MecGar makes 18 rounders which are quite good. You can find cheap mags for the M9, if you don’t mind 15 rounders. How does the aftermarket compare? It’s a pretty mixed bag. The P320 has a nicely sized mag release that is easy to press as it comes from the factory.Model : SM-J320P | Samsung Firmware Database.We also take the opportunity to see what has changed in the P320 series. We take a look at the differences between a Sig P320 Compact and a Sig P320 TACOPS.