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Brass Resizing Dillema

Woodbubba

Private
Minuteman
Jan 26, 2018
29
8
Portions of the following was misposted earlier in the All Things Rimfire Forum


After three years of chasing the perfect SD and ES reloads I decided to reset my process. I have been reloading Hornady 6.5 cm brass using ELD M 140gn and Competition HPBT 140gn Hornady bullets. My RPR nodes on 2750 fps +/- so nothing exotic with my charges. Was using H4350 but have had to go to IMR 4350 with the shortages. Primers have been uniformly Federal Premium Match which now has to change but did score 1000 CCI BR4. My process up to now has been SS tumble clean, primer pocket depth and flash hole uniforming, neck resizing with a Redding Competition die set, inside/outside neck and primer pocket chamfering and priming with the Frakfort Arsenal hand primer. I switched to a Auto Trickler from a Charge Master Lite. All in all I get fair results but never ES and SD statistics in the single digits over 10 rounds measured with a LabRadar. Chasing the lands over 2500 +/- rounds has kept me sub .5 moa if I do my part. I have been consistent out to 1400 yards with capable spotting and have hit a mile on every occasion I had the opportunity.

All that said I hope to start shooting 500 yard FClass this next season. Judging from my past results on the 500 yard gong and the Labradar my ES is going to be a hurdle. I’ve tooled up to anneal every reload with an AMP Aztec Annealer and retooled with LE Wilson dies and gauges to full length resize and chamber seat with an AMP Press. Drawing from my Hornady brass which has been reloaded at most three times I started the sizing pricess as specified by the Wilson die/gauge instructions. I also have their minimum chamber gauge and micrometer set up. After running about 200 cases I have 10 that flat refuse to fit the minimum chamber gauge and produce a heavy bolt close in the gun. The Wilson gauges say the length and shoulder dimensions are good and all the measurements I know how to take of the datum and other critical dimensions show under minimum SAAMI chamber. I’ve dialogued with Wilson tech support thinking potentially I have an oversized full length die at mid body because of how the cartridge feels going into the gauge stopping the thickness of the base proud. The base end will slide into the gauge so I know its not a base diameter issue. These 10 rounds also sized heavier on the press than those that fit the min chamber gauge. Wilson has shown no interest in seeing the die nor the brass pieces suggesting I return the die to the seller for a refund.

Is there another explanation any of you reloading gurus can offer that might produce an understanding of what is going on? Is it the die or do I have some super springy brass mid body in theses 10 cartridges? I’ve not loaded any in the chamber seating die so can’t speak to how concentric the fully loaded is.
 
You have 190 cases that work and 10 that don't. You are focused on the 5% that didn't work in your new setup and not on the 95% that did work. Is this a good use of your time? I completely understand wanting to have all 200 work - you want four full 50-round boxes, all 200 worked in the old process, is there something wrong with the new gear - I get it.

I have only guesses why they didn't work. Maybe the Wilson sizer is trying to make brass that is closer to chamber size and these cases just don't size enough. Maybe the chamber reamer was worn and didn't cut enough steel. Maybe there is some effect from annealing case shoulders but not bodies?

You mentioned that the brass is too big somewhere. If you haven't already done this, take one of the "bad" cases, Magic-marker the entire thing and then chamber it until you see where the black is worn off. At least you will be sure where the problem is.

If the reamer used to make the Wilson die was made too small or worn out, it would oversize your brass and you would not have this issue. In order for the Wilson die to have this problem, their die reamer would have to be too big - unlikely but not impossible. On the other hand, if the chamber reamer was made too small or worn then you would have exactly this problem.
 
Thanks for the marker suggestion I’ll give that a shot. Us old retired OCD guys can focus on the smallest nit much like picking fly crap out of the pepper. I am about to introduce 300 new Alpha cartridges all from the same lot into the process. I’ve made so many mistakes over time I want to do my best to be totally competent with the tooling and comfortable with my understand starting this new chapter. Again thanks for your suggestion.
 
