After several attempts in building an ar9(pcc)... - Mean Arms 9mm Ejectored EndoMag - 3 Pack

This 9mm PCC conversion by CMMG along with many of their variety of AR Caliber conversions, this may seem like the easiest route.

After doing so much research on Blowback9.com, I decided to go with a FM9 Upper Receiver and a standard AR Lower. Let me say the ability to use JHP 147 and 124 (even +P's) was flawless. I practice even with Federal Syntech. There is a difference in the FM9 among other barrels out there, some just don't have yhe angle to provide some sort of feed ramp for a flat or jagged nose HP or Synthetic round. I did not have to break in my barrel either.
I've ised these magazine conversion with PMag M2 and the M3 windowed and non-windowed, no issues. The different lowers I have used are Aero Precision, PSA, and Anderson, standard LPK's and even some with RA140 triggers(non-PCC), all us8ng a standard Carbine B7ffer and even an H2.
Overall I usually get the 3 packs on sale or with a discount code saving me a little, costing me a net of $35 per mag for a Gen/M2 PMag and about $40 for an M3, with an additional $5 for windowed versions.

I am extremely happy with yhis purchase and will continue stocking up on them as the become more available.

A safety reminder, ALWAYS check the BCG when the magazine is out, because the ejector is on yhe magazine and the BCG can hold a round. You don't want an accidental discharge.