9mm AR mag block question

[docsprague]

Decided to SBR a spare lower and build a Colt SMG retro gun. So far all I have is a lower (not a 9mm lower). My question is how hard is it to install a colt roll pin 9mm mag block in a lower? I have two well know rifle builders in my area with CNC machines so I would think it would not be a problem. Is it even worth doing or are there drop in mag blocks that function the same and are just as reliable?

I have been looking at buying a Colt SMG kit but they seem to be rare these days. Any other options that would still give me a retro (A1) look. I thought about buying one of the new 6451s and finding a A1 upper and having the barrel shortened. Kind of a pricey option but I could at least have the barrel threaded to a more suppressor friendly thread. Since I already have the lower pending, might be a waste to strip the Colt 9mm lower.

[usmcvet]

What route did you go? I have a 9mm Colt upper in my parts collection. I bought it to build a .22 upper. I ended up buiding a few M4 .22 uppers instead.

I am looking at a RRA 10.5" bbl I found them here for $205. http://stores.9mmar.com/rra-9mm-10-5...rrel-assembly/

With the http://www.brownells.com/rifle-parts...-prod1548.aspx

I really want one of the Angst Arms UPD-9 SBR's. http://angstadtarms.com/udp-9/ The fact that it takes Glock magazines is the main selling point for me. I think this is the better choice. Mags are readily available and high quality. I don't see Glock mags going away anytime soon.

[Singlestack Wonder]

Has anyone seen any reviews of the Angstad Arms lower receivers or complete weapons?

[Mad Machinist]

I've had a LOT of success with the magwell adapter sold by PSA with uppers I'm building....most of the feed problems people report are not really lower/adapter related.....problem is usually the way the barrel is made......I had a personal 9mm that someone just traded me out of that ran perfect...so perfect they had to have it.......... it was built with a Promag adapter and was running Promag all polymer mags...LOL....on one of
my barrels....they have 1500 rounds through it without a malfunction.

[Singlestack Wonder]

Mad Machinist...

Could you elaborate on the barrel issues you mention above?