Does the CMMG MK4 .223 Remington AR Lower work with the CMMG MK4 .300BLK Banshee Upper Group?
Lower Receiver
CMMG MK4 .223 Remington AR Lower
from $100.02
Upper Receiver
CMMG MK4 .300BLK Banshee Upper Group Receiver 12.5in
from $799.99
CMMG lower and CMMG upper compatibility
Yes, they fit
The CMMG MK4 .223 Remington AR Lower works with the CMMG MK4 .300BLK Banshee Upper Group Receiver. Our compatibility rules found no conflict between them.
No one has built this exact setup yet, but CMMG lowers with CMMG uppers are a common pairing.
Counted from real GunPartPicker builds: parts lists people put together while planning to buy.
Checked by the same rules the AR builder runs on every part you add: caliber, frame size, receiver pattern, thread pitch and gas length.
Fit is judged from the specs retailers list, which can be missing or wrong. Confirm with the manufacturer before you buy, and have a qualified gunsmith check any build before you fire it.
How often builders pair the CMMG lower and CMMG upper
Backed by tens of thousands of qualified builds that have both a lower and an upper.
Share of builds with the CMMG MK4 .223 Remington AR Lower and any upper
CMMG MK4 .223 Remington AR Lower
- Of lower picks
- 0.3%
- Median paid
- $99
CMMG MK4 .300BLK Banshee Upper Group
Not in enough builds yet to report.
How we count ⌄
These shares come from GunPartPicker's build data: real parts lists people put together while planning a purchase, not sales or surveys. A build counts a part only when it is the final pick for its slot, so parts that were swapped out never count. Fit never comes from these numbers; it comes from our compatibility rules alone.
Frequently built with the CMMG lower and CMMG upper
The part builders pick most often in each slot alongside these two, checked against both. Parts that conflict are left out.
Bolt Carrier Group
Fits both
Stock & Brace
Trigger
Charging Handle
Pistol Grip
Gas Block
Handguard
TacFire Maximize Your 's Potential
Fits both
Barrel
FN America FN 16 Mid-Length 5.56mm
Fits both
CMMG MK4 .223 Remington AR vs CMMG MK4 .300BLK Banshee Upper: specs and prices
| CMMG MK4 .223 Remington AR | CMMG MK4 .300BLK Banshee | |
|---|---|---|
| Best price | $100.02 at Classic Firearms | $799.99 at Optics Planet |
| Stores | 3 of 7 in stock | 0 of 1 in stock |
| Assembly | Stripped | Complete |
| Platform | AR-15 | AR-15 |
| Caliber | 5.56 NATO | 300 Blackout |
| Finish | Cerakote | n/a |
| Color | Black | n/a |
| Length | n/a | 12.5 |
Both for $900.01 at today's best prices.
Today's best prices and 90 day price history
Every store we track for each part, cheapest in stock first. Prices are checked through the day.
Price history, last 90 days
- CMMG MK4 .223 Remington AR Lower: lowest $94.69 on Jul 15, highest $126.99 on Jul 11 over the last 90 days.
- CMMG MK4 .300BLK Banshee Upper Group: lowest $799.99 on Jul 5, highest $799.99 on Jul 5 over the last 90 days.
Upper Receivers frequently paired with the CMMG MK4 .223 Remington AR Lower
Most picked next to it in real builds. Only parts our rules say fit the CMMG MK4 .223 Remington AR Lower are listed.
Lower Receivers most paired with CMMG uppers
The CMMG MK4 .300BLK Banshee Upper Group is not in enough builds yet, so these are the most picked next to any CMMG upper. Only parts our rules say fit the CMMG MK4 .300BLK Banshee Upper Group are listed.
