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Reviews & Ratings for NEMO Arms .300 Blackout Custom Carbine Buffer Spring — 5 reviews

(5 reviews)
NEMO Arms .300 Blackout Custom Carbine Buffer Spring
NEMO Arms .300 Blackout Custom Carbine Buffer Spring
$29.49 $25.99 Save 12%
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Most Helpful Positive Review Subsonic cycling
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 Multiple carbine springs Various buffer weight / spring combos (from "empty", to h4 and many between) Low-Mass BCG Gas block(s) and tubes Dripping in oil Drilling out the gas port Also tried the upper on multiple lowers including ones with low-power hammer springs, drop in triggers, etc. No combination of the above made it cycle reliably. Installe...
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Nemo arms .300 blackout custom carbine buffer spring

by John A, Verified Owner from MI, United States Written on September 28, 2025
I bought this for my bsf fluted carbonfiber stainless 10" 350 legend build. This spring made it function perfectly!!!! Awesome product
Pros:
  • Made my custom 350 legend build work
Cons:
  • price
Best Used for:
  • 300blk or 350 legend
Would recommend: Yes
Was it helpful to you? Yes | No
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Supressed 300 10.5” barrel

by Alex, Verified Owner from OK, United States Written on 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 spring and an H3 weight I was able to adjust the gas block and get great cycling reliability and full lock back.
Pros:
  • Works great and as advertised
Cons:
  • None
Would recommend: Yes
1 of 1 found the following review helpful.
Was it helpful to you? Yes | No
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Nemo spring

by ScubaSteve, Verified Owner from TX, United States Written on July 23, 2025
Too weak to chamber a round. The H2 buffer is great when paired with a stiffer spring
Would recommend: No
Was it helpful to you? Yes | No
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well package, smooth spring.

by Charles Spencer, Verified Owner from NC, United States Written on 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!
Would recommend: Yes
0 of 1 found the following review helpful.
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