7

2174

8700

53.0

2471

32,200

2.660"

SRA 75 HP

2520

35.6

2789

2520

39.5

3169

42,100

2.745"

4064

38.1

2904

4064

42.3

3300

47,000

2700

43.7

3048

2700

46.0

3243

44,800

4350

42.3

2866

4350

47.0

3257

43,600

3100

45.9

2783

3100

51.0

3163

38,100

Compressed

START LOADS

MAXIMUM LOADS

Cartridge

Bullet

Powder

Grains

Vel.

Powder

Grains

Vel.

P.S.I.

Length Comment

BAR 85-X

2520

33.8

2622

2520

37.5

2980

44,000

2.770"

4064

36.4

2677

4064

40.5

3043

45,800

2700

40.9

2868

2700

43.0

3051

44,100

4350

41.4

2728

4350

46.0

3100

44,500

3100

44.1

2667

3100

49.0

3031

39,900

SRA 90 HPBT

2520

33.3

2593

2520

37.0

2947

43,500

2.735"

4064

36.4

2694

4064

40.5

3062

46,200

2700

39.9

2810

2700

42.0

2989

42,700

4350

40.5

2641

4350

45.0

3001

42,100

3100

45.0

2689

3100

50.0

3056

44,000

Compressed

BAR 100-X

2520

30.6

2324

2520

34.0

2641

42,700

2.760"

4064

34.2

2460

4064

38.0

2796

45,800

2700

37.1

2522

2700

39.0

2683

42,700

4350

36.9

2410

4350

41.0

2739

42,700

3100

41.4

2381

3100

46.0

2706

37,800

NOS 100 BT

2520

31.5

2416

2520

35.0

2745

43,400

2.785" *

4064

34.9

2534

4064

38.8

2880

47,000

2700

39.0

2683

2700

41.0

2854

44,000

4350

40.1

2550

4350

44.5

2898

44,100

3100

44.1

2520

3100

49.0

2864

39,900

Compressed

SRA117SBT

2520

30.6

2248

2520

34.0

2555

42,700

2.775"

4064

31.5

2235

4064

35.0

2540

46,500

2700

37.1

2462

2700

39.0

2619

43,200

4350

38.7

2376

4350

43.0

2700

44,100

3100

43.2

2408

3100

48.0

2736

43,700

Compressed

* Over SAAMI Maximum OAL

* Over SAAMI Maximum OAL

257 ROBERTS C+P)

This data is only for use in modern firearms approved, by a gunsmith or manufacturer, for use with higher pressure +P ammo.

The SAAMI Maximum Average Pressure for the .257 Roberts +P is 58,000 P.S.I. Factory +P ammo produced 51,000 P.S.I. in our test barrel. These loads do not exceed that pressure.

.257 ROBERTS (+P)

Gun

DOUGLAS

Max Length

2.233"

Barrel Length

24"

Trim Length

2.213"

Primer

CCI 200

OAL Max

2.775"

Case

REM

OAL Min

2.620"

START LOADS

MAXIMUM LOADS

Cartridge

Bullet

Powder

Grains

Vel.

Powder

Grains

Vel.

P.S.I.

Length Comment

SRA 75 HP

2520

36.9

2912

2520

41.0

3309

48,100

2.745"

4064

39.0

2966

4064

43.3

3370

51,000

2700

44.7

3119

2700

47.0

3318

48,600

4350

44.1

2966

4350

49.0

3370

47,200

BAR 85-X

2520

35.1

2709

2520

39.0

3078

48,700

2.770"

4064

37.3

2750

4064

41.5

3125

49,000

2700

42.8

2959

2700

45.0

3148

48,700

4350

42.3

2802

4350

47.0

3184

48,900

SRA 90 HPBT

2520

34.7

2692

2520

38.5

3059

48,200

2.735"

4064

37.3

2755

4064

41.5

3131

49,400

2700

41.8

2954

2700

44.0

3143

50,300

4350

42.3

2786

4350

47.0

3166

49,900

NOS 100 BT

2520

33.8

2525

2520

37.5

2869

48,700

2.785" *

4064

36.0

2594

4064

40.0

2948

50,800

2700

40.9

2761

2700

43.0

2937

49,200

4350

41.9

2682

4350

46.5

3048

50,800

BAR 100-X

2520

33.3

2475

2520

37.0

2813

49,900

2.760"

4064

35.1

2533

4064

39.0

2879

49,600

2700

39.0

2640

2700

41.0

2808

47,800

4350

39.6

2570

4350

44.0

2920

50,300

3100

43.2

2577

3100

48.0

2928

47,800

Compressed

START LOADS

MAXIMUM LOADS

Cartridge

Bullet

Powder

Grains

Vel.

Powder

Grains

Vel.

P.S.I.

Length

SRA117SBT

2520

32.9

2357

2520

36.5

2678

49,300

2.775"

4064

33.7

2347

4064

37.5

2668

49,300

2700

39.0

2532

2700

41.0

2694

48,000

4350

39.6

2410

4350

44.0

2739

48,400

* Over SAAMI Maximum OAL

Hunting Mastery Selected Tips

Hunting Mastery Selected Tips

Deer hunting is an interesting thing that reminds you of those golden old ages of 19th centuries, where a handsome hunk well equipped with all hunting material rides on horse searching for his target animal either for the purpose of displaying his masculine powers or for enticing and wooing his lady love.

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