
Availability: In Stock
The CMMG FourSix 30-round polymer magazine is the standard feeding solution for the CMMG Mk4 AR-15 platform chambered in 4.6x30mm. Built from durable polymer construction, this magazine holds a full 30 rounds and is engineered to handle the ballistics and feeding geometry of CMMG's proprietary intermediate cartridge. If you're running a modern AR-pattern rifle in this caliber, a reliable magazine is as critical as your barrel—this one does the job without fuss.
CMMG designed this magazine specifically for the Mk4 platform, so compatibility is straightforward. The 4.6x30mm round sits in a different velocity and trajectory window than 5.56 or .300 Blackout, which means magazine design matters. This 30-round capacity gives you solid trigger time between reloads on the range or in the field, whether you're testing accuracy, running drills, or working up loads.
The black polymer construction keeps weight down and resists corrosion, making it a practical choice for hunters, shooters, and tinkerers who want dependable, no-frills ammunition storage. Whether you're building out your Mk4 rifle with a full magazine loadout or replacing worn or lost mags, having multiple reliable sources of supply removes one variable from your shooting equation.
| Caliber | 4.6x30mm |
| Capacity | 30 rounds |
| Material | Polymer |
| Color | Black |
| Platform Compatibility | CMMG Mk4 AR-15 |
This magazine is designed for the CMMG Mk4 AR-15 platform in 4.6x30mm. The 4.6x30mm cartridge is specific to CMMG's platform, and this magazine is engineered for that round. Compatibility with other AR variants or calibers is not supported.
The CMMG FourSix magazine holds 30 rounds of 4.6x30mm ammunition.
This magazine is constructed from polymer, which offers corrosion resistance and lighter weight compared to steel.

SKU: 115808124 • Weight: 1oz
Availability: In Stock
The CMMG FourSix 30-round polymer magazine is the standard feeding solution for the CMMG Mk4 AR-15 platform chambered in 4.6x30mm. Built from durable polymer construction, this magazine holds a full 30 rounds and is engineered to handle the ballistics and feeding geometry of CMMG's proprietary intermediate cartridge. If you're running a modern AR-pattern rifle in this caliber, a reliable magazine is as critical as your barrel—this one does the job without fuss.
CMMG designed this magazine specifically for the Mk4 platform, so compatibility is straightforward. The 4.6x30mm round sits in a different velocity and trajectory window than 5.56 or .300 Blackout, which means magazine design matters. This 30-round capacity gives you solid trigger time between reloads on the range or in the field, whether you're testing accuracy, running drills, or working up loads.
The black polymer construction keeps weight down and resists corrosion, making it a practical choice for hunters, shooters, and tinkerers who want dependable, no-frills ammunition storage. Whether you're building out your Mk4 rifle with a full magazine loadout or replacing worn or lost mags, having multiple reliable sources of supply removes one variable from your shooting equation.
| Caliber | 4.6x30mm |
| Capacity | 30 rounds |
| Material | Polymer |
| Color | Black |
| Platform Compatibility | CMMG Mk4 AR-15 |
This magazine is designed for the CMMG Mk4 AR-15 platform in 4.6x30mm. The 4.6x30mm cartridge is specific to CMMG's platform, and this magazine is engineered for that round. Compatibility with other AR variants or calibers is not supported.
The CMMG FourSix magazine holds 30 rounds of 4.6x30mm ammunition.
This magazine is constructed from polymer, which offers corrosion resistance and lighter weight compared to steel.
SKU: 115808124 • Weight: 1oz
