Mags for AR-9: ASC or Metalform?

[wanderson]

+1 to all this. I bought a load of them when they were available for $10 each. I still have plenty that are NIW, but all that I've tried have been 100% in my Colt 9mm SBR and my RRA 9mm SBR. Oddly, I have one plastic Promag and it's been 100% too. BTW, the RRA 9mm SBR was unreliable with the C-Products magazines, but has been 100% with the Metalforms.

I think that may be because if your RRA 9mm was like mine, it has no feed cone, just a chamber that completely supports the round. Great for hot loads as it’s got maximum case support, but if there’s any issue with the feed angle, it’s a malfunction. So having a good mag feeding at the correct angle is important. Usually feed cones are more important with Glock builds since they can’t feed as low as Colt pattern mags. Personally, I like max case support in case of an OOB and tend to save the NATO and +p loads for my AR9s.

[azlester]

I had a friend send me some ASC mags for my Hahn adapter set up... the followers were too long and kept hitting the mag stop...wouldn't allow the LRBHO to function at all and also caused problems with the last 2 rounds feeding properly... had to do some serious surgery on the followers to get them to work properly. ASC customer service was worthless when I asked if they had any new design follower in the works or suggestions on getting the mags to work...they couldn't have cared less.
The Metalforms are 100% and worth every penny!

[azlester]

I had a friend send me some ASC mags for my Hahn adapter set up... the followers were too long and kept hitting the mag stop...wouldn't allow the LRBHO to function at all and also caused problems with the last 2 rounds feeding properly... had to do some serious surgery on the followers to get them to work properly. ASC customer service was worthless when I asked if they had any new design follower in the works or suggestions on getting the mags to work...they couldn't have cared less.
The Metalforms are 100% and worth every penny!

[Bzajdek]

I have had zero issues with metalform in my psa colt rifle, I have not tried any asc mags yet but if they are not significantly cheaper I am not sure I would change