What is the .300 Winchester Magnum?

The .300 Winchester Magnum is a factory rifle cartridge in the Winchester Magnum family, introduced in 1963.

What bullet diameter does the .300 Winchester Magnum use?

The .300 Winchester Magnum uses a bullet diameter of 0.308 inches.

What is the case type of the .300 Winchester Magnum?

The .300 Winchester Magnum has a Belted, Bottleneck case type.

What primer does the .300 Winchester Magnum use?

The .300 Winchester Magnum uses a Large Rifle (.210") primer.

What cartridges are in the Winchester Magnum family?

The Winchester Magnum family includes the .300 Winchester Magnum and other related cartridges. Browse the full family on OpenCartridge.

.300 Winchester Magnum

Rifle Factory

Family	Winchester Magnum
Year	1963
Case Type	Belted, Bottleneck
Primer	Large Rifle (.210")

Dimensions (inches)

Bullet Ø	0.308
Case Length	2.62
Neck Ø	0.334
Shoulder Ø	0.489
Base Ø	0.513
Rim Ø	0.529
Total Length	3.3

SAAMI Pressure

MAP (PSI)	64,000
MAP (CUP)	54,000

Parent Cases

.375 H&H Magnum

.300 H&H Magnum

External Reference

Muzzle Velocity across 8 loads: Avg 2996 fps Min 2702 fps Max 3253 fps

Community Load Data

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150.00gr Sierra Boat Tail (BT) — 61.50gr

by imported_data · Aug 12, 2026

3154 fps

3.3400 OAL"

N/A Case

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220.00gr Sierra Boat Tail Hollow Point (BTHP) — 65.50gr

by imported_data · Aug 12, 2026

2702 fps

3.4500 OAL"

Jagemann Case

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208.00gr Hornady Boat Tail Hollow Point (BTHP) — 68.30gr

by imported_data · Aug 12, 2026

2787 fps

3.4500 OAL"

Jagemann Case

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180.00gr Speer Boat Tail Soft Point (BTSP) — 71.80gr

by imported_data · Aug 12, 2026

2969 fps

3.3400 OAL"

Jagemann Case

PRO

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168.00gr Hornady Boat Tail Hollow Point (BTHP) — 72.50gr

by imported_data · Aug 12, 2026

3084 fps

3.3400 OAL"

Jagemann Case

PRO

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150.00gr Hornady Full Metal Jacket (FMJ) — 75.50gr

by imported_data · Aug 12, 2026

3253 fps

3.3150 OAL"

Jagemann Case

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190.00gr Sierra Match — 62.40gr

by imported_data · Aug 12, 2026

2907 fps

3.3400 OAL"

Jagemann Case

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168.00gr Sierra Boat Tail Hollow Point (BTHP) — 67.50gr

by imported_data · Aug 12, 2026

3113 fps

3.3400 OAL"

Jagemann Case

PRO

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