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Skip's Shims

I watched that video. So set the die to make full contact with the shell holder, size a case and check the cartridge base to datum line, or thereabouts, with a comparator. Add shims to reduce shoulder setback if needed. Fine. I get that.

Now, what are these guys doing who start out with .010" or more shims in place to start with? How exactly are they setting up their die?
They are just working backwards, from the method you stated above, so they don't bump a shoulder back too far setting it up, they size a case and measure then remove a shim as needed until they get the bump they want. The only thing the shims are doing is taking the place of screwing the die up or down in the press and having to loosen and tighten the lock ring, the shims are just easier and quicker.
 
They are just working backwards, from the method you stated above, so they don't bump a shoulder back too far setting it up, they size a case and measure then remove a shim as needed until they get the bump they want. The only thing the shims are doing is taking the place of screwing the die up or down in the press and having to loosen and tighten the lock ring, the shims are just easier and quicker.
Well said. Thanks
 
They are just working backwards, from the method you stated above, so they don't bump a shoulder back too far setting it up, they size a case and measure then remove a shim as needed until they get the bump they want. The only thing the shims are doing is taking the place of screwing the die up or down in the press and having to loosen and tighten the lock ring, the shims are just easier and quicker.
Right, and I understand that. But if you put shims in then adjust the die to contact how is removing one or more shims going to change anything? It's steel on steel BEFORE any shims are removed.

That's what I've been trying to get across. Either I don't understand specifically how they are setting up their dies or there's just some sort of Spontaneous Serendipity going on.
 
You can do all of the above and deal with the challenges of trying to make small changes to sizing, or you can do the following. I’ve used this method for about 30 years and have yet to find a reason not to like it. I have a witness mark on the bushing, and take a fine tip Sharpie marker and put a dot on the die threads. The die is kept in place by a piece of modeling clay. Before someone protests the clay trick, I will point out that I have never had a die move in all the tens of thousands of cases sized with this setup. I can make changes to shoulder bump less than the ability to accurately measure with calipers quite easily.
 

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You can do all of the above and deal with the challenges of trying to make small changes to sizing, or you can do the following. I’ve used this method for about 30 years and have yet to find a reason not to like it. I have a witness mark on the bushing, and take a fine tip Sharpie marker and put a dot on the die threads. The die is kept in place by a piece of modeling clay. Before someone protests the clay trick, I will point out that I have never had a die move in all the tens of thousands of cases sized with this setup. I can make changes to shoulder bump less than the ability to accurately measure with calipers quite easily.
German Salazar, a competitive rifle shooter, used "witness" marks quite successfully to make sizing adjustments. Just another effective way to "skin the old cat." Good job.
 
So, I don't see the purpose of the clay. Aren't you simply adjusting the die in or out to get your exact bump? For me shims provide repeatability and a good reference for your notes. I think we all started with the witness marks but left us wanting something better.
You still use the lock ring to hold the die in place , don't you?
 
There’s 2 camps. One that make hard contact between die/shell holders, and one that doesn’t. If you’re in the no contact camp shims are for adjusting your die/bump. If you’re in the contact camp, Redding comp shell holders.

I’m 100% in the hard contact/Redding comp shell holder camp. Because I like all my bumps to be exact every time. :D
 
There’s 2 camps. One that make hard contact between die/shell holders, and one that doesn’t. If you’re in the no contact camp shims are for adjusting your die/bump. If you’re in the contact camp, Redding comp shell holders.

I’m 100% in the hard contact/Redding comp shell holder camp. Because I like all my bumps to be exact every time. :D
Shims have the same effect as the comp shell holders.
 
Right, and I understand that. But if you put shims in then adjust the die to contact how is removing one or more shims going to change anything? It's steel on steel BEFORE any shims are removed.

That's what I've been trying to get across. Either I don't understand specifically how they are setting up their dies or there's just some sort of Spontaneous Serendipity going on.
Just try it. Then figure out why it works. Lol!
 
Shims have the same effect as the comp shell holders.
I disagree. I have a set of Skips shims and they do work for their intended purpose. They allow you to change the shoulder bump w/o moving the lock ring on the die and they allow you to do this in a very precise way. In fact, Tony Boyer—winner of 12 World BR championships—describes, in his book, how to use them starting at .015” of shims and working in the direction of bump increase.
HOWEVER, YOU STILL HAVE TO SCREW THE DIE DOWN TO THE EXACT SAME POSITION TO ACHIEVE THE SAME BUMP AS IF YOU DID NOT HAVE THE SHIMS. Their use does not guarantee a hard solid contact between shellholder and die.

