I have 4 Ammo-plants, all 4 work perfectly. The first one I bought was new. After about two months I learned how to time it perfectly, and even made a kit to do this in about 3 min. here is the kit I made.
Now the first used press I bought was from a "GOOBER" that did nothing but bad mouth the Hornady press, stating that it was a piece of crap and in a year he had not been able to make one round of ammo. I finally got pissed and offered him $150.00 for the press and $100.00 for his case feeder, and told him that I was not interested in his Mr. Bullet feeder. He accepted my offer.
I C-clamped it to the bench and in 10 min I made my first round.The pawl for the dies was 370° off and the pawl for the primer was sheared off, and I had to replace it. Now this is when Hornady came out with the .22 and 30 cal bullet feeder. So my order to Inline and Mid way cost a lot more than the press.
Now my second used press was a little different. I saw a listing in craigs list for a case feeder. When I got there he explaned that the press was under water for 7 day during the flood but the case feeder was above the water line, but it sat for 3 years after the flood. I turned it on and it ran fine and he only wanted $200.00. While we were talking I looked into his trash can and there was the press so I asked him about it. He stated that it was frozen up. I offered him $50.00 for it. It took about a week to get it going again, and that was with the help of a torch and dry ice.
Now for the third used press,It is a complete Ammo-plant. He warned me that the priming system has not worked for at least a year, and now it is having problems with the dies lining up. So I took it apart and cleaned everything and timed it.The first three rounds of 9mm (because that is what he had set up on it) ran smooth but on the fourth the press jammed up. I took the primer drop tube off and found a primer sitting on edge jamming the slide. I took it back a part and polished it. I ran 6 more rounds with no problem and it jammed up once more. I took it apart and found the primer was up side down. BINGO. I grab a large primer and dropped it down the primer tube and it went down with no problem. I then took it apart once more and replaced the large primer drop tube with the small drop tube. I have now made 500 rounds with out a problem.
Now this proves one thing...It may not be the MICKEY MOUSE engineering, it may be GOOFY. GOOFY is that guy that is looking back at you in the mirror.
Now i do have a friend that has a Dillon 650 that had a full primer tube explode. He did not load for 9 months but still to refuses to prime on the press when he found out he was not the only one to have this problem. I have not heard Hornady having this problem.