Had an itching to see what the fuss was about with Piston ARs, so I took matters into my own hands using a registered lower I already had, just making some upgrades along the way.

Upper Specs
Aero Precision Upper receiver
Midwest Industries 9.25" Gen2 Quad Rail
10.5" Faxon 1/8 for the 55gr Wolf Gold I shoot
Silencerco Trifecta Flash Hider
Troy HK Front Sight
Troy DOA Rear Sight
Superlative Arms Carbine Piston Kit
AIM Surplus Bolt
Standard Charging Handle
Tango Down Foregrip
Streamlight M951 (on opposite side of gun)
Vortex Sparc AR red dot

Lower Specs
Bushmaster XM-15 Registered Lower
CMMG Lower Parts Kit
BCM Trigger Guard
Mil-Spec Receiver Extension
QD End Plate
VLTOR IMOD Stock
BCM Gunfighter Mod 3 Pistol Grip

I also have a Saker Suppressor and I plan to see how many rounds I can shoot through this rig before a stoppage without cleaning. At 150 rounds so far, but I only had time to function check this weekend.  I plan on putting another few hundred rounds through next week, more if time permits and weather holds.

Observations so far are, it has indeed run super clean. Outside of initial lubrication as part of assembly, no other oil or cleaning has been done, and I won't do any until I have a failure.

Anyway, here is the weapon

Attached File

UPDATE -

Another 200 rounds bringing up the total to 350.  I've run it with a combination of Wolf Gold, Federal, IMI, Black Hills, and American Eagle types of ammo both suppressed and unsuppressed.  No malfunctions other than a couple fails to lock the bolt back after the last round.  Oddly enough, it was with the suppressor.  Like I said, it happened twice total.

So far, it's been running great!

Awesome build! I kinda want a piston rifle

UPDATE-

It's been 90 days and 500 rounds. Still running like a sewing machine, and the 1:8 Faxon barrel is dead nuts accurate. I never would have guessed this would have ended up being a 1 MOA rifle!  It's crazy!

Upgrades - I installed a Geissele SSA-E, Adams Arms bolt spring, and a POF roller cam pin.