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CMMG
Overview
The CMMG 16" M300 barrel is designed specifically for the 300 Blackout caliber, featuring a medium profile that balances weight and performance. With a carbine-length gas system and a twist rate of 1:7, this barrel provides reliable cycling and optimal stabilization for a variety of bullet weights, making it suitable for both supersonic and subsonic loads. This barrel commonly appears in builds focused on the 300 Blackout caliber, especially those where a carbine gas system is preferred.
Specifications
Available Merchants(9)
Prices checked
Price Alert
Build history on GunPartPicker
Availability is good: it was in stock at one retailer or another nearly every time we checked in October 2026, and today 7 of the 9 retailers we track have it in stock. It dipped to $176.99 at Ammunition Depot for a stretch in October 2026, under its usual $190.61 to $199.28, so sales do come around. Buying today, the lowest price is $176.79 at AT3 Tactical, which matches the best price we saw in October.
Prices checked · refreshed daily across 37 retailers
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Frequently Built With
The part most often added in each category by the builds that include this one
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Build Configuration Breakdown
Aggregated and anonymized data showing how builders use this product
PlatformBased on real build data showing which platform (AR-15, AR-10, AR-9) builders pair with this product.
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