Ultimately, I just don’t think an X39 is a good choice for the AR15. If using a regular lower, then the magwell has too long a straight section and the rounds don’t stack right in the mags. Go to an AK magwell, now there’s no BHO. The charging handle just wasn’t intended to be used every mag change. That’s ultimately why the new Bren 2’s have their own proprietary mag....to avoid all of these compromises.