Maybe I just wasn't meant to build Ar's
I just finished my build and grabbed a cartridge to be sure it would chamber. Loaded it into a mag inserted it into the rifle with the bolt back and released the bolt. The bolt wouldn't go all the way forward and when I pulled the charging handle back it wouldn't budge. I ended up removing the buffer assembly and the bolt was at least 1/4 to the rear of where it's supposed to be. I removed the pivot pin so the rifle would come apart and ended up having to tap the carrier with a punch to get it to slide back. When it did the cartridge slid out of the barrel.
What might of happened to cause this?