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Dan Dowling (one of the most innovative bench rest gunsmiths) used to make guns and barrels for me. He told me in order to make a gun shoot, there are only 5 things that matter - maybe it was 7 things. The problem is - there are many things, which 5 things? Everyone who does precision reloading has exactly the same problem - which things matter? When we start out and because we don't know what matters, we try to make everything perfect. Turns out, much time is wasted trying to find the 5 things - it takes a lot of shooting to figure it out and each gun (and each barrel) is a little different. Set that brass aside and try to make the good ones shoot. Come back to the problem later - or not. I reload so I can shoot, I don't shoot in order to have brass that needs to be reloaded.
 
Before proceeding to accuracy tuning one must figure out how to control brass instead of the brass controlling you.
 
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you are worried about brass for a 500 yard group and you're starting out with hornady brass. I'll just say what others are thinking...

you don't need any new equipment. you need medication.

btw, you said retired and OCD so f-class was already a given.
 
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Change the brass. Hornady brass isn't very consistent. I really never have any issues with getting my SD well into the single digits, usually under 5SD. You can almost forego most of the brass prep, especially with cleaning and primer pocket prep and still get single digit SDs. Use quality brass like Lapua, Alpha ect. I loaded up some Lapua virgin brass the other day and was getting 5SD and ES of around 15 and the only brass prep I did was the expand the neck to clean up some of the dinged up cases. Basically the same combo, 140gr ELDM, H4350, Lapua cases and Wolf Primers. Another factor not ammo related is the barrel can cause you not being able to get low chrono numbers. But if the gun shoots to your satisfaction, just roll with it. Not all loads with low numbers are the best shooting loads.
 
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I agree with the others saying to ditch Hornady. Too much prep to get it to what Lapua is right out of the box. But that's not why you wrote to the forum. It's quite possible you could switch to Lapua, get 5-6 firings in and have the same issue again.

If you've got a stiff bolt on close, you've got a brass sizing issue. Could be something at the shoulder, could be something on the body. Someone else mentioned finding a "stiff" case and covering it in Sharpie vomit. Chamber it and see where the Sharpie has been rubbed off.

If it's only just started happening, it could be due to a small chamber and your sizing die isn't appropriately sizing the body. I wouldn't think it would happen at 3 firings (when I've see this happen to me, it's been more like 5-6), but then it's Horndaddy brass, so who knows...

Sharpie first, conjecture second.
 
Dan Dowling (one of the most innovative bench rest gunsmiths) used to make guns and barrels for me. He told me in order to make a gun shoot, there are only 5 things that matter - maybe it was 7 things. The problem is - there are many things, which 5 things? Everyone who does precision reloading has exactly the same problem - which things matter? When we start out and because we don't know what matters, we try to make everything perfect. Turns out, much time is wasted trying to find the 5 things - it takes a lot of shooting to figure it out and each gun (and each barrel) is a little different. Set that brass aside and try to make the good ones shoot. Come back to the problem later - or not. I reload so I can shoot, I don't shoot in order to have brass that needs to be reloaded.
Whole heartily agree and from my limited experience three if them are consistent propellant combustion, barrel node, and seating depth. My first focus is and will continue to be safe loads. The drill with the Hornady brass is a test from fired cases to load ready cases with a new tool set. Once confident I have prepped cases that are consistently pass all the known means of assuring they are safe to load and fire I will induct the 300 new Alpha cases into the process. The 10 out of 200 in question while only 5% maybe unsafe. Extrapolating that to 1000 rounds a year is 50 chances of a potentially unsafe condition. The Sharpie test showed chamber interference in the case bodies well above the web so the Wilson min chamber gauge was correct. This seems to point directly at the full length Wilson die. Will try a friends full length Redding die soon. Again thanks for the tip.
 
