▼ 23% below avg
CMMG Mk4 AR-15, LR-308 Buffer Tube Lock Ring
Lowest Price
$7.41
MSRP
$8.95
Savings
17% off
Verified In Stock at
10 Stores
Updated
Aug 26, 2026
Compare Deals from 18 Retailers
Verified availability, then price
Lanbos Armory Best
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Code ARMSAGORA — 7% Off Most Items
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$9.29
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Castle Nut for Buffer Tubes
Fits AR-15
Matte black finish
Specifications
Description
CMMG offers replacement components for the AR-15 that are made to strict military specifications. These high quality components will provide excellent fit and reliable function in your AR series rifle and are perfect for upgrading existing components or replacing worn or broken parts.
