SOTA Arms AR-15 Big Bore Assembled Upper Receiver - Large Bore Port - Billet Aluminum
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6 Magazines Per Order: Due to extreme volume, we are limiting sales of magazines to 6 per customer order. This applies to individual and bundled magazines. AT3 reserves the right to cancel any order over the 6 magazine limit.
Product description
Assembled AR-15 Upper with Extra Room for Large Cartridge Cases
Features
- AR-15 upper receiver can be used with standard AR-15 cartridges when paired with the correct caliber-specific components
- Extra-wide ejection port provides additional clearance for larger cartridge cases
- Well suited for .458 SOCOM, .450 Bushmaster, .50 Beowulf / 12.7×42, .375 SOCOM, and .358 SOCOM builds
- Also provides additional ejection clearance for 400 Legend builds
- CNC-machined billet aluminum construction
- Flat-top configuration with M4-style feed ramps
- Dust cover and forward assist components already installed
- Type 3 black hardcoat anodized finish
- Made in the USA
The SOTA Arms Big Bore Assembled Upper remains an AR-15-pattern receiver and can be used with conventional AR-15 cartridges when the rest of the upper is configured for the intended caliber. The oversized ejection window is primarily useful with cartridges such as .458 SOCOM, .450 Bushmaster, .50 Beowulf / 12.7×42, .375 SOCOM, and .358 SOCOM, where the larger case dimensions can require more clearance than a standard AR-15 port provides. It also gives a 400 Legend build additional room for ejection, although 400 Legend can generally operate with a standard-size AR-15 ejection port. This assembled version adds the dust cover and forward assist components, reducing the number of receiver parts needed to finish the upper.
Note: The enlarged ejection port alone does not convert an AR-15 to a big-bore cartridge. Use the correct barrel, bolt, magazine, gas-system components, and other caliber-specific parts for the intended build.
Specifications
- Brand: SOTA Arms
- Model: Big Bore Assembled Upper Receiver
- MPN: A-605-1
- Construction: CNC-Machined Billet Aluminum
- Configuration: Assembled, Flat Top
- Feed Ramps: M4 Style
- Ejection Port: Extra Wide for Big-Bore AR-15 Cartridges
- Finish: Type 3 Hardcoat Anodized
- Color: Black
- Country of Manufacture: USA
What’s Included
- 1x SOTA Arms AR-15 Big Bore Upper Receiver
- 1x Dust Cover Door
- 1x Dust Cover Rod
- 1x Dust Cover Spring
- 1x Forward Assist Assembly
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Warranty & returns
90-day no-hassle returns
The AT3 Tactical store has a 90 day no-hassle return policy for products in good condition. You can view the full details of our return policy here.
If you encounter an issue or defect with a product after 90 days of your purchase, you can refer to the manufacturer for a warranty claim. Their policies are below.