Quote History Originally Posted By s4s4u:
That is a blowback lower. As was indicated in another thread it may be possible, but not without some work.
@amphibian
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Quote History Originally Posted By s4s4u:Originally Posted By DOG556:
Can anyone confirm , will a CMMG complete RDB 9mm-Glock mag upper work on a RRA Glock mag pistol lower??
That is a blowback lower. As was indicated in another thread it may be possible, but not without some work.
@amphibian
Yeah, it is hit or miss.
1. You will at a minimum need to remove the fixed ejector in a straight blow back lower to work with an RDB upper since the ejector will be in the bolt for a CMMG RDB Guard/Banshee or in the upper receiver for a CMMG RDB Dissent.
2. High probability that the 'ears' of the feed ramp block will need to be trimmed down to clear the lugs of the CMMG bolt.
Picture below from my site shows an example:
3. Lastly is where it is hit or miss in regards to the feed height. Most Glock lowers present the mag too high for the CMMG system but there are some that work with no mods. I have a buddy that has a cheap PSA Glock lower and all he did was #1 above and it was drop in for his CMMG RDB. My picture above is of a New Frontier Armory S-9 (Scorpion mag lower) which also works with no mods to the mag catch to adjust the feed height.
Here is a link to my site where I detail what I did to get un-modified Colt mags to work with the CMMG RDB:
https://c3junkie.com/?page_id=374 What I didn't do yet is TIG weld a stop in the mag block to prevent over insertion of the Colt mags meaning that if you put upward pressure on the mag, it will jam. So keep that in mind if you find that you need to lower the feed height. You need a way to prevent that or maybe you don't care and never push up on the bottom of a mag while firing.