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what size gas block and length gas system do I need for the 20" .308 super sniper barrel? — 3 Answers

by MrMHM, from MI, United States Asked on March 14, 2021

Name Wilson Combat AR Threaded Barrel (4.6)
As Low As $243.49 Save Up to 18%
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A
Answered by Patrick, Gear Expert, from IL, United States, on August 31, 2021

The gas tube length you will need will be a mid length gas tube.

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A
Answered by Gary, member, from PA, United States, on November 26, 2021

The Wilson 20" 308 caliber barrel will require the Wilson 15.5" rifle gas tube.
Not the standard rifle gas tube which is 15.125" commonly used with other manufactures.
The 15.5" gas tube will not work with standard rifles either. It will not allow the BCG to fully engage.
Gas block size is 0.875"

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Answered by Paladin, member, from WA, United States, on November 12, 2021

The gas block required is a .875" and the required gas tube is a rifle length.

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Last updated 2025-11-12 UTC.