My Dillon 650 was set up for 9mm Luger, which I don't bother to reload now because factory ammo is so cheap. So when I started shooting .375 H&H it was natural to convert the Dillon over to that caliber. The conversion was rather expensive and there are complications to getting good loads on bottleneck cases that need to be lubed, but that all got worked out ok. Until the time I went to place a bullet in the .375 case and couldn't do it because the case was OVERFLOWING with powder. To this day, I can't say what it was that caused the overcharge but it taught me a lesson- only reload on a press that will allow a visual inspection of each case before bullet seating. The .375 case is so long that you can't look into it on the 650, the press frame blocks the view.

Again, thanks again for all the replies. Gearhead Jim...I am using my AT500 for this project. I will be using a scale to measure each of my charges and charging the case manually. I like the AT500 since it allows me to use all the Dillon accessories I want, and still have the same control as if I were using a single stage press.
Now for the rest of the story...I finally got an e-mail from the head of customer service at Dillon. He said there is a larger shell plate and is supposed to be sending me one. I hope it will be here this week and we shall give it a go.
Thanks again...

That IS good news. Now it should hopefully all work out.

My Dillon is a 550, as mentioned, but I too am a bit leery of not visually checking every charge in rifle cases. What I've been doing is putting a .41-caliber funnel in the powder-measure die and just dumping the weighed charge through that into the Rigby case. It seems to work alright, but maybe I'll get an AT500 powder die which has the funnel built in.

Keep us posted on how you're doing with the new shellplate?

Ooooops...I'm not dumping charges into "the Rigby case" on the 550....! I AM dropping charges into the .404 case. The .375 Ultramag cases (which I reform to .404s) have the H&H head size and work in that shellplate. Sorry for any confusion. Actually, I still load most of my rifle ammo on a Rockchucker or my old Lyman turret press.

Thanks George.

Well, the saga is over..I received my new shell plate today and it works like a charm. It is bigger than the .460/.378/.416 Wthby shell plate. So if any of you run into the same problem these are the numbers on my new shell plate 12808 / 550 #T SHELLPLATE PART

Sounds cool,
With so many rounds loaded up I'm confident that you'll make the major power factor cut-off at the next IPSC or Three Gun match.
JCN