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Vizards Guns and Ammo© Vizards Guns and Ammo
80Deal ScoreIn Stock

CMMG 55CA9CB Receiver Extension Castle Nut Black Matte MK4

$7.57
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Brand
CMMG
Color
Black
Category
Gun Parts
Gun Part Type
Lower Receiver
UPC
815835017426
MPN
55CA9CB

Overview

The CMMG Mk4 receiver extension castle nut is a precision-manufactured buffer tube assembly component designed for AR-platform rifle builds and upgrades. Constructed in a durable black matte finish, this lower receiver part ensures dimensional consistency and material quality to maintain tight tolerances critical for reliable bolt carrier travel, proper spring preload, and consistent cycling reliability across various ammunition types. Essential for builders and technicians, the lightweight design minimizes overall platform weight while maintaining structural integrity for tactical carbines, duty weapons, and precision training platforms.

Price & Stock History

Price — 90d
Listings In Stock — 30d

Reviews

No review data was found for this product.

Listings

Vizards Guns and AmmoBest Deal
In Stock
$7.57
Armed In Michigan
In Stock
$7.75
Brownells
No Stock
$8.46
MidwayUSA
In Stock
$8.59
Palmetto State Armory
In Stock
$8.79
City Arsenal
In Stock
$8.99
Hinterland Outfitters
No Stock
$9.00
X-Ring Supply
In Stock
$9.99
Governors Gun Club
In Stock
$10.80
Cheaper Than Dirt
In Stock
$10.89
Tactical Surplus USA
In Stock
$11.08
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