FL Die and shoulder measuring

markwilks said:
One last question. When I first ran my brass through the FL die the shoulder came out to about 2.12 +. I then was trying to copy what my loaded Nosler ammo shoulder measured at 2.104 so I kept turning the die down till I got to about 2.105. Did I ruin those cases? Is it dangerous to reload those and risk case separation? I really don’t want to damage my new rifle. Thanks again. I’ve got a new die set coming and was hoping I can start over and take the cases I’ve only sized down to 2.12 and run them through again then call it good and not worry about the measurement of the shoulder. At most the 2.12 cases got FL sized and bumped twice.
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I haven't seen what caliber this is. But you did say belted?

I would say they are fine unless you have a REALLY long chamber.

Incipient Case head failure rarely presents in a couple of firing/sizing cycles unless your gun has serious headspace issues. Cartridge design plays a role as well. Cases with more taper and shallow shoulder angle will present faster. Think 22-250, 303 British, or 6.5x55.

There are lots of Youtubes about it which you can watch.

An experienced eye can see the shiny ring forming in front of the rim or belt long before a case actually separates. I have a coat hanger which I've bent into a probe to feel for the ring on the inside of cases. You bend it into a paper clip shape with about a 4-5" spike. Like a wire icepick. Deburr the end of the spike really well so you are not gouging the brass when you use it. Now put the last 1/8 to 3/16 of an inch of the spike in a vise and bend it to a 90° angle. Bend over enough to probe, but not so much you can't get it through the case mouth and neck. Now you have a case head separation feeler. It is very easy to feel the divet inside the case close to the web. The tool costs you nothing but 10 minutes shop time and an old coat hanger or brazing rod. You can bend the tip of an old ice pick as well if you can sneak it out of the kitchen without getting caught.

Fiber optic cameras are great for this as well. You can go as deep down this rabbit hole as you want.
 
44hunter45 said:
I haven't seen what caliber this is. But you did say belted?

I would say they are fine unless you have a REALLY long chamber.

Incipient Case head failure rarely presents in a couple of firing/sizing cycles unless your gun has serious headspace issues. Cartridge design plays a role as well. Cases with more taper and shallow shoulder angle will present faster. Think 22-250, 303 British, or 6.5x55.

There are lots of Youtubes about it which you can watch.

An experienced eye can see the shiny ring forming in front of the rim or belt long before a case actually separates. I have a coat hanger which I've bent into a probe to feel for the ring on the inside of cases. You bend it into a paper clip shape with about a 4-5" spike. Like a wire icepick. Deburr the end of the spike really well so you are not gouging the brass when you use it. Now put the last 1/8 to 3/16 of an inch of the spike in a vise and bend it to a 90° angle. Bend over enough to probe, but not so much you can't get it through the case mouth and neck. Now you have a case head separation feeler. It is very easy to feel the divet inside the case close to the web. The tool costs you nothing but 10 minutes shop time and an old coat hanger or brazing rod. You can bend the tip of an old ice pick as well if you can sneak it out of the kitchen without getting caught.

Fiber optic cameras are great for this as well. You can go as deep down this rabbit hole as you want.
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Thank you. It’s 7mm Rem Mag
 
Your brass is fine. It will fireform to your chamber like others have stated.

The reason the factory Nosler brass is so short is because the first firing the headspace is set off the belt. Once fired you are now setting it off the shoulder. It’s very common with belted cases for them to stretch that much on initial firing.

You can easily remove the stuck case also. Just drill and tap the primer pocket and mount the die in your press facing upwards. Use a socket that is larger than your die OD a washer and a bolt same thread as you threaded the pocket. Thread the bolt in and continue to thread it down using it as puller setup and pull the stuck case out.
 
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markwilks said:
Thank you. It’s 7mm Rem Mag
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That's a bummer. Belted magnums usually have a sloppy fit in chamber and shoulder dimensions can vary significantly because they headspace off the belt so shoulder dimension is less important. Because of that sloppy fit, first firing on virgin brass frequently blows the shoulder forward a lot (0.014-0.022" seems common). By trying to push that shoulder all the way back to virgin spec, you're working the brass a lot and reducing it's useful life because of all the case stretch that comes from the shoulder blowing forward multiple times. If it was not a belted magnum, the virgin brass wouldn't have stretched as much on the first firing and you wouldn't have worked it back as much to get it near virgin dimensions.

Going forward, only size such that the shoulder moves 0.002-0.003" from fired dimension and you'll probably want a willis collet die to size near the belt.
 
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Wind Gypsy said:
That's a bummer. Belted magnums usually have a sloppy fit in chamber and shoulder dimensions can vary significantly because they headspace off the belt so shoulder dimension is less important. Because of that sloppy fit, first firing on virgin brass frequently blows the shoulder forward a lot (0.014-0.022" seems common). By trying to push that shoulder all the way back to virgin spec, you're working the brass a lot and reducing it's useful life because of all the case stretch that comes from the shoulder blowing forward multiple times. If it was not a belted magnum, the virgin brass wouldn't have stretched as much on the first firing and you wouldn't have worked it back as much to get it near virgin dimensions.