Change the brass. Hornady brass isn't very consistent. I really never have any issues with getting my SD well into the single digits, usually under 5SD. You can almost forego most of the brass prep, especially with cleaning and primer pocket prep and still get single digit SDs. Use quality brass like Lapua, Alpha ect. I loaded up some Lapua virgin brass the other day and was getting 5SD and ES of around 15 and the only brass prep I did was the expand the neck to clean up some of the dinged up cases. Basically the same combo, 140gr ELDM, H4350, Lapua cases and Wolf Primers. Another factor not ammo related is the barrel can cause you not being able to get low chrono numbers. But if the gun shoots to your satisfaction, just roll with it. Not all loads with low numbers are the best shooting loads.
That is my plan. 300 new Alpha cases all from the same lot waiting in the wings once I am confident with the new tooling and its use. The Hornady brass all came from factory loads, mostly American Gunner. Got my money’s worth minus the consistency I think I need so one more firing and it’s scrap just to ammortize the time spent in prep over a couple of trips to the range. Thanks for your insights.
 
I agree with the others saying to ditch Hornady. Too much prep to get it to what Lapua is right out of the box. But that's not why you wrote to the forum. It's quite possible you could switch to Lapua, get 5-6 firings in and have the same issue again.

If you've got a stiff bolt on close, you've got a brass sizing issue. Could be something at the shoulder, could be something on the body. Someone else mentioned finding a "stiff" case and covering it in Sharpie vomit. Chamber it and see where the Sharpie has been rubbed off.

If it's only just started happening, it could be due to a small chamber and your sizing die isn't appropriately sizing the body. I wouldn't think it would happen at 3 firings (when I've see this happen to me, it's been more like 5-6), but then it's Horndaddy brass, so who knows...

Sharpie first, conjecture second.
Sharpie test showed chamber rub mid body on the case well into the area that should have been sized. The min chamber gauge was accurate. Points at the Wilson die. Will try a friend‘s Redding in a few days to see if indications change. Only other logical explanation seems to be some really springy brass. Thanks for the input.
 
Sounds like a case lube problem
Considered that but ruled it out when the heavy press also showed sizing issues in the gauge and now with a Sharpie test in the gun. The ten in question were all lubed exactly the same as the other 190 so ruling out case lube.
 
you are worried about brass for a 500 yard group and you're starting out with hornady brass. I'll just say what others are thinking...

you don't need any new equipment. you need medication.

btw, you said retired and OCD so f-class was already a given.
The Hornady brass is serving to prove my process produces safe rounds first. I have new Alpha brass to use once I am confident I understand what I’m attempting and can do it consistently. 10 out of 200 extrapolates to 50 out of 1000 chances to need medication or medical attention from an unsafe condition going bad. Trying hard to avoid needing medication😬
 
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The OP said he neck sizes.
Nowhere did he mention any body sizing.

Size those 10 cases with a full length die and you will see that they need it, including the other 190.

If you are having to lightly crush the brass to chamber them, it's gonna cause you issues during competition.


For the issue of ES/SD, I won't use Hornady brass for >1k shooting.
I've had too many instances of unexplainable verticle when using it.
Use Lapua and it goes away.

The Lapua is better in every respect, including its ability to keep ES/SD low.

It's more consistent in weight which translates to better numbers.
Shoot them side by side (at 800 yds or more) with the Hornady brass and you'll see the verticle is much better with good brass.

It shows up at shorter ranges, but it's much easier to see further out.
 
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I agree with the others saying to ditch Hornady. Too much prep to get it to what Lapua is right out of the box. But that's not why you wrote to the forum. It's quite possible you could switch to Lapua, get 5-6 firings in and have the same issue again.

If you've got a stiff bolt on close, you've got a brass sizing issue. Could be something at the shoulder, could be something on the body. Someone else mentioned finding a "stiff" case and covering it in Sharpie vomit. Chamber it and see where the Sharpie has been rubbed off.

If it's only just started happening, it could be due to a small chamber and your sizing die isn't appropriately sizing the body. I wouldn't think it would happen at 3 firings (when I've see this happen to me, it's been more like 5-6), but then it's Horndaddy brass, so who knows...