The Comp Shellholders sold by Redding and the modular Shellholders sold by Area 419 are totally different. The standard shellholder has a .125” distance between the surface that the case base sits on and the top of the shellholder ledge. Comp shellholders allow this distance to vary in order to maintain a solid die-to-shellholder contact. For example, the +10 shellholder has this distance at .135” , allowing a solid die-to-shellholder contact but providing 0.010” less bump.
 
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Shims have the same effect as the comp shell holders.
Comps are great & Shims are great until the chamber is shorter than the die shell holder combo. ( beyond solid contact) then you have hard cam over or reduce the SH ht or shave the die base.
I’ve also set up my dies with a .010 feeler gage between the SH and die base then simply adjust my way down incrementally until my headspace is created or I hit bottom and decide to take a few thou off the shell holder with a belt sander. Lol
 
Shims have the same effect as the comp shell holders.
There is another benefit to the Redding Competition shell holders that gets overlooked in some discussions. Within their range, they allow you to have some toggle, when your situation does not result in die contact with a standard shell holder. This toggle tends to reduce the effect of variable linkage stretch or compression (depending on the design of the particular press), which gives more uniform shoulder bump.
 
So, I don't see the purpose of the clay. Aren't you simply adjusting the die in or out to get your exact bump? For me shims provide repeatability and a good reference for your notes. I think we all started with the witness marks but left us wanting something better.
You still use the lock ring to hold the die in place , don't you?
The clay keeps the die from rotating in the bushing. You can see another piece of clay on the opposite side of the die. At one time I used 2 lumps of clay, but quickly discovered that one would keep the die in place without fail. I do not have any lock rings on any of my dies, and haven't used any in probably 30 years. It's far easier to adjust for small changes without the ring. I used lock rings for 20 years or so, but once I started using this method I never even considered going back to them. No need for any shims or graduated shell holders or any other work around method. If I want to increase or decrease shoulder bump .0005 it take about 3 seconds to do it, and do it with great accuracy.
The irony of this whole thing is that the title to this thread is "Skips Shims." The refers to Skip Otto, who I bought the press in the photo from (as well as 5 more just like it) which is a RCBS A2.
 
The clay keeps the die from rotating in the bushing. You can see another piece of clay on the opposite side of the die. At one time I used 2 lumps of clay, but quickly discovered that one would keep the die in place without fail. I do not have any lock rings on any of my dies, and haven't used any in probably 30 years. It's far easier to adjust for small changes without the ring. I used lock rings for 20 years or so, but once I started using this method I never even considered going back to them. No need for any shims or graduated shell holders or any other work around method. If I want to increase or decrease shoulder bump .0005 it take about 3 seconds to do it, and do it with great accuracy.
The irony of this whole thing is that the title to this thread is "Skips Shims." The refers to Skip Otto, who I bought the press in the photo from (as well as 5 more just like it) which is a RCBS A2.
So you are taking the "floating" concept to the extreme? I just don't feel comfy watching the die wiggle during sizing. But if it worked well for you for 30 years -who am I to argue.
 
So you are taking the "floating" concept to the extreme? I just don't feel comfy watching the die wiggle during sizing. But if it worked well for you for 30 years -who am I to argue.
Think about this for a moment if you will. With a lock ring, the die is pulled up so that both load bearing thread surfaces in the die and press are in full contact. Without a lock ring, no sizing occurs until both load bearing surfaces of the threads are in full contact with each other. There is no difference in the function of the die with or without the ring. It's just infinitely quicker, simpler, less expensive, and just as accurate to adjust without the ring.
 
I disagree. I have a set of Skips shims and they do work for their intended purpose. They allow you to change the shoulder bump w/o moving the lock ring on the die and they allow you to do this in a very precise way. In fact, Tony Boyer—winner of 12 World BR championships—describes, in his book, how to use them starting at .015” of shims and working in the direction of bump increase.
HOWEVER, YOU STILL HAVE TO SCREW THE DIE DOWN TO THE EXACT SAME POSITION TO ACHIEVE THE SAME BUMP AS IF YOU DID NOT HAVE THE SHIMS. Their use does not guarantee a hard solid contact between shellholder and die.

The Comp Shellholders sold by Redding and the modular Shellholders sold by Area 419 are totally different. The standard shellholder has a .125” distance between the surface that the case base sits on and the top of the shellholder ledge. Comp shellholders allow this distance to vary in order to maintain a solid die-to-shellholder contact. For example, the +10 shellholder has this distance at .135” , allowing a solid die-to-shellholder contact but providing 0.010” less bump.
You can explain it for them but you can’t understand it for them.
 

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