They admit it's out of spec - Tacfire AR-15 Buffer Tube Kit

I bought a few of these for cheaper builds and am not impressed! They mic out smaller than milspec so I figured something went wrong with the production process. Emailed them and they responded acknowledging that they do in fact manufacture them to a smaller diameter. None of my 4 stocks that are waiting to go on builds would lockdown with the friction lock. They advertise them as milspec but they aren't. Don't get your hopes up if you order these.