boisblancboy
New member
I am about to start reloading my .204, what are the signs of over pressure?
Over pressure signs
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boisblancboy
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I guess I should have mentioned this will be the first reloading I have done other than shotgun.
CatShooter
New member
Originally Posted By: boisblancboyI am about to start reloading my .204, what are the signs of over pressure?
Excessive pressure (not "over pressure") shows it self in this order.
First Primers crater - you are not in "Big trouble" yet, but you are approaching dangerous ground and need to quit and cut back. Look at your test loads and don't go over the last case that didn't show cratering.
Next is difficult extraction - you are getting in deep here when the bolt is hard to open..
Next is difficult extraction - with marks (wiping/smearing) on the case head from the ejector hole... you are getting in way over your head - quit while you still have a head!
If you are stupid enough to keep on going after seeing these signs, you have no business hand loading.
Split necks have absolutely nothing to do with excessive pressure.
Excessive pressure (not "over pressure") shows it self in this order.
First Primers crater - you are not in "Big trouble" yet, but you are approaching dangerous ground and need to quit and cut back. Look at your test loads and don't go over the last case that didn't show cratering.
Next is difficult extraction - you are getting in deep here when the bolt is hard to open..
Next is difficult extraction - with marks (wiping/smearing) on the case head from the ejector hole... you are getting in way over your head - quit while you still have a head!
If you are stupid enough to keep on going after seeing these signs, you have no business hand loading.
Split necks have absolutely nothing to do with excessive pressure.
venatic
Active member
I will add that it is a good idea to shoot a factory load and look at the primer to see how it looks and then as you work up your loads keep a factory handy for comparison. This will help you learn what to look for keeping in mind that different brands of primers can show pressure signs at varying rates but when pressures get high they all get flattened and then crater.
Originally Posted By: CatShooterOriginally Posted By: boisblancboyI am about to start reloading my .204, what are the signs of over pressure?
Excessive pressure (not "over pressure") shows it self in this order.
First Primers crater - you are not in "Big trouble" yet, but you are approaching dangerous ground and need to quit and cut back. Look at your test loads and don't go over the last case that didn't show cratering.
Next is difficult extraction - you are getting in deep here when the bolt is hard to open..
Next is difficult extraction - with marks (wiping/smearing) on the case head from the ejector hole... you are getting in way over your head - quit while you still have a head!
If you are stupid to keep on going after seeing these signs, you have no business hand loading.
Split necks have absolutely nothing to do with excessive pressure.
CatShooter's summary is right on. As soon as I start getting primers that are cratering, I back off!
Excessive pressure (not "over pressure") shows it self in this order.
First Primers crater - you are not in "Big trouble" yet, but you are approaching dangerous ground and need to quit and cut back. Look at your test loads and don't go over the last case that didn't show cratering.
Next is difficult extraction - you are getting in deep here when the bolt is hard to open..
Next is difficult extraction - with marks (wiping/smearing) on the case head from the ejector hole... you are getting in way over your head - quit while you still have a head!
If you are stupid to keep on going after seeing these signs, you have no business hand loading.
Split necks have absolutely nothing to do with excessive pressure.
CatShooter's summary is right on. As soon as I start getting primers that are cratering, I back off!
boisblancboy
New member
I have noticed significant cratering of the primers on the factory ammo, Hornady 32gr V-max.
venatic
Active member
That is the reason I brought that up. You more than likely have an oversized firing pin hole which lets the primer flow a little around the firing pin if I am explaining that correctly. That is NOT a sign of excessive pressure. I have had a couple of Remingtons that were like that.
As you work up your load watch for the primer getting flatter and loosing the rounded edge it has or maybe I should say stop before you loose that rounded edge.
Found this hope it is helpful. You can find anything on You Tube I guess.
As you work up your load watch for the primer getting flatter and loosing the rounded edge it has or maybe I should say stop before you loose that rounded edge.
Found this hope it is helpful. You can find anything on You Tube I guess.
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CatShooter
New member
Originally Posted By: venaticThat is the reason I brought that up. You more than likely have an oversized firing pin hole which lets the primer flow a little around the firing pin if I am explaining that correctly. That is NOT a sign of excessive pressure. I have had a couple of Remingtons that were like that.