Sharpie first, conjecture second.
Sharpie showed chamber interference mid-case. The min chamber gauge was accurate pointing to the Wilson die. Will try a friend’s Redding die to see in a few days. I have 300 new Alpha cases on deck once I know I am producing safe to load and shoot cases. Thanks for your insights.
 
Okay, I see where the OP mentioned recently buying the Wilson FL die.

Are you sure the die is set correctly?
As the die begins to squeeze the web area, it will push brass forward causing the middle to expand outward and the case shoulder will go forward until it contacts the shoulder of the die.

It's like squeezing a balloon....

Make sure your FL die is set correctly.
 
OP,
If I have any brass that sizes harder than the others, I do two things:
I leave the ram in the up position for an extra second or two.
Secondly, I lower the ram just enough to take pressure off the case body and neck (about 1/2") and then raise the ram a second time.

Give that a try
 
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The OP said he neck sizes.
Nowhere did he mention any body sizing.

Size those 10 cases with a full length die and you will see that they need it, including the other 190.

If you are having to lightly crush the brass to chamber them, it's gonna cause you issues during competition.


For the issue of ES/SD, I won't use Hornady brass for >1k shooting.
I've had too many instances of unexplainable verticle when using it.
Use Lapua and it goes away.

The Lapua is better in every respect, including its ability to keep ES/SD low.

It's more consistent in weight which translates to better numbers.
Shoot them side by side (at 800 yds or more) with the Hornady brass and you'll see the verticle is much better with good brass.

It shows up at shorter ranges, but it's much easier to see further out.
Second paragraph I say now full length sizing. Neck sizing was the old process. Full length done on all 200 now being discussed including the 10 bad players. Found chamber interference with the Sharpie test mid body on the bad cases. Points at the Wilson die. I have new Alpha brass to induct to the process once I am sure my process produces safe to load and shoot cases.
 
Okay, I see where the OP mentioned recently buying the Wilson FL die.

Are you sure the die is set correctly?
As the die begins to squeeze the web area, it will push brass forward causing the middle to expand outward and the case shoulder will go forward until it contacts the shoulder of the die.

It's like squeezing a balloon....

Make sure your FL die is set correctly.
Did that to include pre and post sizing measurement of the set back using the Wilson micrometer. Getting consistent .002-.003 reduction. 190 good 10 bad all the same process.
 
OP,
If I have any brass that sizes harder than the others, I do two things:
I leave the ram in the up position for an extra second or two.
Secondly, I lower the ram just enough to take pressure off the case body and neck (about 1/2") and then raise the ram a second time.

Give that a try
I did several times. The bad pieces have been resized at least twice and maybe more as well as the cycling of the press and rotating the case and resizing.
 
Let’s get some actual measurements in here

309E5E2A-FF87-4E75-9AEE-494BD241C2FB.jpeg
 
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If the die is not to spec why did the other 190 size just fine?

Could these 10 be highest charged ones of a ladder test?
 
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If the die is not to spec why did the other 190 size just fine?

Could these 10 be highest charged ones of a ladder test?
Don’t ladder test. Use QuickLoad to find node around 2750 then +/- .5 grains in .1 gn increments to certify mv stability. Never seen any sign of pressure problems on any of the cases used.
 
Been there see my original post and I quote “The Wilson gauges say the length and shoulder dimensions are good and all the measurements I know how to take of the datum and other critical dimensions show under minimum SAAMI chamber”
What you are telling me is that you dont know your dimensions.
 
Sharpie test sample photos showing front and back shots on the ill fitting brass.2443B26D-00E0-4DE5-A0C0-E5CFC8B65CE4.jpeg713F8028-EB07-4EEE-97EC-A54700C3A629.jpeg
 
What you are telling me is that you dont know your dimensions.
Okay, specifics. Neck sized .287
Datum to base 1.5400 under SAAMI min chamber of 1.541
Shoulder .457 again under SAAMI min chamber of .4630
Base .470 vs spec .427
OAL 1.91 vs spec. 1.925
Base .469 vs spec. .4714
Shoulder set back from unsized -.002 to -.003 using Wilson micrometer
What am I missing?
 
