I find that when my 550 starts getting sluggish, it's usually time for a good cleaning. Sometimes those nasty primer anvils get stuck in the works and are difficult to see. Dillon has great customer service and they've sent me parts over the years to replace broken and worn things. I did install the automatic primer feed and it works well. My press is an early one and is actually a 500 and not a 550. I can't even begin to estimate how many rounds I have loaded with it. I've owned it almost 40 years. One of the best shooting investments I have made.