As you work up your load watch for the primer getting flatter and loosing the rounded edge it has or maybe I should say stop before you loose that rounded edge.
Found this hope it is helpful. You can find anything on You Tube I guess.
The problems with this video is that he is using bad examples - in the beginning, he shows two .220 Swift case and says the one on the left has high pressure. It does not - that case had headspace, (it doesn't after firing)... the case on the right has serious excessive pressure, and cratered primer, but no flattened primer - that is because flattened primers are not signs of excessive pressure.
As you work up your load watch for the primer getting flatter and loosing the rounded edge it has or maybe I should say stop before you loose that rounded edge.
Found this hope it is helpful. You can find anything on You Tube I guess.
The problems with this video is that he is using bad examples - in the beginning, he shows two .220 Swift case and says the one on the left has high pressure. It does not - that case had headspace, (it doesn't after firing)... the case on the right has serious excessive pressure, and cratered primer, but no flattened primer - that is because flattened primers are not signs of excessive pressure.
To an extent, I agree with what has been said. I tend to place the least emphasis on primer cratering for the reasons mentioned above. In addition, some primers (and individual lots of primers) are soft, further complicating things. I tend to place the most emphasis on brass longevity. With properly annealed and properly sized brass (i.e. don’t un-necessarily bump the shoulder); I like to see my brass last about 9-12 loading. With some low pressure loads, I can stretch that out to 13+ loadings. These are generalizations however, because some firearms are simply harder on brass. Springy actions are very tough on brass.
venatic
Active member
Catshooter that's interesting and I think I will take this opportunity to learn something. If using the two cases say in the video and both were fire formed previously and just neck sized would a primer that looks flattened like the one on the left be a sign of pressure? That would take the excessive head space out of the equation. OR are you saying never pay any attention to the flattening of primers just watch for cratering and sticky bolt and or swipes on cases.
I do agree with John(pcammo) that I watch my properly sized cases and if I am getting 9 or more loadings without the primer pockets loosening then I am OK. I get exactly 9 from my 17 Remington loads OTOH my .221 FB brass lasts forever with what the book says is a max load.
I would guess TC Encore's fall under the springy actions because I have had a couple of issues with brass with them.
I do agree with John(pcammo) that I watch my properly sized cases and if I am getting 9 or more loadings without the primer pockets loosening then I am OK. I get exactly 9 from my 17 Remington loads OTOH my .221 FB brass lasts forever with what the book says is a max load.
I would guess TC Encore's fall under the springy actions because I have had a couple of issues with brass with them.
ARCOREY
New member
I'm glad you asked this Venatic. I just recently noticed flat primers in my 243 on near max listed loads. I had just full length sized the brass and was hoping it was due to them not being fire formed and neck sized. I hadn't noticed this in the past with hotter loads when I was neck sizing only.
I've seen Federal primers 'crater' and winchester primers, with the same load were fine. Now what do I do?
For one I don't shoot the Fed primers in that load anymore. The load doesn't stick the bolt, with either primer. And it's accurate.
So, is a cratered or flat primer ALWAYS a excessive pressure sign?? I am not trying to be a smart azz, I'm trying to learn.
For one I don't shoot the Fed primers in that load anymore. The load doesn't stick the bolt, with either primer. And it's accurate.
So, is a cratered or flat primer ALWAYS a excessive pressure sign?? I am not trying to be a smart azz, I'm trying to learn.
CatShooter
New member
Originally Posted By: venaticCatShooter that's interesting and I think I will take this opportunity to learn something. If using the two cases say in the video and both were fire formed previously and just neck sized would a primer that looks flattened like the one on the left be a sign of pressure? That would take the excessive head space out of the equation. OR are you saying never pay any attention to the flattening of primers just watch for cratering and sticky bolt and or swipes on cases.
I do agree with John(pcammo) that I watch my properly sized cases and if I am getting 9 or more loadings without the primer pockets loosening then I am OK. I get exactly 9 from my 17 Remington loads OTOH my .221 FB brass lasts forever with what the book says is a max load.
