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What size to replace an a2 sight? — 1 Answer

by Clayton, from NE, United States Asked on November 12, 2021

Name Spikes Tactical ST Micro Rifle Gas Block (4.9)
$47.46 $29.99 Save Up to 38%
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Answered by Ethan, Gear Expert, from IL, United States, on March 11, 2022

Most AR15 rifles and pistols that utilize a fixed front sight gas block use a .750" gas journal. However, it is not always the case. More than likely you would need the .750" Spikes Tactical ST Micro Rifle Gas Block, but I would still recommend emailing us at Techsales@opticsplanet.com and letting us know what specific rifle/pistol you have. That way we can confirm the exact size of your gas journal.

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