cleaning brass

for years ive been just running the brass through a tumbler. the outsides get really shinny but the insides are still pretty dirty. my question is does the inside of the casses have to be cleaned for accuracy.
does anyone have a sonic cleaner that works good on the inside. I can run them through that and then run them through the tumbler
thanks for the help

I've been using just a tumbler for many, many years. The last thing I do before I prime my brass is brush out the inside of the cases. When in a big hurry, I will not brush them out, and as far as I can tell, accuracy does not suffer at normal hunting ranges. If you are a serious, long range shooter, you might see a difference at 600-800-1,000 yards, but that's a whole different shooting world than mine!

Whether it makes any difference is debatable. But I can assure you that it will be so minute that nobody you know will ever tell any difference if it does.

All I've ever done in tumble and its worked fine for me.

I think with most things reloading consistency means more than anything.

Same head stamp, same number of firings, same brass prep for every case, etc. should give you the most consistent results.

I only tumble mine and the insides do not come back shiny clean, but they are all equally dirty if that makes sense.

I only tumble my cases clean, and don't mess with the inside. The inside gets clean enough that way.