I have an IMI semi auto Uzi that I wish to SBR. The Uzi is nearly new although it was made in the 1980s. I want to use different calibers with it. If I engrave it on the receiver I can see how this can be done. I would like to avoid this, so I am looking at engraving the barrel. Is it passable with the BATFE to engrave a barrel of each caliber with the information? If not, what would you do to allow the use of different calibers. Also, if this has been addressed and you can, please post a link. Thanks