03-14-2023, 12:36 PM
If this is a complete ready to shoot upper then 100% return it so they know what they did wrong, if you assembled it I agree with Montana start with the mechanisms 1st operation once you have that move on to the second. I was a machinist in the heavy repair field so it was normal to receive a project in varying sizes of shrapnel and the first rule is "first do no harm" same here, so the gas port size is your LAST option IMHO.
Easiest oops to do and fix would be gas port to block alignment, I would also work BCG in receiver by hand with and without the bolt inspecting "feel" of each part as it interacts with it's matting part....
The issue limiting your 1st operation "should" be between the gas port and the BCG and in my experience there is a "Tell" there if you can see, feel, hear it...$.02
I'm new to the AR but have 4 decades of troubleshooting and repair under my belt and the process is the same no matter what the machine is.
Easiest oops to do and fix would be gas port to block alignment, I would also work BCG in receiver by hand with and without the bolt inspecting "feel" of each part as it interacts with it's matting part....
The issue limiting your 1st operation "should" be between the gas port and the BCG and in my experience there is a "Tell" there if you can see, feel, hear it...$.02
I'm new to the AR but have 4 decades of troubleshooting and repair under my belt and the process is the same no matter what the machine is.