Okay, specifics. Neck sized .287 This seems fine for the sized down neck
Datum to base 1.5400 under SAAMI min chamber of 1.541 Doesnt matter what the "spec" is- your tool and your chamber could fall at opposite ends of the spectrum and it can still be misinterpreted as a minimum. Go with the real world numbers on the tools in front of you from fired to sized.
Shoulder .457 again under SAAMI min chamber of .4630 This seems fine
Base .470 vs spec .427 This number is fucked but .470 is probably fine
OAL 1.91 vs spec. 1.925 This doesnt matter so long as its not too long which is is but its probably not the problem. Still trim em back
Base .469 vs spec. .4714 This is ok looking but it depends on what your chamber is really, compare to fired. BUt it also doesnt jive with what you write two lines above
Shoulder set back from unsized -.002 to -.003 using Wilson micrometer Tying into the nspec nt mattering above, measure the shoulder set back from your chamber.
What am I missing?

Whats your fired vs sized, dont worry about what it is to some arbitrary saami reference. Go off of how it interfaces with your own equipment. The books dont know whats right in front of you.

That said, if its only 10 that are tough to close, Id just load and shoot them and see if they manifest themselves on the next sizing cycle. If they do and it bugs you toss em. If they dont then you know it was probably a lack of lube or something in the sizing process.
 
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Before proceeding to accuracy tuning one must figure out how to control brass instead of the brass controlling you.
Once assured my process is producing safe to load and shoot brass I will be confident in taking control.
 
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Whole heartily agree and from my limited experience three if them are consistent propellant combustion, barrel node, and seating depth. My first focus is and will continue to be safe loads. The drill with the Hornady brass is a test from fired cases to load ready cases with a new tool set. Once confident I have prepped cases that are consistently pass all the known means of assuring they are safe to load and fire I will induct the 300 new Alpha cases into the process. The 10 out of 200 in question while only 5% maybe unsafe. Extrapolating that to 1000 rounds a year is 50 chances of a potentially unsafe condition. The Sharpie test showed chamber interference in the case bodies well above the web so the Wilson min chamber gauge was correct. This seems to point directly at the full length Wilson die. Will try a friends full length Redding die soon. Again thanks for the tip.
What safety risk do you think exists in this case? How do you think the brass will fail and how might you or someone else be injured by that failure?

I don't think that your 10 cases are unsafe. If that was my brass I would shoot them or toss them depending on how much brass I had and my investment in those specific pieces of brass but based on everything said so far safety would not be a concern.
 
I agree with the others saying to ditch Hornady. Too much prep to get it to what Lapua is right out of the box. But that's not why you wrote to the forum. It's quite possible you could switch to Lapua, get 5-6 firings in and have the same issue again.

If you've got a stiff bolt on close, you've got a brass sizing issue. Could be something at the shoulder, could be something on the body. Someone else mentioned finding a "stiff" case and covering it in Sharpie vomit. Chamber it and see where the Sharpie has been rubbed off.

If it's only just started happening, it could be due to a small chamber and your sizing die isn't appropriately sizing the body. I wouldn't think it would happen at 3 firings (when I've see this happen to me, it's been more like 5-6), but then it's Horndaddy brass, so who knows...

Sharpie first, conjecture second.
sheridan slotted case gauges have saved my bacon several times.
 
