I have had my dillion 550 press for 6 years now.It is sarting to give me a few problems.It wont size cases in forming cases I dont think it will go down far enough.The primer system has given me fits.The powder measure is starting to loose its accuracy.I have loaded about 20,000 rounds on it at least.I load from the little 32 H&R mag to 454 and in rifles from 222 to 416 Rem mag .Has any one else had any problems with theirs?

I have a 20 year old 450B (in 45ACP) that used to load over 1,000 rounds a month on for IPSC shooting. Conservatively, it has over 50,000 rounds through it and except for cleanings it has never had any work done on it. The powder measure has never been adjusted after the intial set up 20 years ago, so there's not much to wear there.

I would give Dillon a call and see if they can help.

My Dillon is 10 or 12 years old and I load several calibers on it. I have the quick change setup for each caliber. Expensive but nice.

I have never had to adjust my measure once set. I used to load 40S&W for IPSC for the better part of 6 years. I have no idea how many rounds that works up to with practicing once or twice a month plus the actual monthly shoot but it is a bunch. I check my measure on a scale before, during, and after each use and it still throws the same charge it did when firts set up all those years ago.

I have the Dilon SDB and after about 20,000 rounds or so the plastic primer cup seems to wear out. Its on the bottom of the primer feed. When it starts getting a jam once in a while, or a sideways primer, just replace it.
The powder measure has always been right on and never given me any problem, but I use powders that are easy to meter like Clays, 231 etc. Dillons are known to not meter the stick powders like IMR4064 very well.