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NEMO Arms .300 Blackout Custom Carbine Buffer Spring 300BLK-S Color: Black, Fabric/Material: 17-7 Stainless Steel, Includes Blazin' Deal

NEMO Arms .300 Blackout Custom Carbine Buffer Spring, Black, 300BLK-S
NEMO Arms .300 Blackout Custom Carbine Buffer Spring, Black, 300BLK-S
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NEMO Arms .300 Blackout Custom Carbine Buffer Spring, Black, 300BLK-S

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Questions & Answers
Customer Reviews
Helpful Positive Review
well package, smooth spring. by Charles Spencer, Verified Owner, March 9, 2025
Ultra smooth spring, paired with the hydraulic buffer. Makes my blackout operate so smooth between subs and super’s! Just swap mags, no adjustments!
1/2 found this helpful
Helpful Positive Review
Nemo spring by ScubaSteve, Verified Owner, July 23, 2025
Too weak to chamber a round. The H2 buffer is great when paired with a stiffer spring
1/1 found this helpful
Helpful Positive Review
Supressed 300 10.5” barrel by Alex, Verified Owner, September 13, 2025
I have been playing with my AR components to get subsonic ammo to cycle correctly. I have an adjustable gas block and had my gun cycling fairly reliably except no lock back. I was still getting stove pipe jambs if the gun got dirty at all. With this ...
Read More...
4/4 found this helpful
Helpful Positive Review
Nemo arms .300 blackout custom carbine buffer spring by John A, Verified Owner, September 28, 2025
I bought this for my bsf fluted carbonfiber stainless 10" 350 legend build. This spring made it function perfectly!!!! Awesome product
1/1 found this helpful
Helpful Positive Review
Subsonic cycling by LikedItBUT, Verified Owner, April 9, 2025
Wanted my 300BLK to cycle subs without a can. Specifically the 220gr Sabre rounds from AAC. This spring worked Before this spring I tried a bunch of stuff I had and some I borrowed from friends including: Magazines Sprinco "yellow" spring Multipl...
Read More...
5/5 found this helpful
Most Recent Reviews
9” 300 black out suppressed with Kynshot RB5000L by JohnL, Verified Owner, June 24, 2026
My 9” 300 black out with Kynshot RB500L was shooting fine with a Sprinco yellow but wasn’t locking back on the last round. This NEMO Arms spring is a little lighter than the Sprinco yellow and that fixed my problem.
Read All 7 Reviews

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Color:
Black
Fabric/Material:
17-7 Stainless Steel
Gun Make:
AR Platform
Gun Model:
AR-15
Gun Type:
Rifle

Code: 3FR-BUS-AVRE5-300BLK-S

MPN: 300BLK-S

UPC: 866280000402

Blazin' Deal
List: $15.95
$15.15

Product Info for NEMO Arms .300 Blackout Custom Carbine Buffer Spring

NEMO Arms custom .300 Blackout Carbine Buffer Spring. NEMO Arms has engineered a custom carbine buffer spring for carbine length gas systems or troublesome .300 Blackouts that are undergassed. This spring was designed around a rifle with a 16? barrel and a carbine gas system. This spring will also work with other This reduced stiffness buffer spring will allow your .300 Blackout to cycle properly with subsonic ammunition. The spring is made from 17-7 stainless steel that will not corrode and will keep its stiffness and tension longer than standard spring steel.image

Please note that depending upon your gas port size, ammunition, barrel length, suppressor and other factors, you may have to adjust all of these to have your rifle cycle properly.

Specifications for NEMO Arms .300 Blackout Custom Carbine Buffer Spring:

Manufacturer: NEMO Arms
Color: Black
Fabric/Material: 17-7 Stainless Steel
Gun Make: AR Platform
Gun Model: AR-15
Gun Type: Rifle

Package Contents:

  • NEMO Arms .300 Blackout Custom Carbine Buffer Spring

What firearm models does the manufacturer say NEMO Arms .300 Blackout Custom Carbine Buffer Spring is compatible with?

The manufacturer says that NEMO Arms .300 Blackout Custom Carbine Buffer Spring is compatible with AR-15

NEMO Arms .300 Blackout Custom Carbine Buffer Spring Orderable Models

List of Orderable Models

  • NEMO Arms .300 Blackout Custom Carbine Buffer Spring, Black, 300BLK-S , MPN: 300BLK-S , UPC: 866280000402 , Code: 3FR-BUS-AVRE5-300BLK-S
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Last updated 2026-07-28 UTC.