Hi,
I'm having repeated issues with the Orca barrel mounts.
My first build lasted about 25-30 rounds until the bolt lugs jammed in the barrel. I was zeroing an optic at the time, so the rounds were not fired in quick succession. The barrel index pin deformed the left barrel mount clamshell which allowed the barrel to rotate counterclockwise (looking in the direction of fire). The barrel mounts were purchased from HT. Assembly was done carefully following the instructions and video, the barrel had to be pressed into the upper for it to fully seat, everything was nice and tight.
I installed my muzzle device before installing the barrel in the upper to avoid damaging the mounts.
I reprinted my upper in PET-CF to account for some annealing shrinkage on my first test. I printed two sets of barrel mounts in PET-CF. I annealed one set, accounting for shrinkage, and did not anneal the other set. The un-annealed set of barrel mounts had better fitment so I used those.
After reassembling I cycled dummy rounds 100 times and everything ran smoothly, the barrel was straight and the bolt smoothly went into battery every time. I was able to live fire 3 rounds before the bolt lugs jammed in the barrel again. After disassembling I found the same problem. Left side barrel mount was deformed by the barrel index pin, which allowed the barrel to rotate counterclockwise.
Has anybody else experienced this? Any ideas what I'm doing wrong?