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Portions of the following was misposted earlier in the All Things Rimfire Forum


After three years of chasing the perfect SD and ES reloads I decided to reset my process. I have been reloading Hornady 6.5 cm brass using ELD M 140gn and Competition HPBT 140gn Hornady bullets. My RPR nodes on 2750 fps +/- so nothing exotic with my charges. Was using H4350 but have had to go to IMR 4350 with the shortages. Primers have been uniformly Federal Premium Match which now has to change but did score 1000 CCI BR4. My process up to now has been SS tumble clean, primer pocket depth and flash hole uniforming, neck resizing with a Redding Competition die set, inside/outside neck and primer pocket chamfering and priming with the Frakfort Arsenal hand primer. I switched to a Auto Trickler from a Charge Master Lite. All in all I get fair results but never ES and SD statistics in the single digits over 10 rounds measured with a LabRadar. Chasing the lands over 2500 +/- rounds has kept me sub .5 moa if I do my part. I have been consistent out to 1400 yards with capable spotting and have hit a mile on every occasion I had the opportunity.

All that said I hope to start shooting 500 yard FClass this next season. Judging from my past results on the 500 yard gong and the Labradar my ES is going to be a hurdle. I’ve tooled up to anneal every reload with an AMP Aztec Annealer and retooled with LE Wilson dies and gauges to full length resize and chamber seat with an AMP Press. Drawing from my Hornady brass which has been reloaded at most three times I started the sizing pricess as specified by the Wilson die/gauge instructions. I also have their minimum chamber gauge and micrometer set up. After running about 200 cases I have 10 that flat refuse to fit the minimum chamber gauge and produce a heavy bolt close in the gun. The Wilson gauges say the length and shoulder dimensions are good and all the measurements I know how to take of the datum and other critical dimensions show under minimum SAAMI chamber. I’ve dialogued with Wilson tech support thinking potentially I have an oversized full length die at mid body because of how the cartridge feels going into the gauge stopping the thickness of the base proud. The base end will slide into the gauge so I know its not a base diameter issue. These 10 rounds also sized heavier on the press than those that fit the min chamber gauge. Wilson has shown no interest in seeing the die nor the brass pieces suggesting I return the die to the seller for a refund.

Is there another explanation any of you reloading gurus can offer that might produce an understanding of what is going on? Is it the die or do I have some super springy brass mid body in theses 10 cartridges? I’ve not loaded any in the chamber seating die so can’t speak to how concentric the fully loaded is.
Have you tried a Sheridan slotted gauge so you can see exactly how your round fits in a chamber? I have 5 of them in different calibers, and they have saved me a BUNCH of time.
 
Have you tried a Sheridan slotted gauge so you can see exactly how your round fits in a chamber? I have 5 of them in different calibers, and they have saved me a BUNCH of time.
Interesting comment. How did the gauge save time? I checked their site and I see pictures. Seems like I would need to drop the round into the gauge, then lay a straight-edge on the base to see which step I was on. I have similar Wilson gauges and they seem - not helpful. What am I missing?
 
Interesting comment. How did the gauge save time? I checked their site and I see pictures. Seems like I would need to drop the round into the gauge, then lay a straight-edge on the base to see which step I was on. I have similar Wilson gauges and they seem - not helpful. What am I missing?
You can actually see inside via the slot instead of blindly just finding that the base doesn’t go in.

Actually measuring is still better.
 
Interesting comment. How did the gauge save time? I checked their site and I see pictures. Seems like I would need to drop the round into the gauge, then lay a straight-edge on the base to see which step I was on. I have similar Wilson gauges and they seem - not helpful. What am I missing?
The slotted gauge allows you to see the shoulder in proper contact with the chamber as well as proper base/length specs. I don't know of any other gauge that lets you see the case as it fits in the chamber.
 
You can actually see inside via the slot instead of blindly just finding that the base doesn’t go in.

Actually measuring is still better.
Okay. That makes sense. Without the cutout, you can't be sure that it stops because of the shoulder or because of something else - say, neck too long? Is that right?

