Yet another shoulder bump question

[J.d. Popkes]

Ahh yes..camover..
Had that with a Hornady Lock-n-Load press. Drove me crazy till I realized what was going on.

Cam over

Hard contact

Whatever the press design allows.

 

[K22]

Still’ shims won’t help if more sizing is required beyond hard contact, I turn a few thou off the shell holder…My dies have threads and I know how to use a wrench, I have a feeler gage to measure in .001 increments up or down. It’s not that complicated. If I size to bolt fall it’s always touchy whereas if I create a couple thou headspace beyond bolt fall I don’t have issues when cycling rounds before and after ignition.

The shims I am discussing are Skip Shims - they are specifically made for reloading. They are circular, have a 7/8" ID and fit snugly under the lock ring. These are NOT feeler gauges. Take a look at Sinclair's / Brownell's web site.

If your FL is setup with solid contact with the holder using the .010 shim, then replacing that shim with a .008" increase the sizing approximately .002; a 006" shim increases the sizing approximately .004, etc. I say approximately because you have to measure the fire case first, size the case with the thickness shim and measure the size case then, if necessary, try and thinner shim until to obtain the amount sizing you want. Record the shim number for future reference and you set for that group of cases, dedicated to that rifle.

The set of shims are .010, 008, 007, 006, 005, 004, 003 which provide a large range of sizing options.

 

[Lone Hunter]

Look at post #23. I put a link up describing Skip‘s Shims. They tell you about them.

 

[JFrank]

The shims I am discussing are Skip Shims - they are specifically made for reloading. They are circular, have a 7/8" ID and fit snugly under the lock ring. These are NOT feeler gauges. Take a look at Sinclair's / Brownell's web site.

If your FL is setup with solid contact with the holder using the .010 shim, then replacing that shim with a .008" increase the sizing approximately .002; a 006" shim increases the sizing approximately .004, etc. I say approximately because you have to measure the fire case first, size the case with the thickness shim and measure the size case then, if necessary, try and thinner shim until to obtain the amount sizing you want. Record the shim number for future reference and you set for that group of cases, dedicated to that rifle.

The set of shims are .010, 008, 007, 006, 005, 004, 003 which provide a large range of sizing options.

Yes I’m familiar with skips shims and agree with you 100% although we maybe discussing opposite ends of the rope.

 

[marine52]

If you read DLT’s (OP) posts, he is concerned with an inconsistent bump. He has a .010” gap between the shellholder and die when he hits his optimal base-to-datum point of 1.448 to 1.449. It was suggested by several others that he should use the Redding comp Shellholders to get a firm die-to-shellholder contact (or camover if you please) This normally leads to a more consistent bump. Area 419‘s modular shellholder system does the same thing.

Skip’s shims are a fast and precise way of adjusting your die without having to unlock the lock ring. They do not change the bump measurement given you have a hard contact between die and shellholder.

 

[K22]

Skip’s shims are a fast and precise way of adjusting your die without having to unlock the lock ring. They do not change the bump measurement given you have a hard contact between die and shellholder.

With all due respect, this is NOT true.

If the FL die is setup* with the .010 shim, then replacing the .010 shim with the thinner shims, i.e., .008 to .003 increases the bump. I've been doing this for many years now. I had no problem whatever ever obtaining any desired bump I need by inserting the appropriate shim under the lock ring.

*See my early post on setting up the FL die with the .010 shim.

 

[DShortt]

If you set your die to be in hard contact with the shell holder it can not go any closer to the shell holder.
If you add shims under the lock ring you can DECREASE the amount of shoulder set back but not INCREASE the amount of setback.
If you set your die up with a .010" shim under it and have hard contact with the shell holder then removing the .010" shim and installing a .008" shim can not increase the amount of shoulder set back. If you're doing that and your shoulder set back is changing it's simply because you sized the brass a second time and has nothing to do with the shim thickness.

 

[K22]

If you set your die to be in hard contact with the shell holder it can not go any closer to the shell holder.
If you add shims under the lock ring you can DECREASE the amount of shoulder set back but not INCREASE the amount of setback.
If you set your die up with a .010" shim under it and have hard contact with the shell holder then removing the .010" shim and installing a .008" shim can not increase the amount of shoulder set back. If you're doing that and your shoulder set back is changing it's simply because you sized the brass a second time and has nothing to do with the shim thickness.

We are pissing in the wind. I DO NOT size the cases a second time.

