DaemonAssassin
Why should we Free BSD?
I'd like to thank DaemonAssassin for his generosity. He set aside time and resources to teach me how to lap an upper. He really knows his stuff.
I brought 2 BCM blems ($59 each...they come with forward assist and ejection port covers). I also brought 2 garbage blem uppers that I purchased a while back. They were super cheap at $29. AO Precision if I recall correctly. Not to be confused with Aero Precision.
Interesting lesson about quality. You could tell very quickly how much better the BCM product is compared to the cheaper option. It took no time at all to remove the anodizing from the AO upper. The BCM took a good bit of work to properly remove the anodizing.
We had to be really careful inserting the lapping tool in the BCM upper as it was a tight fit. The AO upper wasn't as finicky.
Here are pics of each brand after lapping. You'll notice the BCM upper still has a little anodizing on it.
You're welcome! Happy to see that you like the work that was done and you picked up a few new pieces of information to use. If you need to use my bench or tools in the future, don't hesitate to reach out.