I'd like to chop my PTR 91 down for better handling running a can. When you chop an HK profile barrel, is there enough meat left to thread 5/8 - 24 or will I need to stay M15x1? I have a Dead Air M15x1 flash hider but I'd rather run a SOLGW NOX mount on this rifle. What can you cut these back to and still allow the charging tube cap to be removed? Thanks!