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CMMG Mk57 5.7x28mm Bolt Maintenance Kit 57AFF37 Caliber: 5.7x28mm, Gun Make: CMMG, 11% Off

CMMG Parts Kit, Bolt Maintenance, Mk57, 5.7x28mm, 57AFF37
CMMG Parts Kit, Bolt Maintenance, Mk57, 5.7x28mm, 57AFF37
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CMMG Parts Kit, Bolt Maintenance, Mk57, 5.7x28mm, 57AFF37

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13% OFF Bolt Carrier Groups

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Eligible models will have a savings offer and the coupon code to use below. Add the item to your cart and enter coupon code for savings on that select model! Limited time only. Cannot be combined with other promotions or offers.
Caliber:
5.7x28mm
Gun Make:
CMMG

Code: 2CM-ABA-CP65-57AFF37

MPN: 57AFF37

UPC: 816422029181

List: $51.99Save 12%
$45.99

Product Info for CMMG Mk57 5.7x28mm Bolt Maintenance Kit

Replacement parts for Mk57 (5.728) Bolt.image

WARNING: California`s Proposition 65

Specifications for CMMG Mk57 5.7x28mm Bolt Maintenance Kit:

Manufacturer: CMMG
Caliber: 5.7x28mm
Gun Make: CMMG

Package Contents:

  • CMMG Mk57 5.7x28mm Bolt Maintenance Kit
  • Mk57 (5.728) Extractor
  • Extractor Spring
  • Extractor Pin
  • 1-16? Roll Pin
  • Extractor Buffer
  • Mk57 (5.728) Ejector
  • Bolt Spring
  • Ejector Spring

CMMG Mk57 5.7x28mm Bolt Maintenance Kit Orderable Models

List of Orderable Models

  • CMMG Parts Kit, Bolt Maintenance, Mk57, 5.7x28mm, 57AFF37 , MPN: 57AFF37 , UPC: 816422029181 , Code: 2CM-ABA-CP65-57AFF37
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Last updated 2026-10-09 UTC.