Anouther fix besides electrical tape (if you don't want to make your gun look like it was hacksawed together) is super glue. No don't glue the hopper to your gun!!! Make lines down the langth of the feed tube of the hopper with the glue. Make sure there dry before you insert it back into the gun. Start with three or four lines and if it's still lose add some more, this way you can avoid those embarising Tape lines on your spiffy guns.