Ok, just got back from the range. After all the modifications to the 7.62 TOBR to make it a featureless rifle, it functioned flawlessly and the first three shots were in the bullseye. 'Nuff said.
The new build based on a 7.62 TOBR Field Grade barrel didn't fare so well. While the rifle functions wonderfully by hand, with no magazine. It doesn't seat a round fully when it has to strip a round from the mag. I changed the red spring from the TOBR into the new one (Tubbs flatwire spring was in new gun). Still no go. If I dropped a round into the chamber and charged the bolt (no mag). It would fire but the casing would end up stuck on the extractor (Hint maybe?)
Installed the TOBR bolt into the new gun, works like a dream. Put the Tubbs spring back in, works like a charm... Sighted in the weapon and then put all the TOBR parts back in the TOBR..
I did make sure, after the intial malfunctions that the Lantac E-BCG was sloppy wet, made no difference. I removed the bolt from the gun to checkout the extractor. The bolt doesn't extend or retract very smoothly, it's almost like it has a suction to it as well.... Not happy!!!!!! This bolt was $325 and a two month wait!!!!
Also, I did notice the Tranquillo muzzle brake was not nearly as effective at reducing felt recoil as the old style Surefire on the TOBR. Might switch it to the 6.8 and put the Smith "Good Iron" brake on it. The Smith doesn't have the shoulder the TQ does so some very shiny metal shows where it mates. Which was why I removed one from the new gun to begin with.....