JavaScript seems to be disabled in your browser. For the best experience on our site, be sure to turn on Javascript in your browser.

Rainier Arms

Pursue Your Passion

Menu

Account

Home
Rifle Parts

Rifle Parts

Whether you're building a new rifle from scratch or looking to upgrade an existing firearm, our vast selection of rifle parts has everything you are going to need in that journey. At Rainier Arms' selection of rifle parts, you can find a wide variety of products including lower and upper parts, trigger parts, muzzle devices, and many more.

Explore our selection of high-quality parts coming from various leading manufacturers like Strike Industries, Magpul, BCM, and many more.

Also, don't forget to check our specially-made Rainier Arms barrels for your firearms.

Rainier Arms RUC PRO MK1 5.56 NATO Partial Upper Receiver - 12.5"
★ Reviews

Popup content starts

Reviews by

close Popup

These are real reviews
from real shoppers

4.8 star rating 30639 Reviews

Site Reviews

Product Reviews

WRITE A REVIEW

* Indicates a required field

* Score:

* Title:

* Review:

You are connected as

Connect with:

-OR-

* Use your name:

* Email:

Review's title & body can't be empty Question's body can't be empty Please enter a star rating for this review Name field cannot be empty Invalid email Your review has already been submitted. Max length was exceeded Please fill out all of the mandatory (*) fields One or more of your answers does not meet the required criteria

Thank you for posting a review!

We value your input. Share your review so everyone else can enjoy it too.

share

share

share

Thank you for posting a review!

Your review was sent successfully and is now waiting for our staff to publish it.

Verified Reviewer

0.0 star rating

07/07/25

Review by Anonymous User

On

share ' Share Review by Anonymous User facebook facebook Share Review by Anonymous User twitter twitter Share Review by Anonymous User LinkedIn linkedin Share Review by Anonymous User

07/07/25

Was this review helpful?

0

0

R
Ricky B.
Verified Reviewer

5.0 star rating

07/06/25

Great barrel at a great price!

Review by Ricky B. on 6 Jul 2025 review stating Great barrel at a great price!
Don't be nervous to pull the trigger on this barrel. I've got over 1000 rounds of ammo through my 18" ultramatch fluted. It prints sub 1" MOA groups consistently when fed with at least 62gr NATO. With 77gr (particularly 77gr SMK bullets) you can get closer to sub . 5" MOA. Barrel is about as light as a rifle length barrel gets while retaining this type of rigidity and resonance period (yes including proof research / other boutique barrels. I noticed that cold bore shots vs a warm gun had a smaller deviation than that of other 16" / 18" barrels that I have shot with. Bottom line, if you're building an accurized ar15, this will meet or beat your expectations.

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

share ' Share Review by Ricky B. on 6 Jul 2025 facebook facebook Share Review by Ricky B. on 6 Jul 2025 twitter twitter Share Review by Ricky B. on 6 Jul 2025 LinkedIn linkedin Share Review by Ricky B. on 6 Jul 2025

07/06/25

Was this review helpful?

0

0

M
Mike p.
Verified Buyer

5.0 star rating

07/06/25

Looks good works well

Review by Mike p. on 6 Jul 2025 review stating Looks good works well
Seems to help with rise and recoil. Shoots much better than with just a flash supressor. Wish it had threads for a can on the outside, but two out of three ain't bad. Also priced well.

On Rainier Arms Xtreme Tactical Compensator (XTC) 2.0 .308/7.62 Muzzle Device - Black Nitride

share ' Share Review by Mike p. on 6 Jul 2025 facebook facebook Share Review by Mike p. on 6 Jul 2025 twitter twitter Share Review by Mike p. on 6 Jul 2025 LinkedIn linkedin Share Review by Mike p. on 6 Jul 2025

07/06/25

Was this review helpful?

0

0

J
James C.
Verified Buyer

5.0 star rating

07/05/25

Rainier Arms is Number 1

Review by James C. on 5 Jul 2025 review stating Rainier Arms is Number 1
Great Product. Great Service and fast shipping at a great price.

On KNS Precision .154 Non-Rotate Trigger / Hammer Pin MOD ST

share ' Share Review by James C. on 5 Jul 2025 facebook facebook Share Review by James C. on 5 Jul 2025 twitter twitter Share Review by James C. on 5 Jul 2025 LinkedIn linkedin Share Review by James C. on 5 Jul 2025

07/05/25

Was this review helpful?

0

0

D
David P.
Verified Buyer

5.0 star rating

07/04/25

choosing the best!

Review by David P. on 4 Jul 2025 review stating choosing the best!
I have two of the Maxim Defense CQB in black I've met the owner & several people that work at Maxim, all of there products are top notch. Great stock & great pricing from Rainier Arms Thank you!

On Maxim Defense CQB Gen 7 Stock for AR-15 - FDE

share ' Share Review by David P. on 4 Jul 2025 facebook facebook Share Review by David P. on 4 Jul 2025 twitter twitter Share Review by David P. on 4 Jul 2025 LinkedIn linkedin Share Review by David P. on 4 Jul 2025

07/04/25

Was this review helpful?

0

0

J
Jonathan K.
Verified Buyer

5.0 star rating

07/02/25

Great product

Review by Jonathan K. on 2 Jul 2025 review stating Great product
Fit perfectly on my Mac 5. No complaints.

On Lee Sporting Aluminum MP5 / SP5 / HK Clone Lower Housing - Full-Size Push-Pin

share ' Share Review by Jonathan K. on 2 Jul 2025 facebook facebook Share Review by Jonathan K. on 2 Jul 2025 twitter twitter Share Review by Jonathan K. on 2 Jul 2025 LinkedIn linkedin Share Review by Jonathan K. on 2 Jul 2025

07/02/25

Was this review helpful?

0

0

1 2 3 4 5 6 7 8 9

Reviews by

Popup content ends
Out of stock

Add to Wish List Add to Compare

notify me

Now Shopping by

Threaded No Remove This Item
Thread Pitch 1/2x28 (.22 cal) Remove This Item

Clear All

Shopping Options

My Wish List

Last Added Items

You have no items in your wish list.

Google Customer Reviews

Google Customer Reviews