my thanks to everyone who has offered advice and information.
between the threads i searched and found this company D S Arms.
D S also makes a piton operated AR style rifle. Link:AR GTC Gas Trap Carbine with C.R.O.S., 5.56 NATO-D S Arms
i like the robinson but would like to learn more about the others mentioned as well as this D A Arms rifle if anyone can help i'm all ears.
I don't know a lot of the pros and cons as I have never owned and or used a piston upper but just some general observations.this morning i uncovered a company that manufactures upper receivers that are gas piston operated. link: Addax Tactical Gas-Piston System for AR-Series Rifles
maybe this is the way to go since i could utilize a common produced lower.
link: pro's and con's on this set up would be most appreciated.
i keep uncovering new companies as i search. hopefully i'm thinning the herd!
I don't know a lot of the pros and cons as I have never owned and or used a piston upper but just some general observations.
Looks like they are just assembling uppers with the PWS piston system. they are not the actual manufacturers of the parts that go into those uppers, i dunno if that matters to you or not, but it also means that you could buy all of those parts independently and assemble it yourself/have someone build it up for you. I think that Henderson Defense or Rainier Arms could produce something similar and customized for you.
If you go with the piston "upgrade" or "retrofit" then you have several different options
POF (complete uppers)
just my 2 cents