This video Documented the process of getting a CMMG RDB BCG and Barrel combination to work in an Aero EPC 9. Step #2 and #4 are the hardest parts. Go Slowly in the process. PLEASE NOTE – This does not instruct how to built a firearm, but integrate a system into an existing firearm. Understand and follow all State, Federal and Local rules on firearms.
Leave Comments below please. If this helped you, I would like hear from you. It is the reason I create these instructionals.
Reddit user MorningStarCornDog is the original person I know of who got the RDB kit working in the EPC AR-9. the EPC is normally direct blowback in this radio delayed system is a much improvement to impulse of the round. Morningstar documented the process and this is an update making it easier for others to replicate.
MSCD’s original post
DISCLAIMER: Follow at your Own Risk. I am not responsible for your actions.
DANGER: Guns Kill – Follow best safety practices and use proper PPE. Treat all guns as loaded
WARNING: Gun modification is dangerous as ammunition is explosive, know your limits stay within them.
NOTICE: No Reactive Soda Targets or Simulated Meat Targets were harmed in the making of this video
TABLE OF CONTENTS
0:21 DANGERS/WARNINGS/DISCLAIMER
0:40 Introduction & 1st Shots
1:34 Theory, Consideration and Parts Used
2:48 Parts/Tools & Process Overview
DETAILED PROCESS:
6:20 #1 – Remove Bolt Catch
6:36 #2 – Cut Cam Pocket
11:44 #3 – Remove Mag Stop
12:02 #4 – File down mag catch (lower magazine)
19:48 #5 – Cut Mag Stop
21:58 #6 – Bend BHO Bar
23:25 #7 Reduce Bolt legs (I did not need to do)
24:06 More Range Video and Cycling
PARTS LIST
EPC Complete Lower Receiver
EPC Upper Receiver (Not complete ie no barrel)
CMMG RDB Barrel installed in EPC Upper Receiver
Charge Handle
Mags for fitment
TOOLS LIST
Rotary Tool Kit (HF Drill Master Cheap Kit)
Bastard File with one side flat
Fine Grinding Stone (optional to make Aluminum smoother)
Metal Cutter/Grinder for Mag Stop
T10 Torx
1.5 mm Allen
NOTES/ERRORS:
Section Reserved for information or errors in video.
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LOL the fact that he calls the ejector pin the mag travel stop tells you everything you need to know
Good video! Wow
Should of bought the big bore upper reciver aero LX. Anderson 458
Great video and thanks! I take it from your intro that you are a Paul Herrel fan…
Want to build an AR-9 so I just received my Aero EPC upper & lower. Starting to look at barrel and BCG options, now you've given me an idea. An idea that will probably cost me a fortune, my mental health, and countless evenings tinkering…thanks! (I think….)
Thanks Charles, for the hard work, subscribing, I see the ejection is ok, good ejection.