Here is how I approach that problem. In order to set up my sizing die, I use the Hornady headspace tool. My .308 cases should be 1.624 using the tool. When I think I have my sizing die set up correctly, I strip my bolt and try the case in the actual chamber. If the tool says 1.623 or 1.624, the bolt handle usually drops freely. If the tool says 1.625, the bolt handle may drop freely or it may slow at the bottom of its drop. Before I get to this point in my process I know that my brass is not too long and that the body diameter is such that the only thing stopping the bolt drop is headspace between bolt face and shoulder. It takes a couple minutes to strip and reassemble the bolt. I have the correct tools and a supply of roll pins for the ejector. In the past I have used the RCBS precision mic tools - they work too.

Process details: the lock ring on my sizing die is in a fixed position. When I begin sizing, I put a 0.010 shim under the lock ring then torque the die into the press. Measure a fired case with the Hornady tool - it will probably say 1.626 to 1.628. Lube and size a case. Wipe off the lube (lube has dimension) and check the length with the Hornady gauge, if too long, use a thinner shim - today my go-to shim is usually 0.007, this usually works. Using a fresh case each time repeat until I get 1.624. Then I check with the stripped bolt. When I think I have it right, I size three cases and check all three with the stripped bolt. If that works out, I go back and resize all of the trial cases then run the batch. I rarely have more than 5 trial cases. Once in a while I use not enough shim and I end up with a case that is too short. A couple thou doesn't matter on steel or paper. This is a fussy process but it yields repeatable results and I am just a frog hair short of chamber length. If I choose to go .002 shorter than chamber length, I just use a thinner shim.
 
Okay. That makes sense. Without the cutout, you can't be sure that it stops because of the shoulder or because of something else - say, neck too long? Is that right?

Here is how I approach that problem. In order to set up my sizing die, I use the Hornady headspace tool. My .308 cases should be 1.624 using the tool. When I think I have my sizing die set up correctly, I strip my bolt and try the case in the actual chamber. If the tool says 1.623 or 1.624, the bolt handle usually drops freely. If the tool says 1.625, the bolt handle may drop freely or it may slow at the bottom of its drop. Before I get to this point in my process I know that my brass is not too long and that the body diameter is such that the only thing stopping the bolt drop is headspace between bolt face and shoulder. It takes a couple minutes to strip and reassemble the bolt. I have the correct tools and a supply of roll pins for the ejector. In the past I have used the RCBS precision mic tools - they work too.

Process details: the lock ring on my sizing die is in a fixed position. When I begin sizing, I put a 0.010 shim under the lock ring then torque the die into the press. Measure a fired case with the Hornady tool - it will probably say 1.626 to 1.628. Lube and size a case. Wipe off the lube (lube has dimension) and check the length with the Hornady gauge, if too long, use a thinner shim - today my go-to shim is usually 0.007, this usually works. Using a fresh case each time repeat until I get 1.624. Then I check with the stripped bolt. When I think I have it right, I size three cases and check all three with the stripped bolt. If that works out, I go back and resize all of the trial cases then run the batch. I rarely have more than 5 trial cases. Once in a while I use not enough shim and I end up with a case that is too short. A couple thou doesn't matter on steel or paper. This is a fussy process but it yields repeatable results and I am just a frog hair short of chamber length. If I choose to go .002 shorter than chamber length, I just use a thinner shim.
I realize the Sheridan case gauge is not for everyone. I use it because I know if a case passes, the round will smoothly load and eject from any gun I put it in, and I can check several in the time it takes to set up and check one using the Hornady tool. Go-No Go - if it drops in and drops out, it is good to go. It's just one more tool in the tool box. The big thing is the ability to see pretty much the entire case, as it goes into the chamber and verify a good shoulder fit. It has been very helpful in troubleshooting problems. Since using them, there is one caveat - The base must be free of damage from firing or sizing or the case will not go in all the way. I turn the case over and insert it backwards. If the base doesn't go in freely, there is a ding or something on the base (or not concentric) that must be cleaned up or the case will not insert in the gauge all the way.
 
Ditch the shitty brass, don't wet tumble, the only chamber gauge you should be using is the one in the rifle unless you have one cut with the same reamer. Take out the firing pin and ejector and find shoulder bump
 
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