Dollar Store Toy Baton Barrels

mig and badwrench have been working with these toy baton barrels, as they have rifling built in. I haven't had alot of success with them with stefans. I have seen benefits for streamlines, but it hasn't worked consistently for me. I tried sanding the interiors today and saw good results. Streamlines are more consistent now even at range. I still get spiraling darts occasionally but even they land close to the target. I think with some dart cherry picking I can actual use streamlines now! With some tweaks this could also be an alternative to petg that's available locally (for some).

Please excuse my dollar store sandpaper as I don't use much. I mention it because I doubt good 60 grit sandpaper will be right for this task. Try something finer I guess. I found a tube which was a good fit when 1 layer of sandpaper was duct taped to it. Sand in 1 twisting direction till it's close and then try sanding through the barrel. Clear out the sanding debris alot. I went through 2 pieces. I sanded until I got an air fit. The tubing was .435. It wasn't tricky although one end was sanded a little more than the other.