Description
20mm XM27 Powered Cupola Spent Brass Chute Door Assembly
The 20mm XM27 Powered Cupola Spent Brass Chute Door Assembly, identified by part number 11605266 and NSN 1005-00-933-1153, is a U.S. Army cartridge-case ejection component for the XM27 powered cupola. The XM27 mounted the M139 20mm cannon on the M114A1E1 armored reconnaissance carrier, later designated M114A2.
The Army parts manual identifies this component as a spent-brass chute door assembly, or weldment. It is the hinged door or flap only, not the complete cartridge-case ejection chute.
Historical Significance
The XM27 powered cupola was part of the Army's effort to give the compact M114 reconnaissance carrier an enclosed, powered 20mm weapon station. Its M139 cannon installation required dedicated ammunition-feed, cartridge-case ejection, and link-ejection hardware within the cupola.
This door assembly represents one small but clearly documented part of that specialized support system. TM 9-1005-307-24P, dated March 1973, places it in Group 6005 with the cartridge-case ejection chute components.
XM27 Cupola and M114A1E1 Relationship
The XM27 powered cupola and M139 20mm cannon were used on the M114A1E1 armored reconnaissance carrier, the model later designated M114A2. The door assembly belongs to the cupola's spent-cartridge-case ejection system rather than to the cannon itself.
What This Item Is and Does
The 20mm XM27 Powered Cupola Spent Brass Chute Door Assembly is the hinged closure shown as item 5 in the Army's exploded view of the cartridge-case ejection chute assembly. It controls the exit opening used by fired 20mm cartridge cases as they leave the cupola's ejection path.
The complete chute assembly also includes a lever, pin, spring pins, chute weldment, and retaining hardware. Those surrounding parts are shown in the manual for context but are not included with this door or flap component.
Key Features
- Item: Spent-brass chute door assembly (weldment)
- Part number: 11605266
- NSN: 1005-00-933-1153
- Application: XM27 powered cupola with M139 20mm cannon
- Vehicle relationship: M114A1E1 armored reconnaissance carrier, later designated M114A2
- Manual reference: TM 9-1005-307-24P, Group 6005, Figure 42, item 5
- Scope: Door or flap component only; complete cartridge-case ejection chute is not included
Why This Item Matters
Few surplus components can be tied to a specific assembly as precisely as this one. The matching NSN, part number, group, figure, and callout establish its place in the XM27 cartridge-case ejection system.
That documentation makes the component useful for a focused XM27 or M114 display, a restoration reference, or technical study of the powered cupola's 20mm installation.
About This Item
The offered item is the 20mm XM27 Powered Cupola Spent Brass Chute Door Assembly, P/N 11605266, NSN 1005-00-933-1153. Only the hinged door or flap is included; this is not the complete spent-brass chute or cartridge-case ejection chute assembly.
The supplied marking 1 EA A-4/77 indicates a quantity of one each. The A-4/77 portion appears consistent with an April 1977 package or inspection notation, but it is not treated as the item's manufacture date.
All items are opened from the original packaging to verify its condition before shipment. If your prefer to receive an item in its original, unopened packaging, please indicate your request in the order comments at checkout. Please Note: If you request an item in its original, unopened packaging, we are unable to verify the item's condition prior to shipment.
Ideal For
This documented XM27 component is well suited for:
- XM27 powered-cupola and M139 cannon-system collections
- M114A1E1 and M114A2 restoration reference
- Military museums and armored-vehicle displays
- U.S. Army ordnance and vehicle-component research
- Film and prop departments seeking an authentic period component
Approx length 10", Approx width 3", Approx height 1", Approx weight lbs.
Pictures are stock images of our inventory. Unless otherwise noted, you will not be receiving the exact item shown in the pictures. The pictures are representative of the item's general condition. The item you receive might be slightly better, or worse, condition than was shown in the pictures.
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