A few months back, you guys were trying to help me figure out what was wrong with my most current build (604). I thank you all for all of the effort.  We left off with me having swapped bolt/carrier assy.. I also swapped lower (including buffer/spring/tube) I even swapped upper receiver. I did all of this swapping 6 times, (robbing parts from my other AR,s) I tried 5 different types of ammo. I had the sight base of numerous times cking to be sure gas was flowing properly through the sight base. I ckd the gas port size. I even installed a new gas tube (as a last resort).  At this point it seems OBVIOUS, there must be something wrong with the barrel?????? So, I tried polishing the chamber (thinking the brass may be hanging up for too long during ignition.  Well, I explained all of this to AR15Sport (where I got the barrel) and they were good enough to send me another barrel with a return shipping voucher. Yes, they trusted that I would return my barrel to them, after receiving my new barrel. What great guys to deal with!  Anyhow, I installed the new barrel, and,,,,Yeah!!! It finally works. Heres a few pics.

nice looking rifle

Wonder what was really wrong?

I like it! I have a 604 that looks identical and its my favorite. Happy to hear you got it fixed. I'm sure it was a relief!

I love happy endings.

The wet poncho liner and rain drops are nice touches.  Now you need a muddy pair of jungle boots to go along with.

AR15Sport promised me that they would notify me of what is wrong with it once its been ck,d out. I just received the notification from UPS that it was received today. I,m kinda hoping that they will sell it back to me at a reasonable price (to be used for a dedicated .22 upper)

thanks for the update glad you finally got it working dog :)

I had to open up the gas port on a Green Mountain barrel A1 profile to get the rifle to cycle. It was from a batch manufactured about 2 years ago. That cured the short stroking ( after checking everything else was in spec, as you did)
DanG

Actually Dan, ARSport did have me open up the port "Just a tad" ,but,,,it didn't help. Still waiting on them to contact me with what was wrong with it. You guys will be the 1st to know.

I also bought one of those barrels and had the same problem. Not willing to deal with it at the time, I removed it from my receiver and set it aside. Long story short - I ended up including it in a trade to Braceman (with full disclosure) and he discovered that the FSB was loose.

He reamed and re-pinned the FSB with taper pins and worked just fine.

A woobie in the rain brings back certain memories....

Glad you got the barrel sorted out.