The FL die is set up with the .010 shim. By replacing that shim with a thinner shim, it moves the die down increasing the sizing.

I run the case through the FL die only once. Unless my bump gauge and caliper are lying, I'm bumping the shoulder back, the degree depends on the shim I'm using. It has everything to do with the shim thickness. I can create anywhere from a zero bump to a .004 bump simply by replacing the shim.

I've done this thousands of times. I verify the bump every time I size a group of cases with a bump gauge and caliper.

Have you ever used them?

 

[JFrank]

After my encounters with Mr. Guffey, I felt I was crystal clear on how to create headspace and the use of Skips shims to adjust a dies or the absence of the same.
Q- how can adding .010 ( separating the base of the die in relationship to the shell holder) then incrementally subtracting that same .010 or less decrease the length of a die/ sh combination ?

 

[243winxb]

a hornady set I bought first for this rifle acts like the neck is going to get ripped off the case.

Brass comes with a donut at neck shoulder junction on most all 223/5.56 brands. Some worse then others. Over working the necks will result in splits or separations.
A bushing die or neck turning reduces the effect to pull an expander up out of the case. Lube inside of neck.

Press linkage makes the variation when shoulder bumping. Normal .

 

[DShortt]

We are pissing in the wind. I DO NOT size the cases a second time.

The FL die is set up with the .010 shim. By replacing that shim with a thinner shim, it moves the die down increasing the sizing.

I run the case through the FL die only once. Unless my bump gauge and caliper are lying, I'm bumping the shoulder back, the degree depends on the shim I'm using. It has everything to do with the shim thickness. I can create anywhere from a zero bump to a .004 bump simply by replacing the shim.

I've done this thousands of times. I verify the bump every time I size a group of cases with a bump gauge and caliper.

Have you ever used them?

I don't use them because I set my dies differently and have no need for them.
I have been thinking about this and there is a possible explanation. If you initially set your die to hard contact with the shell holder and lock the lock ring then remove it, add a .010" shim and then begin adjusting the shims to achieve the shoulder measurement you are looking for then THAT would make sense.
If that is what you do then either I missed it or it wasn't explained that way. If it was me then I apologize.

 

[Ccrider]

Posts like this further reinforce my investment into the area 419 zero press and shellholders.

I like nice toys too. I can hold about the same level of accuracy with my Lee press and custom dies. I can also induce .001 variance with lube or not pulling the ram consistently. (Something sounds wrong about that-pulling the ram???)

The op is complaining about .001 variance in shoulder length, and he is annealing with a torch?

My suggestion is to bump all shoulders to give a minimum .002 clearance. If you have a stubborn piece, adjust the die or spin the case in the holder a half turn and size it again. No big deal. I can give several other things that I have found can cause variations on sizing but will not.

Be more concerned with whether that stubborn piece hits where it should on the target. If it does not, chunk it and move on.

 

[K22]

I don't use them because I set my dies differently and have no need for them.
I have been thinking about this and there is a possible explanation. If you initially set your die to hard contact with the shell holder and lock the lock ring then remove it, add a .010" shim and then begin adjusting the shims to achieve the shoulder measurement you are looking for then THAT would make sense.
If that is what you do then either I missed it or it wasn't explained that way. If it was me then I apologize.

No need to apologize.

The .010 shim setup provides the baseline. By replacing the .010 shim with a thinner shim the sizing is increased since you are reducing the distance between the shell holder and the die. It is sort of the same principle as competition shell holders.

I've been doing it this way for a very long time. For me, this process is easier to control bump than other methods. I'm not saying it's better, it's just easier for me, and a lot cheaper I may add. I merely offered the idea to the OP as an economical alternative to competition shell holders. The shim set can be used with any 7/8" sizing die.

 

[DShortt]

No need to apologize.

The .010 shim setup provides the baseline. By replacing the .010 shim with a thinner shim the sizing is increased since you are reducing the distance between the shell holder and the die. It is sort of the same principle as competition shell holders.

I've been doing it this way for a very long time. For me, this process is easier to control bump than other methods. I'm not saying it's better, it's just easier for me, and a lot cheaper I may add. I merely offered the idea to the OP as an economical alternative to competition shell holders. The shim set can be used with any 7/8" sizing die.

OK, you have said the exact same thing several times but I still don't understand specifically how the die is set in relation to the shell holder, when you tighten down the lock ring and when the shims are installed.

I *think* I know how this has to be done. But Lord knows I've been wrong before.

If my explanation in post #111 is flawed please explain. If that's correct then thank you for your patience.

