Quote from: HufD63 on January 22, 2021, 04:13:54 AMI'm thinking an Aero M5 upper from everything I've read now.
I built a 308 with one of their builder sets a couple years ago. It's pretty sweet, but I had the wrong spring in when I first put it together, and the bolt velocity was very high. Putting the higher power buffer spring in resolved all of the cycling issues. I also used an adjustable block to allow for suppressed use as well. Still havent completely fleshed out all of the settings for it, but it is not 100% reliable when switching from suppressed to unsuppressed. It doesn't really matter, as long as it is reliable suppressed, which is the way I shoot it 99% of the time anyway.