Firearms

CMMG Endeavor MK57 5.7x28mm 16-inch

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Specifications

About

Notable Variants

Aftermarket Ecosystem

Historically Significant Examples

Serial Number Data

Production data from factory records and collector research. Year ranges are approximate for pre-1968 firearms.

Years	Serial Range	Count	Factory	Country	Confidence

CMMG MK57 in 5.7x28mm, using Five-seveN-compatible magazines.

Type: Rifle

Action: Semi-Automatic

Caliber: 5.7x28mm

Capacity: 40

Year introduced: 2020, USA

Weight: 64 oz

Overall length: 32"

Status: Active

Intended use: Home defense, competition