Original 18 inch barrel is restricted yes. 18.75 inch barrels use to be available to install and get the gun into the nonrestricted class. I did one several years ago and kept the original barrel just in case I want to go back to original, so not really bubba'd with just a barrel change. It's funny when comparing the two barrels side by side; the difference in length is not even the width of my thumb but is big when it comes to classification. Keep looking and if buying a restricted class it will be cheaper than buying a nonrestricted one. Don't pass up on a GI with the barrel done though as you should be able to find someone to sell you a GI length barrel if you have your heart set on a restricted original config carbine. Watch out for the non restricted commercials though as quality varies.