Name: HECKLER AND KOCH (HK USA) MR556A4 UPPER KIT 5.56MM 16.5" - Elk River Guns
Brand: Heckler & Koch / H&K
SKU: RSR|HK51000384
Price: 2330.00 USD
Availability: InStock

Robert Nation

01:19 17 Sep 25

Elk River Guns is a first class outfit. Both knowledgable and attentive. A comfortable place to find your perfect firearm or firearms.!

Michael Stoltz

21:00 16 Sep 25

Great team at Elk River Guns. Took my 20+ year old over/under in for problem with to to barrel not firing. They were able to diagnose and fix the problem quickly. Over the years I have always had a great experience whether buying something new or taking something in for repair. An excellent team that is technically very proficient and personable.

Lucas

22:31 12 Sep 25

Friendly, knowledgeable people. Great to have a shop like this in steamboat!

Peter Chaffee

20:11 31 Aug 25

The best staff, their knowledge is amazing !!! I highly recommend their shop over any shop in the state of colorado !! Thank you to Jae and staff always a pleasure to visit your store!! !!

Stephen Failla

01:23 18 Aug 25

Always a great experience! Pleasure doing business.

tomkitsos

16:35 15 Aug 25

Ben Zvorak

21:40 08 Aug 25

jay hofschulte

20:21 07 Aug 25

Great to work with. Friendly service and very knowledgeable. Glad there here with all the gun rules and regulations in this state.

John Minehan

19:04 30 Jul 25

nakhia pusey

03:27 29 Jul 25

It’s always a joy to go in to Elk River Guns the staff are very helpful friendly and knowledgeable people A+++++++++++++ if you’ve been in more than one time they know you by name so it’s really easy to shop there it feels like home. Thanks guys and keep up the excellent service

Josh Babyak

20:00 26 Jul 25

Best shop best owner best employees ever!!!

Michael Jurgensen

20:22 21 Jul 25

Vance Carlson

21:00 19 Jul 25

Mark M

23:01 03 Jul 25

Great local shop. Knowledgeable staff.

Molly Means

22:49 03 Jul 25

They did a great job

Ricardo Galvan

02:23 03 Jul 25

Really friendly and knowledgeable a great place to go look for a new firearm 100% recommended

Elk Archer

23:32 30 Jun 25

I think they are the friendliest and most knowledgeable gun shop in Northwest Colorado. Really great spot.

Vincent Drogosz

14:56 20 Jun 25

Knowledgeable sales staff and great selection of guns, ammo, and accessories.

jay hofschulte

02:25 17 Jun 25

Joyce Treulieb

22:34 05 Jun 25

Amazing!

Michael Kusy

20:21 03 Jun 25

Always a great experience at Elk River Guns!

Jeff Von Almen

22:21 20 May 25

David was great!

Jarrod Raper

21:38 19 May 25

Staff helps with every step of the process and make sure you know what is going on! They are super informative. Great people.

Timothy Moorehead

19:56 17 May 25

Great gun shop with good selection and better service.
I have found a new favorite!

Stephen Failla

16:56 13 May 25

Dan Emert

15:20 12 May 25

These folks run an impressive operation and are great at everything they do. Highly, highly recommend.

Joel Harris

22:07 09 May 25

Friendly helpful & very well informed. Competitive pricing.

David Smith

17:30 07 May 25

Just got another brick of Hornady 17 HMR 15.5 gr. NTX. It gives exceptional accuracy at 100 yards, is devastatingly lethal on ground squirrels, and doesn’t poison the raptors.

DAVE MIHAICH

19:31 04 May 25

Always a pleasure at Elk River Guns!!👍🏻

Dakota Thvedt

11:02 03 May 25

Alan Clemens

23:02 02 May 25

Great and friendly service as always!

Eric Edelstein

22:33 17 Apr 25

Danny Hulslander

23:13 15 Apr 25

I've had nothing but good experiences with these guys!! Whether it's buying a new firearm, getting some gunsmithing done or selling/trading in a used firearm, they make it an easy and welcoming experience! Thanks guys!

