Weatherby Magnum

This proprietary cartridge was introduced by Weatherby in the late 1940s. As with most Weatherby designs, this cartridge case is notably "overbore" in case capacity. As a result only the slowest powders will give consistent ballistics in this cartridge.

Accurate 8700 is the best choice for all bullet weights in the .257 Weatherby Magnum. While higher velocities can be obtained with a light bullet using faster propellants, the air space resulting from the lower charge weight when using these propellants is not conducive to the same degree of consistency as that produced by 8700.

There is no SAAMI pressure limit for the .257 Weatherby Magnum. Weatherby factory ammunition produced 63,000 P.S.I. in our test barrel. These loads do not exceed that pressure.

.257 WEATHERBY MAGNUM

Gun

DOUGLAS

Max Length

2.560"

Barrel Length

26"

Trim Length

2.530"

Primer

FC 215

OAL Max

3.250"

Case

WBY

OAL Min

START LOADS

MAXIMUM LOADS

Cartridge

Bullet

Powder

Grains

Vel.

Powder

Grains

Vel.

P.S.I.

Length

Comment

BAR 85-X

4350

61.8

3490

4350

65.0

3713

62,000

3.150"

3100

66.5

3435

3100

70.0

3654

61,200

8700

85.5

3318

8700

90.0

3530

51,500

Compressed

HDY100 SP

4350

59.4

3301

4350

62.5

3512

61,100

3.180"

3100

65.6

3253

3100

69.0

3461

58,500

8700

85.5

3173

8700

90.0

3375

58,000

Compressed

NOS 115 SP

4350

56.1

3051

4350

59.0

3246

59,600

3.255"

*

3100

63.7

3086

3100

67.0

3283

61,100

8700

81.7

3130

8700

86.0

3330

55,300

Compressed

SPR 120 SBT

4350

56.1

2999

4350

59.0

3190

60,100

3.215"

3100

62.7

3018

3100

66.0

3211

61,100

8700

80.8

3067

8700

85.0

3263

55,600

Compressed

* Over Recommended MAX OAL

* Over Recommended MAX OAL

260 REMINGTON

The .260 Remington cartridge was wildcatted out of either .243 Winchester or .308 Winchester cases in various guises and names, the most common being the 6.5-08 which is an excellent description. The .260 is basically the .308 Win parent case-necked down to use a 6.5mm bullet. The 6.5mm on the 308 case has become quite a popular cartridge for High Power Rifle Silhouette competition. It combines good trajectory with adequate bullet weight and moderate recoil. Obviously, with it's ballistics, the 140 grain SP factory load is good for deer sized big game.

As a side note regarding bullet selection, bullets either heavier or longer than those shown are not deemed suitable. At least, not at the recommended O.A.L. required to fit in the magazines of the Remington rifles chambered for it. Deep seating with a large portion of the bullet intruding into the powder space below the case neck is not conducive to consistent internal ballistics. Generally, loads about 1.0 grain below the listed maximum charge weight were the most consistent of those tested.

SAAMI has established a maximum Average Pressure for the .260 Remington of 60,000 PSI. Remington's maximum O.A.L. for the .260 is 2.800". All of the bullets tested were seated so as not to be in contact with the rifling in our industry test barrel and to fit in the magazine of a Remington rifle.

.260 REMINGTON

Gun

HS PRECISION

Max Length

2.035"

Barrel Length

24"

Trim Length

2.025"

Primer

Remington 91/2

OAL Max

2.800"

Case

Remington

OAL Min

2.650"

START LOADS

MAXIMUM LOADS

Cartridge

Bullet

Powder

Grains

Vel.

Powder

Grains

Vel.

P.S.I.

Length

Comment

SRA85 HP

5744

__

__

5744

20.0

2160

22,300

2.670"

5744

29.7

2828

5744

33.0

3214

57,800

4064

39.6

2947

4064

44.0

3349

58,700

2700

43.2

2939

2700

48.0

3340

58,700

4350

43.2

2837

4350

48.0

3224

51,100

Compressed

3100

43.2

2571

3100

48.0

2922

41,200

Compressed

START LOADS

MAXIMUM LOADS

Cartridge

Bullet

Powder

Grains

Vel.

Powder

Grains

Vel.

P.S.I.

Length

Comment

HDY 100 SP

4064

38.7

2787

4064

43.0

3168

58,300

2.750"

2700

42.3

2794

2700

47.0

3176

58,400

4350

44.1

2874

4350

49.0

3266

59,000

Compressed

3100

45.0

2676

3100

50.0

3042

51,000

Compressed

BAR 100 X

4064

37.3

2719

4064

41.5

3090

57,200

2.750"

2700

38.5

2635

2700

42.8

2995

56,500

4350

43.2

2840

4350

48.0

3228

59,500

Compressed

3100

45.0

2744

3100

50.0

3119

57,200

Compressed

NOS 100 BT

4064

36.9

2713

4064

41.0

3083

56,900

2.765"

