Belted Case
Definition
Cartridge case with a raised band (belt) ahead of the extractor groove that controls headspace; found in large-calibre magnum cartridges including .300 Winchester Magnum and .338 Lapua Magnum.
- Feature
- Raised band ahead of the extractor groove
- Function
- Controls headspace
- Common calibres
- .300 Winchester Magnum, .375 H&H Magnum
- Category
- Large-calibre magnum cartridges
Common questions
Why did belted cases become common on early magnum cartridges specifically?+
Many early magnum designs used a shoulder with a shallow taper, which made headspacing on the shoulder alone less precise. The belt gave a reliable, machinable headspace reference near the case head, a solution later cartridges with a more pronounced shoulder often no longer need.
How does a belted case help in cartridge identification during a firearms examination?+
The belt is a visually and tactilely distinct feature on a fired or unfired case, so it narrows the cartridge family quickly, in combination with case length, rim diameter, and headstamp, before more detailed measurement or headstamp reference comparison confirms the exact calibre.
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