most likely its best for me to but my question is why can you buy gun parts and put them together but i cant make a gun out of a pipe and some wood? since its not worth me gerring throwin an jail for i wont be making one but i do think they are cool
You can, so long as you are otherwise legal. That includes not running afoul of the AOW restrictions. Make it fit an exception to AOW such as "other than a handgun with a rifled barrel." Or make a standard, but not SBS or SBR, shotgun or rifle. If what you want to make falls under the NFA restrictions, you must pay your tax, submit your paperwork, and await authorization.
This says nothing about WA restrictions, which currently prevent ownership of SBS and SBR.