Aero Precision Assembled XL Upper Receiver for Big Bore AR-15 - Enlarged Ejection Port - (DISCONTINUED)
or 4 interest-free payments of $33.75 with
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.
Frequently bought together
From orders that included this itemProduct description
AR-15 Upper for Big Bore Calibers – .450 Bushmaster, .458 SOCOM, .50 Beowulf
If you’re planning a big bore build for your AR-15, one area that often goes overlooked is the upper. The brass from .450 Bushmaster, .458 SOCOM, or .50 Beowulf, won’t fit through a standard AR-15 upper’s ejection port. Luckily, Aero Precision makes a forged upper receiver that solves this issue, with a port door sized for larger brass casings.
The XL Upper is just like your standard forged upper, with two key differences. One, the enlarged ejection port opening, plus a laser-engraved “XL” on the rear tang. Just to make it easy to distinguish from your other upper receivers.

Forged From 7075-T6 Aluminum
Just like the other Aero uppers you can trust, the XL is Type III Class 2 hard coat anodized or finished with Magpul FDE Cerakote. The 7075-T6 aluminum forgings are completely within spec in every other way, ensuring compatibility with other dust covers, forward assists, handguards and more. The only real difference is the ejection port opening, and the distinguishing “XL” on the tang.
Features:
- Port door opening enlarged to enhance larger diameter brass ejection (.450 Bushmaster, .458 SOCOM, .50 Beowulf, etc.)
- Features Laser Marked “XL” designation on the upper receiver tang
- Compatible with AR15 Lower receivers
- Compatible with AR15 Port Doors and Forward Assists
- .250 takedown pin holes
- Includes port door and forward assist
Specifications:
- PLATFORM: AR15
- MATERIAL: Machined from 7075-T6 forged aluminum
- FINISH: Anodized Black or FDE Cerakote
- COMPATIBILITY: Works with all Mil-spec AR15/M16 components
- ENHANCEMENTS: Enlarged ejection port for big bore brass
- WEIGHT: 8.35oz
All 2 options on this page
Customer reviews 1
AT3 Tactical · Thanks for sharing your feedback! We're glad you're satisfied with your purchase.
Questions & Answers
No questions yet. Ask about fit, install or compatibility and our team answers within a business day.
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.






