Ok, so after shooting the rifle all day I was really frustrated because I couldn't get this thing as quiet as my marauder. I was close to tearing down the shroud and remaking it. Turns out the rifle was shooting way hard. Decided to turn down the power, and found that the hammer spring adjustment is a complete piece of junk! Totally stripped out the hex socket and still couldn't get it to move even after heating it up and completely tearing the thing apart with a tap extractor.Made a new adjustment screw assembly and did a few more phone book tests (I don't have a chrony). After getting it all set, its as silent as my marauder.One thing I can say, this rifle is scary accurate!