Going forward, only size such that the shoulder moves 0.002-0.003" from fired dimension and you'll probably want a willis collet die to side near the belt.
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So with everyone saying just bump .002 does that mean use my neck sizing die and not the FL die after firing this batch?
 
markwilks said:
So with everyone saying just bump .002 does that mean use my neck sizing die and not the FL die after firing this batch?
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That's not what I'm saying. Use your FL sizing die, just set the locking ring so you dont size more than is necessary to reliably chamber ammo without resistance. That correlates to shoulder being pushed back 0.002 to 0.003".
 
markwilks said:
So with everyone saying just bump .002 does that mean use my neck sizing die and not the FL die after firing this batch?
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No. Just adjust your full length die so that it sizes the case just BARELY enough that you can close the bolt with no extra resistance.

Unscrew the lock ring on your die and back your die out of the press a good distance. Insert a fired case, and raise the ram as if you’re sizing. Leave the ram up(handle down). Screw the die down until it touches the case. Lower the ram(raise the handle). Screw the die down a teeny bit(1/4 turn is .018” and that’s a lot). Now size the case. Now you have a sized case. Get a fired case, put it in your gun, and close the bolt. See how that feels. Now do the same thing with the case you just sized. Continue sizing the case JUST A LITTLE MORE until you can feel that the sized case is not causing resistance when you close the bolt. If you can’t tell the difference between a sized case and a fired case, but you know you’ve moved the shoulder back, then you’re going to have to remove the firing pin, and possibly the ejector plunger.

When you know you have the die where you want it. Lock the ring down, AND CHECK AGAIN. Sometimes tightening the lock ring ends up changing things.

Since you have some cases that you oversized already, you can see if you can feel the difference between them and a fired case when you close the bolt on them. If you cannot, then you’ll need to pull the firing pin. You can do that with para chord, a shoe string, or a small Allen wrench if you don’t have the tool. Just pull the firing pin back with the string or Allen wrench and unscrew it. You’ll see why it’s nice to have the tool, but you don’t HAVE TO have the tool. If you have to remove the ejector, you can do that with a drill bit and finesse with a hammer if you don’t have punches and an arbor press.
 
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ImBillT said:
No. Just adjust your full length due so that it sizes the case just BARELY enough that you can close the bolt with no extra resistance.

Unscrew the lock ring on your die and back your did out of the press a good distance. Insert a fired case, and raise the ram as if you’re sizing. Leave the ram up(handle down). Screw the die down until it touches the case. Lower the ram(raise the handle). Screw the die down a teeny bit(1/4 turn is .018” and that’s a lot). Now size the case. Now you have a sized case. Get a fired case, put it in your gun, and close the bolt. See how that feels. Now do the same thing in the case you just sized. Continue sizing the case JUST A LITTLE MORE until you can feel that the sized case is not causing resistance when you close the bolt. If you can’t tell the difference between a sized case and a fired case, but you know you’re moved the shoulder back, then you’re going to have to remove the firing pin, and possibly the ejector plunger.

When you know you have the die where you want it. Lock the ring down, AND CHECK AGAIN. Sometimes tightening the lock ring ends up changing things.

Since you have some cases that you oversized already, you can see if you can feel the difference between them and a fired case when you close the bolt on them. If you cannot, then you’ll need to pull the firing pin. You can do that with para chord or a shoe string if you don’t have the tool. If you have to remove the ejector, you can do that with a drill bit and finesse with a hammer if you don’t have punches and an arbor press.
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Now I got it. Thank you.
 
markwilks said:
So with everyone saying just bump .002 does that mean use my neck sizing die and not the FL die after firing this batch?
Click to expand...
No, bumping the shoulder is actually FL sizing but at a bare min! You move the shoulder back at all and the whole case should get sized some little bit. If you'd take your new cases and fire them a couple times neck sizing with a FL die the case will expand to where you can't put the fired case back in the chamber and close the bolt. That's the way I go at it to make the case fit the individual chamber. When you get the case that won't chamber, simply turn the sizing die down just a bit at a time and resize till the bolt will close on the case. Some take it down till they can still feel the shoulder rubbing the chamber but I like to take it down till I can no longer feel the case rub at all. Then the case will pretty much perfectly fit in that chamber but maybe not in another. I would not personally try to match the dimentions of any factory load. They are made so they should chamber in any rifle for that cartridge. What you should end up with is a cartridge that will fit right in YOUR chamber. I had two 243's for some time and sized both this way. The cartridge's for one fit in both chambers but for the other only in one chamber. S get the sizing die set for that rifle and lock it in. If I had other rifles with two or more same cartridges I would do the same. Then each rifle would have it's own set of dies.
 