Bob Forster

19:40 09 Apr 25

Great service. Jae made some great recommendations. Very happy with resuling product purchased.

Kasen Brennise

18:13 08 Apr 25

lawrence Belton

13:37 01 Apr 25

Heath Scroggs

00:19 27 Mar 25

Everyone was really excited to help one out!! An amazing environment!!

Mikey DeRock

22:40 25 Mar 25

Everything in house seems to be awesome, staff is friendly and helpful, you could sit and talk to everyone for far too long!

Waited a bit too long getting a barrel threaded, but that is not done in house and by a sub contractor.

Everything in house from customer service to selection was wonderful, I will be bringing my buisness back again!

Frances Jenkins

01:34 19 Mar 25

Very friendly and extremely knowledgeable staff.

Juan Landa

18:02 10 Mar 25

Wonderful service and great people!

Ron Mentch

22:33 07 Mar 25

Very friendly and helpful!

Sharon Cantu

00:17 02 Mar 25

Friendly & kind , Great customer services . Took the time to explain their products to me . Recommend for everyone to go check them out. Thank you for all your help .

Dave Chapin

21:51 28 Feb 25

As always, great service, very happy with my purchase. Definitely my go to store for anything gun related. Thanks elk river!

Jeff Jewson

04:39 28 Feb 25

Cannon Balls

23:23 27 Feb 25

Best store in town. Knowledgeable Smart people. Best store in Colorado as far as I know.

Donna Segale

22:14 22 Feb 25

I needed to get rid of these guns my husband had that I discovered after he passed. I am not used to being around guns and a bit nervous around them. Everyone at the store were very nice and gave me a fair price for them. The 2 dogs were also sweet.
I would highly recommend them.

Scott Baraw

04:06 22 Feb 25

Elk River Guns is like family! They are knowledgeable and understanding for all your gun related needs. Jae the owner is willing to go the extra mile to make sure you are happy with your purchase/future purchases. Dave has impeccable memory. He remembers everyone’s name and welcomes you by name with a warm smile when you walk through the door. Other shops employees just want to take your money any way how. These guys are there to make your day better. They are my number one gun store in my books.Best in the northwest!

Chris H

23:22 13 Feb 25

Jae and Elk River was my go to FFL before I moved away from Steamboat. Just bought a few products from them even though I now live across the country. Elk River was responsive, shipped my product quickly in a well packaged box. Transaction was seamless. Will continue to do business with Jae and Elk River Guns.

Ralph Torres

23:09 12 Feb 25

Very knowledgeable employees in this store ifthey don’t have it. They will order it for you. I’ve never had a bad experience with elk River guns

C Young

07:55 24 Oct 24

Can’t recommend them enough. A lot of gun shops have shady salesman or condescending staff, and it’s the opposite here. David (Mr. Smith) is just the most welcoming warm person to have greet you and guide you through any of your needs. He’s downright hilarious too! Jae is the wizard you can trust with all your gunsmithing needs and is obviously effortlessly knowledgeable with any and everything guns. He has both fixed my broken handgun and mounted an optic within 10 minutes of walking in the store while charging a very fair price. Just crazy levels of service that’s so rare nowadays. Tip this man he deserves it. They have a great selection of guns/parts and transfers, though on the expensive side for transfers, (you’re in steamboat, don’t be unrealistic), are a breeze. In small towns like this we are lucky to have shop of this caliber (pun intended).

UPC	642230270213
Manufacturer	Heckler & Koch / H&K
Manufacturer Part Number	51000384
Length	43.9500
Caliber/Gauge	.223 REM/5.56 NATO
Barrel Length	16.5
Barrel Finish	STAINLESS
Model	MR556 A4 Upper Receiver
Product Type	Upper
Shipping Weight	11.3
Package Height	3.5
Package Width	13.5
Rate of Twist	1-in-7"

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HECKLER AND KOCH (HK USA) MR556A4 UPPER KIT 5.56MM 16.5″

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