I would guess TC Encore's fall under the springy actions because I have had a couple of issues with brass with them.
That's a good example. Say you have a bunch of cases that were factory loads and shot in your gun. They should have 0.000" to 0.002" headspace (none for practical purposes).
Now you load up a bunch of test loads. As the loads get higher and higher, there is more pressure on the cup of the primer - and it's natural desire is to expand out to fill any space, until it is touching the bolt face, and pocket walls, 100%.
Remember that the primer cup is only 0.020" to 0.025" thick, and the metal is not very hard. So as pressure grows, it starts to loose that "round edge" look, and starts to have a little flat look.
This is normal. As pressure continues to rise, the primer will continue to loose that round look and the flat area will get slightly larger.
Now... as long at the primer is not oozing back into the pin hole, every thing is fine. This just the natural result of the pressure on the insides of the primer.
When the primer cup, just under the pin, starts going back into the hole by pushing the pin back, then you are at the ragged edge. If it continues to push until the part of the cup under the pin, gets forced back into the bolt face... then the case pressure will flow back into the bolt, and that is a very badd thing. That is why there are holes on the sides of bolts (or some other means of letting the gas escape).
Now... at one time (when gun companies only hired guy people to work there), you never had pin holes larger than the pin itself - by maybe 0.001" to 0.002".
But for maybe the last 20 or so years, (due to the CNC machines turning out 1,000,000 parts a second, without individual inspection, some are going to be too large or too small. )...
... Remingtons (and some others) have been coming out with some firing pin holes that are ~10 to 12 thou larger than the pin. This allows the primer to flow back a little - but it does this with almost any pressure - even wimpy factory loads. These "flow craters" look different than true "pressure craters"... they have soft edges and look rounded.
True pressure cratering has sharp outside edges and a straight wall on the outside, and the pin dent looks shallower than normal.
These are the reasons that a beginner should always shoot a few factory loads (preferably Remington or Winchester, but not Federal) - you need to know what a "normal" primer looks like on your rifle.
The weak place in the whole cartridge system is the primer and the firing pin, firing pin hole, and spring. Those are the only things that keep the whole damm thing from coming apart.
In large rifle, all the cups are 0.025" to 0.027".
But in small rifle primers, the Federal, CCI 400, and Rem 6-1/2 are 20 thou, and the Rem 7-1/2, the Win SR, the CCI 450 and BR-4 are all 25 thou... so they can hold 25% to 35% more pressure before cratering (or flatting).
Way back when, people used to think the Fed primer was hotter, because it would crater on loads that would not with Rem 7-1/2, Win SR, and BR-4, etc... but it turned out that it was the wimpy cup on the Federal primer that was the cause of the cratering.
To answer your question more directly... don't worry about flattening, as long as the primer dent looks OK
If this doesn't make sense, tell me and I will try it again.
---
Originally Posted By: pahntr760I've seen Federal primers 'crater' and winchester primers, with the same load were fine. Now what do I do?
Stop using Federal primers
Quote: For one I don't shoot the Fed primers in that load anymore. The load doesn't stick the bolt, with either primer. And it's accurate.
So, is a cratered or flat primer ALWAYS a excessive pressure sign??
The Fed primer is thin and soft, which is why it would crater, but there were no other signs - I have 3,000+ Fed SR primers that I have had for maybe 15 yers that I might use in a 22 Hornet or .218 Bee... but I would never use them in a cartridge like a 223.
A flat primer is not a sign of pressure - a VERY flattened primer is a sign of excess head space.
A truly cratered primer is a sign of excess pressure for that primer] - if you have a load that is cratering Federal primers, it might be a 48Kpsia load - but with that primer, it is a shakie load cuz a little more, even though the pressure is not high, the Fed primer can let go into the action - whereas, a Remington 7-1/2 or a CCI BR-4 will hold 55-60Kpsia and not crater, in the same rifle.
The amount of pressure is not a concern of the modern rifle - the modern rifle will not come apart at 100,000 psi - it is the primer - pin - and spring, that are the determining factors. The rifle can take whatever you throw at it.
.
