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HK 51000385 UPPER RECEIVER KIT MR556A4 11" 13% Off w/ Free S&H

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HK 51000385 UPPER RECEIVER KIT MR556A4 11
HK 51000385 UPPER RECEIVER KIT MR556A4 11
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HK 51000385 UPPER RECEIVER KIT MR556A4 11

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Questions & Answers
can a Geissele Super Dynamic trigger be compatible with this upper?

Geissele made a trigger specifically for the HK416 / MR556A1 and if I had to guess, that trigger would be fully compatible with the A4 lower receiver. But no, the other triggers will not work. That's why one was made specifically for the MR rifles, big & small caliber

by Keithy baby, Verified Owner, February 17, 2026
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Code: 13-UFH-51000385

MPN: 51000385

UPC: 642230270220

List: $2,499.00Save 13%
$2,179.00

ATTENTION! We currently do not ship this product to AK, CA, HI, IL, NY, WA, P.O. Boxes, and U.S. Territories. Please see our policies for more information.

Product Info for HK 51000385 UPPER RECEIVER KIT MR556A4 11"

HK 51000385 UPPER RECEIVER KIT MR556A4 11" -image

WARNING: California`s Proposition 65

HK 51000385 UPPER RECEIVER KIT MR556A4 11"

HK 51000385 UPPER RECEIVER KIT MR556A4 11" Orderable Models

List of Orderable Models

  • HK 51000385 UPPER RECEIVER KIT MR556A4 11'' , MPN: 51000385 , UPC: 642230270220 , Code: 13-UFH-51000385
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