I plan on only using sub-sonic w/ my gem-tech can----------I guess if I just get a flatop upper and have a bbl setup for it---it really shouldn't be that big of a deal to have a smith set it up for me----the SSK ones are great looking, but too much $$$ for my wallet-----any advice or suggestions would be greatly apprecited

Quoted: I plan on only using sub-sonic w/ my gem-tech can----------I guess if I just get a flatop upper and have a bbl setup for it---it really shouldn't be that big of a deal to have a smith set it up for me----the SSK ones are great looking, but too much $$$ for my wallet-----any advice or suggestions would be greatly apprecited

Not that hard to build the upper your biggest challenge/expense is finding the barrel -
Randell of course can sell you one - you can also order thru other vendors SSK being I think one of the most expensive.  Mine is ER Shaw barrel found after about 3 months of looking here.
Oher components are easy and assemly requires some few specialized tools. Keep checking Equipment Exchange, and other sights (even E-bay!)  

http://www.quarterbore.net/  is good source of info.
as is http://www.silencertests.com
Cheapest prices on dies was Midway -  

Other choice is 7.62x39 but magazines are the problem with that choice...

When working up your loads for subsonic start super and work your way down to sub sonic.

Have fun...

Artful

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