2700

40.5

2746

2700

45.0

3121

58,900

4350

43.2

2845

4350

48.0

3234

58,700

Compressed

3100

45.0

2698

3100

50.0

3066

52,800

Compressed

NOS 100 PART

4064

37.8

2781

4064

42.0

3161

59,200

2.720"

2700

41.0

2783

2700

45.5

3163

59,600

4350

43.6

2885

4350

48.5

3279

59,800

Compressed

3100

45.0

2720

3100

50.0

3091

53,200

Compressed

SRA 107 HPBT

5744

--

--

5744

18.0

1899

23,500

2.800"

5744

27.9

2527

5744

31.0

2872

55,400

4064

37.8

2716

4064

42.0

3087

58,100

2700

41.4

2722

2700

46.0

3094

58,200

4350

43.2

2797

4350

48.0

3179

58,900

Compressed

3100

43.2

2525

3100

48.0

2870

45,700

Compressed

SWF 120 SP

4064

35.1

2478

4064

39.0

2817

58,100

2.710"

2700

38.7

2487

2700

43.0

2827

57,200

4350

41.0

2600

4350

45.5

2955

58,700

3100

42.7

2507

3100

47.5

2849

53,700

Compressed

NOS 120 BT

4064

34.2

2427

4064

38.0

2758

58,200

2.800"

2700

37.8

2468

2700

42.0

2805

58,700

4350

40.0

2594

4350

44.5

2948

60,000

3100

43.2

2564

3100

48.0

2914

57,900

Compressed

SPR120 SP

4064

34.6

2456

4064

38.5

2791

59,000

2.750"

2700

38.7

2499

2700

43.0

2840

58,100

4350

40.5

2600

4350

45.0

2955

59,900

3100

43.2

2544

3100

48.0

2891

56,700

Compressed

BAR 120 X

4064

33.3

2368

4064

37.0

2692

58,500

2.750"

2700

37.8

2410

2700

42.0

2739

57,200

4350

39.6

2543

4350

44.0

2890

60,000

3100

41.0

2462

3100

45.5

2798

57,300

Compressed

NOS 125 PART

4064

34.6

2430

4064

38.5

2762

59,000

2.780"

2700

37.8

2439

2700

42.0

2772

56,700

4350

40.5

2584

4350

45.0

2937

60,000

3100

43.2

2563

3100

48.0

2913

58,700

Compressed

HDY 129 SP

4064

34.2

2362

4064

38.0

2685

59,100

2.780"

2700

36.9

2366

2700

41.0

2689

57,100

4350

39.6

2493

4350

44.0

2833

58,400

3100

42.3

2547

3100

47.0

2895

56,600

Compressed

START LOADS

MAXIMUM LOADS

Cartridge

Bullet

Powder

Grains

Vel.

Powder

Grains

Vel.

P.S.I.

Length

Comment

BAR 130 X

4064

31.2

2170

4064

34.7

2467

59,200

2.750"

2700

36.0

2264

2700

40.0

2573

58,100

4350

36.4

2323

4350

40.5

2640

58,600

3100

39.1

2324

3100

43.5

2642

57,500

SWF 140 SP

4064

31.5

2194

4064

35.0

2494

58,600

2.740"

2700

35.1

2229

2700

39.0

2534

57,300

4350

37.3

2351

4350

41.5

2672

58,000

3100

40.5

2323

3100

45.0

2640

54,900

Compressed

SPR 140 SP

4064

31.5

2170

4064

35.0

2467

58,400

2.750"

2700

35.1

2242

2700

39.0

2548

58,600

4350

36.9

2348

4350

41.0

2669

59,600

3100

40.5

2362

3100

45.0

2685

59,700

Compressed

NOS 140 PART

4064

32.4

2235

4064

36.0

2540

58,900

2.780"

2700

36.0

2295

2700

40.0

2609

59,700

4350

38.2

2405

4350

42.5

2733

59,400

3100

40.5

2390

3100

45.0

2717

57,800

Compressed

SRA140 SBT

4064

32.4

2200

4064

36.0

2501

53,700

2.750"

2700

35.1

2270

2700

39.0

2580

57,200

4350

39.1

2413

4350

43.5

2743

59,100

3100

41.4

2356

3100

46.0

2678

55,100

Compressed

HDY 140 SP

4064

32.8

2215

4064

36.5

2518

56,000

2.750"

2700

36.0

2271

2700

40.0

2581

58,000

4350

39.1

2412

4350

43.5

2742

60,000

3100

41.4

2379

3100

46.0

2704

57,400

Compressed

SRA 140 HPBT

4064

32.8

2260

4064

36.5

2569

57,600

2.775"

2700

36.0

2302

2700

40.0

2617

58,500

4350

38.7

2434

4350

43.0

2767

60,000

3100

41.4

2406

3100

46.0

2735

57,800

Compressed

SRA 142 HPBT

4064

33.7

2259

4064

37.5

2568

57,200

2.800"

2700

36.9

2323

2700

41.0

2640

58,800

4350

38.7

2414

4350

43.0

2744

57,500

3100

41.4

2354

3100

46.0

2676

54,600

Compressed

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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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