Reviews & Ratings for Primary Weapons Systems MK1 MOD 2 Upper Receiver — 2 reviews — Page 1

Yes the caps lock was necessary in the title. This upper is an amazing piece of hardware and well worth the price for what it delivers. I have about 6000 rounds thru it already and not a single malfunction, maintains sub moa groups even when heated up o.O couldn't ask for better

Bought this upper December 2017, wanted to put at least a thousand rounds through it before reviwing. Only thing to say is that it is awesome!!! After first seeing the complete rifle on Sage Dynamics utube channel, I knew right then I needed to have one. I did not want to buy the complete rifle because I had an extra lower laying around. I would recommend thst you go to the Sage Dynamics utube page for the complete review, it works just as exactly as Aaron Cowan explains. Always heard of bad things about piston guns, but this one is completely different...it uses an AK style piston system. So much less wear and tear on the bolt and it is also gas adjustable (really nice). It is so hard to explain how wonder full this upper is to shoot. If you are on the fence about piston driven uppers, you need to give this one a try. I guarantee you will not be disapointed. Much cheaper than the Pof upper and more choices in barrel lengths too. Big shot out to Optics Planet for selling these upoers!!! Oh, by the way...I purchased the Mk111 Mod 2 (11.85" barrel).