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Guntec USA AR-15 Aluminum Rail Height Gas Block
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DanJM's Review of Guntec USA AR-15 Aluminum Rail Height Gas Block

Bought this over the summer and finally was able to test it out on a couple builds.
Unfortunately, both rifle I tried to used this gas block on experienced weak cycling and repeated failures to eject or feed. The system was just not getting enough gas to cycle properly.
Swapping to different gas blocks fixed these issues, and after un-installing this block I could see very definitive gas blow-by patterns on the barrel and inside the block.
Again this was on two separate builds, experiencing the same problem both times, and the problems going away once switching to a different gas block.

tldr; Poor seal between gas block & barrels, leading to poor reliability.
Pros:
  • Aestetically pleasing
  • Functional rail space
Cons:
  • Unreliable
  • Questionable durability
Would Recommend: No
6 of 6 found the following review helpful.
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