I just set up a new to me but used Dillon 550 that has a brand new powder measure (as part of quick change kit). This is my second 550.

I am seeing a .4 gr difference in powder drop that seems to be linked to having a shell in the sizing/decapping station. With it is dropping 4.9 gr. Clays. Without 4.5 gr. It is pretty consistent.

Anybody have an idea what might be happening.

Start over with your setting of shell plate,powder drop adjustments.
make sure powder container linkage goes thru full throw.
only takes a couple thousand off to throw drops off.
one more thing is die holder,it could be rocking up.
Had that happen on my first 550,so I center punched the sides of holder so they are very tight.
They now make shim kits for that slop now.

Snug the shell plate up. Snug the failsafe rod up. Make sure you have the pistol metering bar in the measure.

When you snug the shell plate up, don't forget to tighten the set screw on the ram (raise the ram all the way up to see the screw).

Thanks for the great advice. I did it all and several areas were not set up correctly. All of these made a noticeable improvement. As I went through all of the steps I realized there was also significant static in the powder measure. I cleaned it up and wiped it down with a dryer sheet. When it all came back together it was good. I appreciate the knowledge you all share!

quote:

Originally posted by BillyBadBass:
Thanks for the great advice. I did it all and several areas were not set up correctly. All of these made a noticeable improvement. As I went through all of the steps I realized there was also significant static in the powder measure. I cleaned it up and wiped it down with a dryer sheet. When it all came back together it was good. I appreciate the knowledge you all share!

Especially here in dry AZ, I see static cling in the powder measure, more or less depending on the powder. What I have done, that helps somewhat, is to run a ground wire to the house's electrical ground (inside a box), with an alligator clip on the other end that clips to my powder measure. This helps to a certain extent, but does not eliminate all clinging. At least it is a solution of sorts I don't have to fool with. Beyond that, I can tolerate some minor difference in charges for simply reloading pistol rounds for matches.
 

Suggestion, if you're using Clays, invest in the smallest powder bar that Dillon offers. It will make your loads much more consistent.

I don't know that this is related to your issue but it was a recommendation that Dillion made when I was getting inconsistent powder drops (but I don't recall that the variance I was getting was a large as what you're getting).

Two other thoughts - call Dillion (if you haven't' already). The guys that answer the phones were previously part of the team that assembled/repaired the machines. They know them inside out. Also, Dillion has a program to completely rebuild a machine - they charge a pretty modest fee (mostly to cover the shipping). The customer service folks can give you a RM number and tell you the current turn around time for the rebuilds.