Question/Help resizing die on dillon 550

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Question for your guys on setup. I have a rl550b, using a standard 38/357 sizing die (dillon), resizing some cases. I have always in the past, threaded in the sizing die half way, raised up the ram all the way, then screwed in the sizing die till it hits the shellplate, then back off die 1/4 turn or abouts. Doing this sizes the entire case (or close to, minus shoulder).

Question is should I be turning/backing off the sizing die more or less? Is there a standard practice? Like 1/8th turn off, 1/2 turn off. I haven't put any feeler gauges in to see what the gap is, but it is darn close to shoulder without bowing the shell plate upon resize.

Pointers, advice? Hope that makes sense. :banghead:
 
For straight walled cases, I turn the die down to kiss the shellplate. Under the stress of sizing it won't touch.
 
The risk is breaking the carbide ring in the bottom of the die. So it depends on how far up into the die the carbide is set. I learned here to use a sheet of paper as a clearance gauge. You want the shell holder as close as it can get without touching.
 
I've been running two Dillon 550B's for over 20 years and feel qualified to answer your question. Since you are using Dillon pistol dies and all Dillon Pistol dies have carbide inserts in the sizer die, you need to use some caution in setting your sizer die since carbide is very hard and also brittle. I always set my die to touch the shell plate and back it off at least a quarter turn so that the die does not touch the carrier plate with a case fully inserted. The die lock ring should then be locked in place and you're good to go.
 
Backing off 1/4 shouldn't be a problem- 38/357 isn't as picky for the "bulge" (some cartridges require the die to be close to or touching the shellplate with the caution mentioned above regarding carbide dies...). Personally I don't worry if a carbide die is screwed down to "touch" the shellplate, but don't screw it in further.
 
Reloaders do not know how to index a die with 14 threads per per inch so they use a guesstimate in fractional turn of an inch 1/8, 1/4, 1/2 etc., 14 divided into 1 inch = .07142 per turn, I make no guesstimates, I use the companion tool to the press, the feeler gage and all my shell holders have a deck height of .125 meaning the bottom of the case does not get sized, added to that is the radius at the bottom of the die.

I am sure all the different methods for adjusting the die to the press is required because of the difference in presses, presses that deflect, flex, bend etc., none of my presses have those problems therefore I adjust the gap between the shell holder and bottom of the die in thousands with the companion tool to the press, a .001 thousands gap is = to 1/71 turn of the die with 14 threads per turn, a 1/4 turn is .017 thousands, no surprise to me after making those kind of adjustments the case after sizing will not allow the bolt to close.

I do have gaps that are seriously wide when forming cases, even then I use a standard or a feeler gage.

1/8 of a turn is .0088, all of my work is done with less than a .008 thousands gap with one exception, a M1917 Eddystone, the gap between the shell holder and bottom of the die when sizing cases for that chamber is .009 thousands, the chamber for that rifle has .016 head space.

F. Guffey
 
...it is darn close to shoulder without bowing the shell plate upon resize.

"Shoulder" is used to describe bottleneck cases, I believe. I'm going to assume you mean getting near the head of the case if you're talking about .38 Spl/.357 Magnum dies.

The 550B (and perhaps other progressive presses) have the added complication of how high the shell plate is above the shell plate platform. If the center bolt isn't adjusted correctly, rimless cases can end up being supported by the shell plate instead of the platform.

Rimmed cases don't have this problem, but the case won't travel as far as it was intended if the shell plate is too high. The shell plate platform will stop when the shell plate contacts the die.

(Another problem that can occur with a loose shell plate is crooked primers.)

So, I believe your answer is in two parts -

1. Adjust the shell plate correctly. The Dillon manual says to
Tighten with the supplied Allen wrench to the point where you are unable to turn the sprocket by hand. Now, back off the bolt slightly, allowing you to push the sprocket easily with your thumb, Fig. 9. There should be no looseness or slop at this point and when you rotate the plate, you should
be able to feel and hear the index ball “click” into place under the shellplate.


Many 550B users back off the bolt more than "slightly", and the shell plate is too loose.

2. Regarding the sizing die (for Dillon pistol dies), the manual says to
Adjust the sizing die by screwing the die body down until it contacts the shellplate and snug the lock ring.

There is no mention of backing off 1/8 turn, so I'm not sure what your source was for that.

At any rate, I believe you will have no trouble if you follow the above steps. First adjust the shell plate, then adjust the resizing die.
 
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