Originally Posted By dotcombust:
Couple of questions.
Are these endomag inserts?
I'm currently running a blowback 9mm pcc but I'm looking to buy a CMMG RDB barrel and bcg kit.
Are the ARC mags compatible with blowback bolts as well as the RDB?
I'd rather have one type of 9mm inserted mag rather than 2.
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No, see my last post on this thread:
https://www.ar15.com/forums/Armory/WTK-Current-AR15-9mm-Options-/48-492376/
The Guard relies on the ejector IN the bolt just like how a standard 556 bolt works. You can order Endomags with the ejector cut off or do it yourself and so all those ejector issues are not a problem with the Guard setup. Picture below shows Guard endomag direct from MEAN arms where they removed the ejector. Bottom is the Endomag that still has the ejector.
Note the picture above is old. The top Endomag insert for the CMMG RDB has been updated to a new 'gen2' version.
Picture below shows newer version on the right that has a more conical feed ramp as well as 'wings' that go over the rounds to prevent them from jumping up and hitting high on the barrel extension.