JMAC Customs RRD-4C KeyMount Muzzle Device w/ 1/2-28 Threads - RRD-4C-28F-KM
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Jmac Customs
Overview
The JMac Customs RRD-4C KeyMount muzzle device is designed specifically for 9mm calibers and features a 1/2x28 thread pitch, allowing for easy attachment to compatible barrels. This muzzle device effectively reduces recoil and muzzle rise, enhancing overall control during rapid firing. It's commonly used in builds that employ a carbine gas system and are chambered for 5.56 NATO, making it a versatile choice for those looking to optimize their performance.
Specifications
JMAC Customs RRD-4C KeyMount Muzzle Device w/ 1/2-28 Threads - RRD-4C-28F-KM
August 2026 on GunPartPicker
JMAC Customs RRD-4C KeyMount Muzzle Device w/ 1/2-28 Threads - RRD-4C-28F-KM ranked #48 of the 143 muzzle devices builders added on GunPartPicker in August 2026. Builders have been adding it to their builds on GunPartPicker since February 2026. All time, it ranks #107 of the 418 muzzle devices builders have added.
Availability is good: it was in stock at one retailer or another nearly every day in August 2026, and today both retailers we track have it in stock. Prices barely moved in August 2026, holding around $121.46, so there haven't been real sales lately. Buying today, the lowest price is $119.99 at Palmetto State Armory, which matches the best price we saw in August.
Updated · from real builds on GunPartPicker · Prices checked · refreshed daily across 35 retailers
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Frequently Built With
The part most often added in each category by the 4 builds that include this one
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Radian Raptor Charging Handle & Talon Safety Selector Combo - OD Green
Strike Industries Ambidextrous Magazine Release, Black - ARAMBIMRBK
Aero Precision M4E1 PRO Stripped Lower Receiver, Ambidextrous Controls - Anodized Black - APAR600030AC
Rosco Manufacturing Bloodline 5.56 AR-15 Barrel Government Carbine - 11.5"
Midwest Industries Quad Rail AR-15 Handguard - 15"
Builds Featuring This Part
See all 1 →Builds in the community that include the JMac Customs RRD-4C KeyMount Muzzle Device w/ 1/2-28 Threads - RRD-4C-28F-KM
| Build | Parts | Total |
|---|---|---|
 | 13 | $1143.87 |
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