I haven’t heard of an impeachment proposal.
Maybe you are referring to this ...
http://radio.woai.com/cc-common/mainheadlines3.html?feed=119078&article=10700507
A Texas lawmaker says he plans to file the Firearms Protection Act, which would make any federal laws that may be passed by Congress or imposed by Presidential order which would ban or restrict ownership of semi-automatic firearms or limit the size of gun magazines illegal in the state, 1200 WOAI news reports.
Republican Rep. Steve Toth says his measure also calls for felony criminal charges to be filed against any federal official who tries to enforce the rule in the state.