Custom AR9 - switch to CMMG's radial delayed blowback BCG

[Billy55444]

I have a traditional AR9 build with a direct blowback set up. I am using a Spikes Tactical dedicated glock lower. I am interested in switching over to CMMG'S radial delayed blowback BCG and barrel. The issue is, I believe the fixed ejector in this lower will not work with CMMG's RDB BCG. Would removing the fixed ejector solve my problem? I want to avoid having to buy CMMG'S dedicated glock lower that was designed for their RDB BCG. Sorry for the noob question - still new to the AR world.

Thanks,
Billy

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[arrowshooter]

Welcome Billy. From the CMMG website if this s the setup you are talking about:

Our MkG Barrel and Bolt Kits are designed to work exclusively with our MkG Lowers, and a mil-spec upper receiver with enlarged ejection port. Other manufacturers' receivers may work, but we cannot guarantee function or reliability. For more information regarding fitment, check with our Tech Support team.

 

[rdtompki]

If you have any AR15 lowers you can simply use the Mean Arms Endomag Pmag inserts specific to CMMG uppers.You will need the CMMG barrel along with the BCG. This is a very soft shooting setup with a normal carbine buffer. If you're going to run various bullet weights with and without a suppressor I'd recommend an A5 buffer tube/Kynshot RB5007 buffer/Tubbs flat wire 553 buffer spring (see @Amphibian's excellent work over at AR15.com). This buffer works with every riffle/bullet combination I've tried and is even softer shooting than the stock RDB setup.