 

[K22]

OK, you have said the exact same thing several times but I still don't understand specifically how the die is set in relation to the shell holder, when you tighten down the lock ring and when the shims are installed.

I *think* I know how this has to be done. But Lord knows I've been wrong before.

If my explanation in post #111 is flawed please explain. If that's correct then thank you for your patience.

Ok, let me try again -

1. Loosen the lock ring.

2. Place the shim you desire to be your baseline under the lock ring. I like the .010 shim because it provides me a greater range of bump.**

3. Screw the die down until it makes full contact with the shell holder. Remove all flex from the press by manipulating the die and ram until a solid contact is achieve.

4. Screw the lock ring down and lock into place with the baseline shim underneath. Use a sharpie to add a memory mark on the die body and lock ring just in case the lock ring loosens when you remove the die so you can realign.

5. The lock ring is now set and should never have to be changed. You are now set at your baseline. To increasing the amount of sizing, simply replace the .010 shim with a thinner shim. Record the shim number on the cartridge box that gives you the optimum sizing for that rifle and batch of cases for future use.

PS: Some like to choose another baseline, such as the .006 shim in which case they can increase or decrease the amount of sizing simply by replacing the .006 shim with a thicker or thinner shim.

 

[DShortt]

Ok, let me try again -

1. Loosen the lock ring.

2. Place the shim you desire to be your baseline under the lock ring. I like the .010 shim because it provides me a greater range of bump.**

3. Screw the die down until it makes full contact with the shell holder. Remove all flex from the press by manipulating the die and ram until a solid contact is achieve.

4. Screw the lock ring down and lock into place with the baseline shim underneath. Use a sharpie to add a memory mark on the die body and lock ring just in case the lock ring loosens when you remove the die so you can realign.

5. The lock ring is now set and should never have to be changed. You are now set at your baseline. To increasing the amount of sizing, simply replace the .010 shim with a thinner shim. Record the shim number on the cartridge box that gives you the optimum sizing for that rifle and batch of cases for future use.

PS: Some like to choose another baseline, such as the .006 shim in which case they can increase or decrease the amount of sizing simply by replacing the .006 shim with a thicker or thinner shim.

Someone help me out here.

If your die is tight against the shell holder you can't size the case any further. All you are doing by removing the .010" shim and replacing it with an .008" shim is changing the point at which the press arm moves by .002".

If you've done that before and sized the case again and it's now shorter than it was when checked with a comparator it's simply because you sized it a second time.

 

[K22]

Someone help me out here.

If your die is tight against the shell holder you can't size the case any further. All you are doing by removing the .010" shim and replacing it with an .008" shim is changing the point at which the press arm moves by .002".

If you've done that before and sized the case again and it's now shorter than it was when checked with a comparator it's simply because you sized it a second time.

No, I don't size it a second time once the appropriate shim for that rifle and batch of cases has been determine.

Last night I sized 20 cases for my Tikka 223 using shim .006 to push the shoulder back .001" The case were sized once, only once during this operation.

 

[DShortt]

No, I don't size it a second time once the appropriate shim for that rifle and batch of cases has been determine.

Last night I sized 20 cases for my Tikka 223 using shim .006 to push the shoulder back .001" The case were sized once, only once during this operation.

I think it's mostly a definition difference and that our methods of die setup aren't conducive.
I appreciate your patience and I'm glad your process works well for you. At the end of the day that's all that matters.

 

[BoydAllen]

If a fully formed & fired case will easily rechamber; why is it customary to bump the shoulder back at all?

The reason that we bump shoulders is to create clearance if cases are tight. If they chamber freely, there is no need....BUT cases may vary in how many firings it takes to become tight, so when you are making this determination it is a good idea to measure a good sampling of cases, after you have tried one, that is not tight. You can simply measure it and look for those that might be longer from datum to head, and then try it in your rifle. When I have time, I fire a single case until it becomes solidly tight (taking care that my rifle's lugs are properly greased) and then use that measurement as a reference for setting my die. If I have to work with once fired cases I set the die to exactly reproduce the same datum to head dimension as a once fired case, and then try it in the rifle. Most of the time it will chamber freely.

 

[JFrank]

No, I don't size it a second time once the appropriate shim for that rifle and batch of cases has been determine.

Last night I sized 20 cases for my Tikka 223 using shim .006 to push the shoulder back .001" The case were sized once, only once during this operation.

I read that as the chamber being .005 longer than the die shell holder combination.