Initially I did not clean cases intensively, just opting for the brush and cloth clean before de-priming and resizing [once-fired] brass. The primer pockets never cleaned up that well even with a brush and pocket reamer. And I noticed that there was sometimes some carbon in the aperture between primer pocket and case. If I found it, I poked it out. I wonder how many I missed and whether they could marginally affect ignition?
...But now I am converted to the ultrasound regime. Cases clean up well, primer pockets even better. Per AN DU RU FOX's post in #10 above, 30 cases in 1.5l of 70'c water hot water solution containing half a teaspoon of granulated citric acid monohydrate plus 2 small drops of Sunlight for 6 mins delivers newish looking brass per images below. After a quick rinse under a running tap, 15 mins in an oven at 90'c gets cases toasty enough to evaporate all residual water.
...But now I am converted to the ultrasound regime. Cases clean up well, primer pockets even better. Per AN DU RU FOX's post in #10 above, 30 cases in 1.5l of 70'c water hot water solution containing half a teaspoon of granulated citric acid monohydrate plus 2 small drops of Sunlight for 6 mins delivers newish looking brass per images below. After a quick rinse under a running tap, 15 mins in an oven at 90'c gets cases toasty enough to evaporate all residual water.
