They are not against the law in nearly all states and definitely good to go in Texas! Find a class 3 dealer and he can talk you through the paperwork and extended atf background check requirements. If you can own a firearm, then you will pass the background check for any NFA item be it a DD, SBR, MG or suppressor. There is a one time $200 tax for each NFA item. IM me if you have any questions.
.50 BMG Supressor. Nothink like shooting a Barrett without needing hearing protection.