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Riflespeed / Rainier Arms MK1 AR-15 5.56 NATO Upper Receiver Group - 14.5"
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Verified Reviewer

0.0 star rating

07/11/25

Review by Anonymous User

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07/11/25

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Adam U.
Verified Buyer

1.0 star rating

07/11/25

Defective JMAC Threaded Mount – Manufacturing Flaw on First Thread

Review by Adam U. on 11 Jul 2025 review stating Defective JMAC Threaded Mount – Manufacturing Flaw on First Thread
I recently purchased a brand-new JMAC mount from Rainier Arms and ran into a serious issue straight out of the package. When attempting to thread my Resilient RS9 suppressor onto the mount, I immediately noticed significant resistance. My first concern was potential cross-threading or an incorrect thread spec, but after double-checking compatibility and verifying that the threads were properly aligned, the problem persisted.

Upon closer inspection with a pick, I discovered that the resistance was coming from the very first thread. There's a small but clearly visible dent or deformity in that area—deep enough that even after a careful attempt to smooth it out, the defect remains. This is not a burr or damage from improper handling; the mount was installed using proper tools, and the threads were never touched until I attempted to mount the suppressor.

Frankly, I’m extremely disappointed. For a premium product at this price point, JMAC’s quality control should be far better. This kind of defect should never make it out the door.

I’ve reached out to JMAC directly and hope they will stand behind their product and provide a timely resolution—ideally a replacement. I doubt Rainier Arms will assist, as they're just the dealer, but I expect JMAC to take responsibility.

On JMAC Customs 360HD 1/2-28 FaceMount HUB

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07/11/25

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Justin S.
Verified Buyer

5.0 star rating

07/09/25

UN Finally does something right

Review by Justin S. on 9 Jul 2025 review stating UN Finally does something right
Super nice format and layout, great products, good info!

On UN12 Magazine - Issue 18

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07/09/25

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Steven R.
Verified Buyer

5.0 star rating

07/09/25

Loose mag fit on 5. 7 builds

Review by Steven R. on 9 Jul 2025 review stating Loose mag fit on 5. 7 builds
If you build a 5. 7 be prepared for a VERY loose fitting magazine. I cured that with a cut off brass machine screw I threaded into a drilled and tapped hole in the front edge of the mag. Now she's tight. RANIER had the best price and picked up the ball when USPS lost my package (again, bastards), Someone will own a fine custom gun soon. Wish I could post pics.

On Sharps Bros Hellbreaker AR-15 Lower Receiver - Gen 2

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07/09/25

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Beau W.
Verified Buyer

5.0 star rating

07/09/25

A Functional Flash Suppressor

Review by Beau W. on 9 Jul 2025 review stating A Functional Flash Suppressor
You can't even see a flash from the shooter's perspective firing at dusk through a . 357 lever gun. , and it's a rosebud to anyone else. I like it a lot.

On Next Level Armament 9mm Hi-Helix Flash Hider

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07/09/25

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Jason Y.
Verified Buyer

5.0 star rating

07/08/25

18" mod 2 223 wylde ultramatch

Review by Jason Y. on 8 Jul 2025 review stating 18" mod 2 223 wylde ultramatch
Okay so barrel is broken in. This barrel is unbelievably accurate. Printed groups at 100,300,500 today and the verdict is in. WOW! 100 yards 3 shot measured 3/8", 300 yard 3 shot 7/8" and 500 yard measured under 2". Absolutely incredible. More accurate that most big bolt guns.

On Rainier Arms Ultramatch MOD2 .223 Wylde AR-15 Barrel - 18" Nitride

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07/08/25

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Rainier Arms RUC PRO MK1 5.56 NATO Partial Upper Receiver

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