CMMG
Overview
The CMMG Barrel and BCG KIT 8in 4140CM SBN 57 X 28mm is a barrel. Compare prices from multiple merchants and find the best deal.
Specifications
Available Merchants(8)
Prices checked
Price Alert
Build history on GunPartPicker
Builders on GunPartPicker first added the CMMG Barrel and BCG KIT 8in 4140CM SBN 57 X 28mm to a build in May 2026.
Availability is good: it was in stock at one retailer or another nearly every day in September 2026, but today 2 of the 8 retailers we track have it in stock. Prices barely moved in September 2026, holding around $359.99, so there haven't been real sales lately. Buying today, the lowest price is $402.97 at GritR Sports, above September's low of $354.64, so a better deal may come back.
Updated · from real builds on GunPartPicker · Prices checked · refreshed daily across 37 retailers
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