I do agree with John(pcammo) that I watch my properly sized cases and if I am getting 9 or more loadings without the primer pockets loosening then I am OK. I get exactly 9 from my 17 Remington loads OTOH my .221 FB brass lasts forever with what the book says is a max load.
I would guess TC Encore's fall under the springy actions because I have had a couple of issues with brass with them.
That's a good example. Say you have a bunch of cases that were factory loads and shot in your gun. They should have 0.000" to 0.002" headspace (none for practical purposes).
Now you load up a bunch of test loads. As the loads get higher and higher, there is more pressure on the cup of the primer - and it's natural desire is to expand out to fill any space, until it is touching the bolt face, and pocket walls, 100%.
Remember that the primer cup is only 0.020" to 0.025" thick, and the metal is not very hard. So as pressure grows, it starts to loose that "round edge" look, and starts to have a little flat look.
This is normal. As pressure continues to rise, the primer will continue to loose that round look and the flat area will get slightly larger.
Now... as long at the primer is not oozing back into the pin hole, every thing is fine. This just the natural result of the pressure on the insides of the primer.
When the primer cup, just under the pin, starts going back into the hole by pushing the pin back, then you are at the ragged edge. If it continues to push until the part of the cup under the pin, gets forced back into the bolt face... then the case pressure will flow back into the bolt, and that is a very badd thing. That is why there are holes on the sides of bolts (or some other means of letting the gas escape).
Now... at one time (when gun companies only hired guy people to work there), you never had pin holes larger than the pin itself - by maybe 0.001" to 0.002".
But for maybe the last 20 or so years, (due to the CNC machines turning out 1,000,000 parts a second, without individual inspection, some are going to be too large or too small. )...
... Remingtons (and some others) have been coming out with some firing pin holes that are ~10 to 12 thou larger than the pin. This allows the primer to flow back a little - but it does this with almost any pressure - even wimpy factory loads. These "flow craters" look different than true "pressure craters"... they have soft edges and look rounded.
True pressure cratering has sharp outside edges and a straight wall on the outside, and the pin dent looks shallower than normal.
These are the reasons that a beginner should always shoot a few factory loads (preferably Remington or Winchester, but not Federal) - you need to know what a "normal" primer looks like on your rifle.
The weak place in the whole cartridge system is the primer and the firing pin, firing pin hole, and spring. Those are the only things that keep the whole damm thing from coming apart.
In large rifle, all the cups are 0.025" to 0.027".
But in small rifle primers, the Federal, CCI 400, and Rem 6-1/2 are 20 thou, and the Rem 7-1/2, the Win SR, the CCI 450 and BR-4 are all 25 thou... so they can hold 25% to 35% more pressure before cratering (or flatting).
Way back when, people used to think the Fed primer was hotter, because it would crater on loads that would not with Rem 7-1/2, Win SR, and BR-4, etc... but it turned out that it was the wimpy cup on the Federal primer that was the cause of the cratering.
To answer your question more directly... don't worry about flattening, as long as the primer dent looks OK
If this doesn't make sense, tell me and I will try it again.
---
Originally Posted By: pahntr760I've seen Federal primers 'crater' and winchester primers, with the same load were fine. Now what do I do?
Stop using Federal primers
Quote: For one I don't shoot the Fed primers in that load anymore. The load doesn't stick the bolt, with either primer. And it's accurate.
So, is a cratered or flat primer ALWAYS a excessive pressure sign??
The Fed primer is thin and soft, which is why it would crater, but there were no other signs - I have 3,000+ Fed SR primers that I have had for maybe 15 yers that I might use in a 22 Hornet or .218 Bee... but I would never use them in a cartridge like a 223.
A flat primer is not a sign of pressure - a VERY flattened primer is a sign of excess head space.
A truly cratered primer is a sign of excess pressure for that primer] - if you have a load that is cratering Federal primers, it might be a 48Kpsia load - but with that primer, it is a shakie load cuz a little more, even though the pressure is not high, the Fed primer can let go into the action - whereas, a Remington 7-1/2 or a CCI BR-4 will hold 55-60Kpsia and not crater, in the same rifle.
