You could test by simply screwing the die in just a bit and see if it bumps the shoulder back more, fwiw. It should cam over a little harder and bump the shoulders a bit more.
Skip's Shims
- Thread starter K22
- Start date
DShortt
Gold $$ Contributor
My press doesn't cam over. I don't see how that would matter but I've been wrong before.
WSnyder
Silver $$ Contributor
If my setup will not allow for enough sizing I’ll take a touch off the end of the die to add clearance. You could do the same and take some off the top of your shellholder. Since I use the Redding comp shellholders I’ll take it off the die if I need clearance.
Btw I have a feeling there’s some miscommunication going on in this thread and subsequent arguing has ensued.
My sincere apologies sir for my misunderstanding.
muleystalker
Silver $$ Contributor
Not really directed at you but I can see how it might look that way and I'm sorry for that. I know you aren't him, just trying to lighten things up a little. These days over half the people on this sight haven't even been around long enough to know who he is, just a little inside joke for some of the members that have been around for a while . LOL
On another note I think I see where you might be having a disconnect with this whole setting up the die with shims. When guys say they are setting up say with a .010" shim from the start that means they are doing a regular die set up, bottoming out on the shell holder, then they lock the die ring in place, remove the die and install a .010" shim and try a piece of brass then measur. If they need more bump then they reduce the amount of shim as needed. Buy doing it this way it eliminates potentially ruining a piece a brass by over bumping it as could be the case by bottoming out the die on the shell holder and sizing a piece of brass. Hope this helps you understand better as I think this may be where you where having a disconnect with the shim setup.
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DShortt
Gold $$ Contributor
And I completely understand that. The OP of this thread either doesn't set his up that way or he did a very bad job of explaining it.
AlNyhus
Silver $$ Contributor
For your first time working with them, stacking .020-.030 will give you more room to experiment and get a feel for it. -Al
I believe the confusion lies in this paragraph-
Fourth, if you set up your FL die properly with the shims, you can change the amount of bump simply by replacing the shim. There are different methods to set up the FL die with them. For me, setting up with the .010" work better for ME since it gives me a wide range of bump options by using one of the thinner shims in the set which range from .008 down to .003. Set up this way, the shell holder is always in contact with the die. You never have to change the lock ring of the die to make a sizing adjustment.
A picture or two of the “set up” may clairlfy this for readers.
Thx
Fourth, if you set up your FL die properly with the shims, you can change the amount of bump simply by replacing the shim. There are different methods to set up the FL die with them. For me, setting up with the .010" work better for ME since it gives me a wide range of bump options by using one of the thinner shims in the set which range from .008 down to .003. Set up this way, the shell holder is always in contact with the die. You never have to change the lock ring of the die to make a sizing adjustment.
A picture or two of the “set up” may clairlfy this for readers.
Thx
I had used shims the same way, but for a different purpose. I have 4 bolt action 8MM Mauser rifles and I used the shims so I could use a single die to properly size the brass for each rifle w/o having to reset the die each time I wanted to reload. I tried the witness mark idea, but I could not get that to work well enough for me. The shims worked perfectly. As the years went on I was fortunate enough to have the funds to buy each rifle its own die.
I suggest you move on. Use other method. Skip Shims are not the only method; others work equally well perhaps even better for some. I merely offered it as an inexpensive alternative. I've explained the process in detail and don't have any more that I can offer.
I'm sorry I can post a picture; I've never been able to successfully to that. However, I don't understand how a picture of a shim under the lock rings is going to clarify its use. I don't see how posting a picture of a measurement with a bump gauge before and after that clearly show the shoulder has been bumped by using a thinner shim after the initial setup is going to clarify the issue.
You seem to have a problem understanding that if a FL die is turned down beyond contact with the shell holder that the case will receive more sizing. If you read the standard instructions by RCBS for setting up a FL die you will see that they tell you to screw the die down 1/8 to 1/4 turn from where the die contacts the shell holder. This creates a "cam over" condition and increases the sizing. Most of us know that is not a good practice because it results in too much sizing that's why bump gauges are used to set the FL die to a lessor cam over condition to produce the optimum sizing for that die. But the point is that turning the die down increases the sizing up to a point.
I really don't wish to debate this issue anymore.
DShortt
Gold $$ Contributor
I completely understand that, however that is not the way everyone in this thread describes how they set the die up to use the shims. At this point it's beating a dead horse anyway. I have 2 sets of shims ordered and when they arrive I will prove or disprove the described set ups to myself.
