RRA 9mm upper?

[TacDoc]

I want a 9mm AR. For now I'm still researching/planning my setup.

I was looking at this RRA upper:





I do prefer a regular FSB in this upper, so here are my questions:

1. Is this Weaver Type Gas Block Sight Base is .750" in diameter?

2. How does this gas block attaches to the barrel? Just tension screws or the barrel is somehow modified?

My idea is to remove this gas block and install a BCM "F" FSB with 1/8" straight pins.

Any help will be appreciated.

[Buck]

How does this gas block attaches to the barrel? Just tension screws or the barrel is somehow modified?

I believe this is just being used as a front sight base and not a gas block. You may want to check with RRA but I believe it is attached only with set screws.

My idea is to remove this gas block and install a BCM "F" FSB with 1/8" straight pins.

That being said I would purchase a complete 9mm CAR upper with a "F" FSB that is pinned in place, and the handguards or rail system that you want, directly from the factory.



If you want the barrel shortened for a SBR, and a 9mm hammer installed, or the bolt ramped for use with a standard semi auto hammer, you can have these things done by any competent AR smith.

Or better yet ADCO firearms makes a SPR version of what you want and they can ship it with a pre ramped bolt or a 9mm hammer and buffer, which ever you prefer...

Just my .02

[CONKLE73]

RRA 9mm is a nice colt copy!