After my last thread regarding the DD upper and how the port hole was in the .080's. I now turn my attention to the BCM upper with the DD mk18 rail. I know someone here has got to have use these before. How do they do suppressed and unsuppressed? I'm finally building a SBR as a "gift" to my self for how well I've handle having diabetes.
I apologize in advance if this is the wrong section.