The amount of pressure is not a concern of the modern rifle - the modern rifle will not come apart at 100,000 psi - it is the primer - pin - and spring, that are the determining factors. The rifle can take whatever you throw at it.
.
venatic
Active member
Originally Posted By: ARCOREYI'm glad you asked this Venatic. I just recently noticed flat primers in my 243 on near max listed loads. I had just full length sized the brass and was hoping it was due to them not being fire formed and neck sized. I hadn't noticed this in the past with hotter loads when I was neck sizing only.
I would think that would be a good example of what catshooter is saying that once you set the shoulder back you in essence create some headspace and get a little primer flattening.
LOL we were typeing at the same time.
Catshooter that is a very good explanation and makes perfect sense. Thanks I think that will be helpful to a good many folks.
I would think that would be a good example of what catshooter is saying that once you set the shoulder back you in essence create some headspace and get a little primer flattening.
LOL we were typeing at the same time.
Catshooter that is a very good explanation and makes perfect sense. Thanks I think that will be helpful to a good many folks.
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CatShooter
New member
Every time you touch the shoulder with a FL or Bump die, you create headspace.
For the rifles that I use for varmints, I prefer a "Crush" feel when I close the bolt - that is a negative headspace, and cases will last forever. I have ~300 pieces of Rem 22-250 that are on their 6th barrel (maybe 10,000-12,000 firings - 40 firings each), and they are as good as when they were first fired.
.
ARCOREY
New member
Originally Posted By: CatShooter
Every time you touch the shoulder with a FL or Bump die, you create headspace.
For the rifles that I use for varmints, I prefer a "Crush" feel when I close the bolt - that is a negative headspace, and cases will last forever. I have ~300 pieces of Rem 22-250 that are on their 6th barrel (maybe 10,000-12,000 firings - 40 firings each), and they are as good as when they were first fired.
.
To make sure I understand this right because I'm on a new barrel and want to make the most of it and my brass. After fire forming my brass, I should be able to reset my FL dies or neck dies and only decap the brass and flare the mouth and and not even touch the shoulder? I try and keep my neck dies off the shoulder now and set my FL dies per Reddings recommended procedure of camming over on the shell holder. It sounds like I shouldn't ever need my FL die again after I get them fired in my chamber or for my 2 die sets, never need a neck die.
I'm also gauging my trim length with one of the neck pilots from sinclair that you soft seat in a fired case that is trimmed short. My Lapua brass doesn't seem to grow much at all in my 243. I've yet to get it to where I'm close in my old factory barrel or my new barrel of my 243. Am I listening too much to the wives tales crowd about case stretch in a 243, or am I lucky? I'm hitting atleast 5 firings and still not getting to the gauge length on any of my 200 Lapuas and only chamfer and deburred them from day one.
This has been an informative post. Thanks to all the contributors.
Every time you touch the shoulder with a FL or Bump die, you create headspace.
For the rifles that I use for varmints, I prefer a "Crush" feel when I close the bolt - that is a negative headspace, and cases will last forever. I have ~300 pieces of Rem 22-250 that are on their 6th barrel (maybe 10,000-12,000 firings - 40 firings each), and they are as good as when they were first fired.
.
To make sure I understand this right because I'm on a new barrel and want to make the most of it and my brass. After fire forming my brass, I should be able to reset my FL dies or neck dies and only decap the brass and flare the mouth and and not even touch the shoulder? I try and keep my neck dies off the shoulder now and set my FL dies per Reddings recommended procedure of camming over on the shell holder. It sounds like I shouldn't ever need my FL die again after I get them fired in my chamber or for my 2 die sets, never need a neck die.
I'm also gauging my trim length with one of the neck pilots from sinclair that you soft seat in a fired case that is trimmed short. My Lapua brass doesn't seem to grow much at all in my 243. I've yet to get it to where I'm close in my old factory barrel or my new barrel of my 243. Am I listening too much to the wives tales crowd about case stretch in a 243, or am I lucky? I'm hitting atleast 5 firings and still not getting to the gauge length on any of my 200 Lapuas and only chamfer and deburred them from day one.
This has been an informative post. Thanks to all the contributors.