Update: I seem to have fixed my rifle. The smith said the rifle "beat him" and he gave it back to me yesterday and said he couldn't get it to work. The bbl and gas block port were matched at 4.5mm and it still wouldn't run. It was still undergassed.
I got it home last night, took it apart and measured the piston head (as I had asked him to do back in January).....lo and behold, the piston head was UNDERSIZED at .4685".....the standard piston head is .471-.4715". I then measured the piston in my Century VZ.....it was .473".
So, I swapped the Century piston into the D-Technik SBR.....and IT RUNS!!!
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Ran 120 flawless rounds of Brown Bear HP ammo today. It won't run Golden Tiger reliably still (might have to get the Dlask brake to make it run that ammo).....but I didn't expect it to since Golden Tiger is supposedly weak anyway.
I just bought a Draco AK pistol b/c the D-technik wouldn't run reliably.....glad to see the tax stamp won't go to waste on the VZ
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. I much prefer the ergos and weight of the VZ to the AK as well as BHO and overall quality so I'm glad to see it run. I just wish it wasn't ammo specific. The AK ate everything I fed it today so I'll be SBRing it too eventually.
Regardless....after 9 months of working the VZ SBR project, I finally made some headway today and I'm excited!
Sean