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Rainier Arms

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Receiver Parts

Rainier Arms RUC PRO MK1 5.56 NATO Partial Upper Receiver
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4.8 star rating 30370 Reviews

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Verified Reviewer

0.0 star rating

04/03/25

Review by Anonymous User

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04/03/25

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MICHAEL V.
Verified Buyer

5.0 star rating

04/02/25

Great grips

Review by MICHAEL V. on 2 Apr 2025 review stating Great grips
Love it. Put it on my DDM4. I put a different Driven arms grip on my rattler. Both are my top grips

On Driven Arms Co. Utility Compact Grip (ULCG Gen 2) - Atom

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04/02/25

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Henry H.
Verified Buyer

5.0 star rating

04/02/25

I'd say buy them all, but

Review by Henry H. on 2 Apr 2025 review stating I'd say buy them all, but
then there wouldn't be any left for me. I've got about 23 of these. Fantastic mags, great in the hand, slim profile, feed reliably and CHEAP!! at rainier.

On Hera Arms H3T Polymer Magazine - 30 Round Black (10 Pack)

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04/02/25

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Ethan B.
Verified Buyer

5.0 star rating

04/02/25

WORTH IT

Review by Ethan B. on 2 Apr 2025 review stating WORTH IT
High quality and cleans up the charging action compared to the OEM plastic piece.

On HB Industries Grand Power Stribog SP9A3 Locking Charging Block

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04/02/25

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Johnnie L.
Verified Buyer

5.0 star rating

04/02/25

Rainier Arms & Red Dirt Top Notch

Review by Johnnie L. on 2 Apr 2025 review stating Rainier Arms & Red Dirt Top Notch
AWESOME trigger and fast shipping!!! Thanks!!!

On Red Dirt USA ST Prodigy Flat Adjustable Aluminum Trigger - F4

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04/02/25

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David E.
Verified Buyer

5.0 star rating

04/02/25

Fast Service, Great Product, looking

Review by David E. on 2 Apr 2025 review stating Fast Service, Great Product, looking
Fast Service, Great Product, looking forward to future orders with Rainier Arms

On Holosun Solar Charging Sight RMSc - Green

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04/02/25

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