Reese I just went and double checked your order. Nowhere in it is any mention of any kind about a 1/2-28 thread. If you want to change it now we can still do that but you would need to send it back in.
Your barreled action was not actually ordered as a 223AI, it was not an option of the original deal. You used the order notes to tell us that you wanted a 223AI (not an original caliber offered). We did it without any surcharge, as discussed, because of the lengthy wait involved to get the receivers.
As
@spife7980 said, the caps are provided as a FREE accessory. Your order stipulates that you dont want a blended cap, or a muzzle brake.
The 5/8-24 thread is, by far margin, the most popular thread for precision rifle barrels in the North American market. There are literally hundreds of brakes available on the market in 5/8-24. Including, I might add, the Jetblast brake that we make. Then again, the Jetblast comes in 1/2-28 as well.
The odd cut you mention is called a chamfer. The chamfer functions as a protection against damage to the shoulder edge such that a ding wont leave a raised location and cause an eccentric misalignment to the muzzle device being used. In my time making rifle barrels I have seen a number of ways that field-created damage can cause accuracy issues or thread problems. A damaged shoulder is one way that has been shown to gall and misalign. So therefore we remove the possibility of it happening. Same root cause as to why we use a truncated lead thread on all muzzle threads, user level damage protection.
The barrel is contoured to maximize grip with the workholding. We covered this in this thread a couple times. For years we have done things this way, performance is never in question, and it can rarely be seen except by measuring sequential marks along the length.
@Ksracer the only marks I see near the crown appear to be latent dirt, some kind of fuzz or something, there arent any machine marks on there. The muzzle threads come lightly greased prior to final assembly and shipping. Dry SS threads are notorious for galling together therefore parts are always greased for assembly.
If there is anything else you do not understand about your barreled action I would be happy to explain it to you. It seems that your expectations and your actual order differ, and since we work to the actual order I want to clear this up. Publicly posted screenshots are available if need be.