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Misfires

Jcalder

Jcalder

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Had some misfires today. First I've had in a rifle that's got my stumped, but I think I know the issue. Just wanting to confirm.

Recently had some loaded that I want gonna use in a different rifle. Sold that rifle and decided I wasn't gonna use that powder in the new rifle so I broke everything down. I DID NOT resize my brass and I think that's where I went wrong, but I'll continue on. When I reloaded the brass I noticed I could potentially push the bullet in by hand. It was kinda hard to do, and in my mind it was fine. When to chrony the loads today doing my development routine. First one chambered hard. Didn't think much of it and touched it off. Misfire. Pull the shell out and looked it over. Put it back in the rifle and it went. Next one was tight but sent fine. Third one was tight and I started scratching my head. All my notes show the headspace in new gun is the same as the old gun based on fired cases. I had set my bullets .020 off the lands. Why are they tight?!? Touched it off and another misfire. Pulled it out and the bullet stayed in the barrel. That ended my mission right there. I took everything in and pulled my loads, resized the brass and started over.

Couple things that should be known….. The brass is 270 FC brass converted to 25-06. Annealed afterward. Possibly over annealed and soft, but I don't know. Basically I hit it for about 5 seconds with a torch being spun in a socket. I kinda think that when I pulled the bullets initially I didn't have the neck tension I should have had. But could the brass have pushed my bullets out if the base of the bullet was above the shoulder/neck intersection? Powder is imr 4955. I know it's discontinued, but I have nearly 5 pounds. That's enough to spend time on making a load.



So my question boils down to is the lack of neck tension why I had the misfires, or is it something else.
 
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I anneal before sizing so the brass works easier and doesn't spring back. Annealing after sizing doesn't really do anything except make the brass soft for the next time you size it.


My money is on poor neck tension.
 
I can't see neck tension having anything to do with the primer not going off. Did the ones that didn't fire have an obvious solid primer strike? Since the brass is converted, I would probably measure the shoulder with a comparator on both a piece of the fired brass and one of your unfired rounds. As for the rounds not going off, I'd be cautious and make sure the shoulder is not well short of a factory 25-06 round. If it's short enough, it could be moving forward when the firing pin hits it, which would possibly not let the round fire. There is also a chance that the shoulder deformed a bit when you converted the brass, which could make it feel like a long round when you chamber it. Obviously you know that at least one round was seated long. It's an interesting problem for sure.
 
Cant see how it could be anything other than either the primers or a light primer strike. If the bolt is hard to close it could be distorting the bolt just enough to make the firing pin make contact with the bolt face, either stopping it or slowing it down enough not to pop the primer.

Theoretically you could jam an overexpanded case with bullet jammed into the lands and it will still pop off if you can get the bolt to close…. Potentially with catastrophic results, but it should fire
 
nso123 said:
I can't see neck tension having anything to do with the primer not going off. Did the ones that didn't fire have an obvious solid primer strike? Since the brass is converted, I would probably measure the shoulder with a comparator on both a piece of the fired brass and one of your unfired rounds. As for the rounds not going off, I'd be cautious and make sure the shoulder is not well short of a factory 25-06 round. If it's short enough, it could be moving forward when the firing pin hits it, which would possibly not let the round fire. There is also a chance that the shoulder deformed a bit when you converted the brass, which could make it feel like a long round when you chamber it. Obviously you know that at least one round was seated long. It's an interesting problem for sure.
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I agree 100%. I've fired primed cases without a bullet without issue. Measured the headspace and I'm within .005 of factory new brass. All my brass within .005. So I'm stumped there. All rounds had obvious primer strike. This picture is of the last one, which I did not attempt to fire again.
EBF205EC-4949-4855-B2A0-F85548A93261.jpeg
 
Jcalder said:
Cci large rifle. Probably shot 600 thru the brick at this point
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CCI is normally GTG, so it shouldn't be that. The strike looks decent, but hard to tell by the pic, optical illusion makes it seem there is a large indentation and then the strike. There are a few threads online of this issue, but fixes vary, from springs, to bad primers. Do you have a different rifle to test them in?
 
Just to be sure, I'd disassemble the bolt and check the pin and spring...pin for potentially being broken, and spring and pin for grit and/or grease buildup. Even a new one can have to be cleaned sometimes. ;) Keep us updated on this one.
 
Btw, I have had this issue before, but it was bad primers, and it was Remington LR Bench primers, just a bad batch as I had 10 misfires in the first 20 or so rounds. I switched over to CCI LR primers and haven't had a misfire since.
 
Omega said:
CCI is normally GTG, so it shouldn't be that. The strike looks decent, but hard to tell by the pic, optical illusion makes it seem there is a large indentation and then the strike. There are a few threads online of this issue, but fixes vary, from springs, to bad primers. Do you have a different rifle to test them in?
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Those primers have probably been shot in 5 different rifles.

I do agree with an indent. My first thought was I didn't seat the primers all the way so I rechecked them once I got back to the bench but they're good.
 
This is a firing pin strike issue.

Something has worked its way into the firing pin channel. That is where you get the double indentation look. The firing pin IS NOT retracting all the way because something is stopping it from doing so (dirt-grit). The obstruction is small and hard. You have to take things apart and clean them.

The hard bolt closure is indicative of an overlong condition. You know this because one bullet was stuck in the rifling. I have had this with lots of calibers because I like 007 as my jump. I make a slight mistake.....or the neck tension is bad.....you get what you got.

BTW, when I have to unload a live round I put the brass in the fired bucket, put the bullet back in the box, and toss the powder. That brass goes through a complete case prep cycle, just as if it was fired.
 
DaveB said:
This is a firing pin strike issue.

Something has worked its way into the firing pin channel. That is where you get the double indentation look. The firing pin IS NOT retracting all the way because something is stopping it from doing so (dirt-grit). The obstruction is small and hard. You have to take things apart and clean them.

The hard bolt closure is indicative of an overlong condition. You know this because one bullet was stuck in the rifling. I have had this with lots of calibers because I like 007 as my jump. I make a slight mistake.....or the neck tension is bad.....you get what you got.

BTW, when I have to unload a live round I put the brass in the fired bucket, put the bullet back in the box, and toss the powder. That brass goes through a complete case prep cycle, just as if it was fired.
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I did take all the rounds and broke them down, and resized afterward. I'll disassemble the bolt and make sure something hasn't happened internally.
 
Jcalder said:
I did take all the rounds and broke them down, and resized afterward. I'll disassemble the bolt and make sure something hasn't happened internally.
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When you insert a bullet into the brass it expands the neck. Some people are kind of sensitive to this tension. Mr. B and TiminTN come to mind because in what they do every opportunity for perfection must be hunted down and conquered. My BIL shoots a 222 and is a tension junkie. How many people you know mike the expander ball?
 
DaveB said:
When you insert a bullet into the brass it expands the neck. Some people are kind of sensitive to this tension. Mr. B and TiminTN come to mind because in what they do every opportunity for perfection must be hunted down and conquered. My BIL shoots a 222 and is a tension junkie. How many people you know mike the expander ball?
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I have, but not for the purpose of neck tension lol.
 
It's rare, but there are times when the firing pin does not have enough travel before it hits the primer the impact is softened.
Think of it this way. If you punch someone from 8 inches away and then from 2 feet away which punch do you think will hit harder?
Difficult to chamber brass might be oversized enough to prevent it from fully entering the chamber.
 

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