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MR556 spare parts

Walker77

Joined: Sep 2006

Posts: 1032

EE: 100% (3)

MO, USA

Posted: 6/21/2026 7:20:47 PM EDT

Picked up a new MR556A4 a month ago. I always like to keep spare parts on hand. What should I get for this rifle and where's the best place to get them?

So far on the list I have a bolt and firing pin.

How is the quality of the BRN-4 parts?

Uys

Joined: Jun 2006

Posts: 677

EE: 0% (0)

USA

Posted: 6/22/2026 12:52:26 AM EDT

[Last Edit: Uys][Edited] [#1]

MGW, PAI, Blue Ridge Supply and Hk USA are my go-to. Have not tried Brownells parts.

AR18

Joined: Jun 2001

Posts: 24289

EE: 100% (48)

FL, USA

Posted: 6/26/2026 8:28:02 PM EDT

[#2]

Quote History

Originally Posted By Uys:
MGW, PAI, Blue Ridge Supply and Hk USA are my go-to. Have not tried Brownells parts.

View Quote

I have used the Brownell BRN-4 parts and they are pretty much interchangeable .

Black-Tiger

Member

Joined: Jan 2006

Posts: 34000

EE: 100% (17)

TX, USA

Posted: 8/4/2026 12:49:20 PM EDT

[#3]

Just my .2

I would go over to Gatewood Supply, RTG or even HKP (you'll pay more here) and get spare there.

triode

Member

Joined: Mar 2010

Posts: 3626

EE: 100% (9)

USA

Posted: 8/4/2026 1:03:56 PM EDT

[#4]

Quote History

Originally Posted By Black-Tiger:
Just my .2

I would go over to Gatewood Supply, RTG or even HKP (you'll pay more here) and get spare there.

View Quote

HKP tends to have the most inventory and more items in stock. A tradeoff for being a more expensive in some cases.

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MR556 spare parts

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MR556 spare parts