Don Fischer said:
No, bumping the shoulder is actually FL sizing but at a bare min! You move the shoulder back at all and the whole case should get sized some little bit. If you'd take your new cases and fire them a couple times neck sizing with a FL die the case will expand to where you can't put the fired case back in the chamber and close the bolt. That's the way I go at it to make the case fit the individual chamber. When you get the case that won't chamber, simply turn the sizing die down just a bit at a time and resize till the bolt will close on the case. Some take it down till they can still feel the shoulder rubbing the chamber but I like to take it down till I can no longer feel the case rub at all. Then the case will pretty much perfectly fit in that chamber but maybe not in another. I would not personally try to match the dimentions of any factory load. They are made so they should chamber in any rifle for that cartridge. What you should end up with is a cartridge that will fit right in YOUR chamber. I had two 243's for some time and sized both this way. The cartridge's for one fit in both chambers but for the other only in one chamber. S get the sizing die set for that rifle and lock it in. If I had other rifles with two or more same cartridges I would do the same. Then each rifle would have it's own set of dies.
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I’ve learned so much here. Thanks. I’ll be doing it correctly next time.
 
I think all these tools for measuring have created more problems than they will ever solve. On every cartridge, the case headspaces somewhere. On the 7mm Rem Mag it's the belt! On all belted mag's it's the belt! To make the belted mag case fit your rifles chamber well it is necessary to particial size, bump the shoulder! Best way I found on my own 7mm Mag I mentioned above. Then the case was sized to fit the chamber even if it was a sloppy chamber. Problem with belted case's is if you FL each time and the chamber is sloppy after several reloads your gonna develope head separation at the head. You can see it coming from a bright ring around the head. Couple more fireing's at most and the head will separate from the case! The fix is to never get there in the first place, size the case to fit your chamber! To neck size with a FL die, simply back the die out some and run a case through it. You'll be able to see how far down the neck you sized by simply looking at the sized case neck, stick's out boldly! You only need to size the neck down about 7mm, dia of a 7mm bullet! Couple times and the case will not chamber in your rifle even MTY! That's when you start turning the dies down to partial size the case, bump the shoulder. You'll reach a point where the fired case will chamber but you can still feel the neck rub in the chamber, go down more till you can no longer feel the neck rub. If you really have the need to get the measurement your looking for then, measure the case! It will be just short of completely filling your chamber and if what I've read in the past is true, the belted case will now headspace on the shoulder and head separation will go away!

You might get this measure everything, out of your head and simply make the case fit your chamber. Bad thing about that belt, because headspace with those cartridges is set on that belt, some chamber's are sloppy. One firing on a case will not separate the head in fact two of three won't but FL size to the belt three or four time's witth a sloppy chamber and your gonna see ring around the head. By far the easiest way to correct it that I've found is what I just told you, no big mystery! next best thing to do is sell the rifle and get a 280 Rem or a 7mm-08! both of them headspace on the shoulder! 280 and 7mm-08 are both rimless and headspace on the shoulder. But even they can benifit some from partial sizing even though most sloppy chambers go away with them.
 
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Don Fischer said:
I think all these tools for measuring have created more problems than they will ever solve. On every cartridge, the case headspaces somewhere. On the 7mm Rem Mag it's the belt! On all belted mag's it's the belt! To make the belted mag case fit your rifles chamber well it is necessary to particial size, bump the shoulder! Best way I found on my own 7mm Mag I mentioned above. Then the case was sized to fit the chamber even if it was a sloppy chamber. Problem with belted case's is if you FL each time and the chamber is sloppy after several reloads your gonna develope head separation at the head. You can see it coming from a bright ring around the head. Couple more fireing's at most and the head will separate from the case! The fix is to never get there in the first place, size the case to fit your chamber! To neck size with a FL die, simply back the die out some and run a case through it. You'll be able to see how far down the neck you sized by simply looking at the sized case neck, stick's out boldly! You only need to size the neck down about 7mm, dia of a 7mm bullet! Couple times and the case will not chamber in your rifle even MTY! That's when you start turning the dies down to partial size the case, bump the shoulder. You'll reach a point where the fired case will chamber but you can still feel the neck rub in the chamber, go down more till you can no longer feel the neck rub. If you really have the need to get the measurement your looking for then, measure the case! It will be just short of completely filling your chamber and if what I've read in the past is true, the belted case will now headspace on the shoulder and head separation will go away!

You might get this measure everything, out of your head and simply make the case fit your chamber. Bad thing about that belt, because headspace with those cartridges is set on that belt, some chamber's are sloppy. One firing on a case will not separate the head in fact two of three won't but FL size to the belt three or four time's witth a sloppy chamber and your gonna see ring around the head. By far the easiest way to correct it that I've found is what I just told you, no big mystery! next best thing to do is sell the rifle and get a 280 Rem or a 7mm-08! both of them headspace on the shoulder! 280 and 7mm-08 are both rimless and headspace on the shoulder. But even they can benifit some from partial sizing even though most sloppy chambers go away with them.
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When you’re right you’re right!
 
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