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Complete Upper Receivers

Complete Upper Receivers

Daniel Defense MK18 RIII Complete Upper Receiver - 10.3" Black

$1,366.00
As low as $99.29/mo with . Learn More

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Geissele URG-I Near Clone 5.56 NATO Complete Upper Receiver Group - 10.3"
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Verified Reviewer

0.0 star rating

06/17/25

Review by Anonymous User

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06/17/25

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Jordan H.
Verified Buyer

5.0 star rating

06/17/25

Cut & thread/upper disassembly

Review by Jordan H. on 17 Jun 2025 review stating Cut & thread/upper disassembly
Rainier did great work disassembling my pinned upper. They also cut and thread the barrel to move to a new pistol build and everything went great with quality workmanship. I would have them do any future needed gunsmithing.

On Cut & Threading

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06/17/25

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James
Verified Buyer

5.0 star rating

06/16/25

Best Budget Lower Receiver

Review by James on 16 Jun 2025 review stating Best Budget Lower Receiver
Ordered again, this time 3. It's just that good. Perfect tolerances, Milspec to the core. I built 6 with this lower and so far it just runs flawless. Talk about High Quality Budget builds, this is the one! Will buy more in the future! Also Rainier Arms is the best, just wish they can overstock on a lot of items.

On Airborne Arms AAM4 AR-15 Stripped Lower Receiver

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06/16/25

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Chris A.
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5.0 star rating

06/11/25

Top 1X Prism

Review by Chris A. on 11 Jun 2025 review stating Top 1X Prism
For the money you pay, you wont beat this beast. Crystal clear, large sight picture, and holds zero reeeaaalll nice. As long as you aren’t a potato, you’ll hit everything you aim at with it within 100yards, and I was constantly on steel (12in x 12in) with it at 200yards.

Lifetime warranty? Are you kidding?

Just run this, and thank me later.

Also, Rainer Arms, can’t go wrong with this great company.

On Atibal P1 Solar 1x Motion Activated Micro Prism Optic

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06/11/25

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Kevin A.
Verified Buyer

5.0 star rating

06/07/25

Barrel nut.

Review by Kevin A. on 7 Jun 2025 review stating Barrel nut.
Looks good works great

On V Seven Weapon Systems Titanium GI Barrel Nut

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06/07/25

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Mic N.
Verified Buyer

5.0 star rating

06/05/25

Perfect

Review by Mic N. on 5 Jun 2025 review stating Perfect
Best investment for magazine made to my AR

On Driven Arms Co. AR15 Standard Forged Slip Fit Magwell

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06/05/25

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$1,479.00
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