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Q&A for Stern Defense SD 8.5in MOD5 MLOK .40SW Upper Receiver Assembly — 3 Questions & 1 Answers

Name Stern Defense SD 8.5in MOD5 MLOK .40SW Upper Receiver Assembly
$555.12 $535.00 Save $20.12
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Q
Dmac, member, from TN, United States, asked on October 08, 2024

What weight buffer is recommended for this upper?

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A
Answered by STERN DEFENSE, Manufacturer from MO, United States, on November 27, 2024

We recommend not going lighter than 7.5 oz. We also have a 11oz buffer that works great with .40SW

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Q
Steven Castle, member, from FL, United States, asked on July 12, 2026

will this upper work on an ar9 lower?

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Q
Justin, guest, from OK, United States, asked on December 03, 2025

Will this work on the Aero EPC-9 lower?

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Last updated 2025-11-12 UTC.