Thanks to you who have remained cordial in your replies. I appreciate candor. Insults and name calling, not so much.
marine52
Silver $$ Contributor
Good answer. I think you both are correct in some aspect.
DSHORTT is correct in that when steel is in firm contact with another piece of steel, there is no give and no room for further bump.
K22 is correct when he says that removing a shim or turning a die down a tad bit after shellholder-to-die contact will usually give more bump.
This apparent paradox is due to the “slop” in the press or the press flexing under pressure. The press has many links made of different materials and additional pressure is sometimes needed to guarantee max shoulder bump. Of course, it depends on the press. I would not expect this flex to be a factor in a Prazipress or the new Zero.
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BoydAllen
Gold $$ Contributor
Here is a little story that may increase the understanding of some who have posted here. Going on 30 years back I had a .220 Swift and a RCBS, one piece FL sizing die. The chamber was in a factory Savage barrel, and I have it on good authority that those dies were made to size down to SAAMI minimum spec. for loaded ammunition. In other words they changed the diameter of a fired case quite a lot, which requires more effort than one that is a close fit to a chamber. When I first set up the die, I raised the ram of my Rock Chucker to the top of its stroke and screwed the die down until it touched the shell holder, and tightened the lock ring. Then I lubed a case and ran it fully into the die, and noticed something. There was now a gap between the die and the shell holder. Curious, I got out my set of automotive feeler gauges and found the one that fit the gap. It was .006. Thinking about it for a minute, it became obvious that this was caused by linkage stretch, and that if I needed it, I had an additional .006 of down die adjustment to work with. This is why you can gain some sizing when adjusting a die, a little more toward the shell holder when it was initally set up to touch the shell holder with no case in place.....linkage stretch, or in some cases compression.
On the Skips shims, If you do an initial die setup with a .010 shim under the lock ring, and you need to change the die setting because of additional spring back from the brass becoming work hardened from repeated firings and sizing. All you have to do is to substitute a .009 shim, check the result, and if the bump is not happening or is not enough, substitute the .008 shim and so on. The initial setup with the .010 shim should be done just as if it was not there. What the shims do is give you the ability to easily make PRECISE adjustments by substituting progressively thinner shims. Doing this freehand is more difficult because of how little the die is turned to make a .001 adjustment. For those who have not done the calculation (1 divided by 14) one full turn moves the die .071".
On the Skips shims, If you do an initial die setup with a .010 shim under the lock ring, and you need to change the die setting because of additional spring back from the brass becoming work hardened from repeated firings and sizing. All you have to do is to substitute a .009 shim, check the result, and if the bump is not happening or is not enough, substitute the .008 shim and so on. The initial setup with the .010 shim should be done just as if it was not there. What the shims do is give you the ability to easily make PRECISE adjustments by substituting progressively thinner shims. Doing this freehand is more difficult because of how little the die is turned to make a .001 adjustment. For those who have not done the calculation (1 divided by 14) one full turn moves the die .071".
Thanks for clarifying what I thought was a simple concept. I was just trying to help and offer another way to manage bump, inexpensively. Apparently, I confused some members which I apologize. But I can assure, those Skip Shims work.
Conventional presses like RCBC, Redding, Lyman, etc. have inherent cam over tendencies precisely as you described because of the play in the linkages. My press in an RCBC Jr., over 50 years old. Using the Skip Shims and a bump gauge (Whidden) I can make precise bump adjustments.
BoydAllen
Gold $$ Contributor
Thanks, I did not know that he does that. I have that press. Do you remember what the work cost?
BoydAllen
Gold $$ Contributor
Your post was both timely, and well written. I wish that I could say that all of mine have been. Having spent some time in front of students explaining things, I have become acutely aware that individuals may need something explained in a different way in order that they may understand. That was all that I was trying to do.
So reading all of this if you have a press like a lee classic cast press with hard stop on linkages you can't size anymore? Since once you remove thicker shim and go to thinner shim you don't have anymore camming ability?or will the lee classic cast with hard stop still have some play to gain more sizing after hard stop on linkages and shell holder? I'm using Redding comp shell holders and thinking of ordering shims as well but want know or understand what I'm doing for sure.
Sorry to add to confusion but trying to learn as well.hate to read all of this and come away confused thx
Sorry to add to confusion but trying to learn as well.hate to read all of this and come away confused thx
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