I tumble with pins. I sold all my other vibratory cleaning equipment last year due to the ease and effectiveness of wet tumbling. The only cases that really give any trouble are the 25 calibers. The pins like to catch in the mouth of the case. Not a big deal but still a problem. Easy enough to fix with a tweezer though. I have a friend who ordered some of the stainless chips and those seem to be the way to go and eventually I will get around to ordering some myself.