Misfires

[Oldbloke]

I went camping last week. ( the foxes won. ) Checking the zero of my 223 I had 2 misfires. Changed ammo and seemed OK.
At the time I also put a few drops of oil on the fireing pin.

To follow up/check I went to the range today.
More misfires, about 1 in 6-7.
I've measured bump, a bit much, about 0.008"
I'll reduce that.

BA, Marlin xl7
6-7 years old. (Remlin)
Fired about 450 rounds.
S&B primers abt 4 yrs old, till now, no issues.
Rifle is shooting small 5 shot groups. Say,,,20mm @ 100mtrs.
Looks like a weak strike.
After the range session I've stripped the bolt, soaked/washed in kerosene (Not much gunk in there)
and lubed with transmission fluid.


I'm thinking to eliminate the excessive bump as an issue, I will just prime 20 fired cases and try them?

I'll check firing pin putrusion tomorrow.

Rifle is in very good condition.

Any ideas welcome.

[on_one_wheel]

Has your ammo been stored well or has it been left in a vehicle or hot shed and exposed to heat for an extended period of time. ?

[deye243]

And here's me thinking I'm pretty switched on what is bump.
Or are you talking about shoulder bump?

[Oldbloke]

And here's me thinking I'm pretty switched on what is bump.
Or are you talking about shoulder bump?

Yeh, shoulder bump.

[straightshooter]

For a beginner's question to be asked by such a prolific dispenser of knowledge on this shooting forum surely would tempt a nasty person to respond with 'physician heal thyself'.
Fortunately I refuse to succumb to that temptation.
However 8 thou of headspace in the cases, unknown additional headspace in the factory chamber, possibly combined with annealed shoulders and possibly military grade S&B primers not correctly bottomed in the primer pocket, the answer is kind of obvious isn't it.

[Larry]

I would suggest a reclean of the bolt and Not to put the trans fluid on it leave it dry or a small spray of Silicon lube. Also reduce the case movement by tightning up that bump.

[Oldbloke]

I would suggest a reclean of the bolt and Not to put the trans fluid on it leave it dry or a small spray of Silicon lube. Also reduce the case movement by tightning up that bump.

Hadn't thought of using silicon spray.

[Wm.Traynor]

I would suggest a reclean of the bolt and Not to put the trans fluid on it leave it dry or a small spray of Silicon lube. Also reduce the case movement by tightning up that bump.

Hadn't thought of using silicon spray.

FWIW Oldbloke, I use that stuff on my CZ trigger and it has removed the creep

[Oldbloke]

Thx.
I don't think it's the primers.
I don't think dodgy spring is likely.
Something has changed.
Either:
Too much shoulder bump.
Fireing pin dirty, fouled. (Been washed and lubed now)

I'll test the "excessive shoulder bump" theory sometime this week.

[GQshayne]

Had a misfire issue with my dads rifle last year. It is the 6th or 7th .243Win I have loaded ammo for since the 1980's, and the first one to have a probelm. Bit of a head scratch that one, and took some time to fix.

Being a new rifle to us, we eventually concluded that we had a rifle problem, as the same handloads worked well in two other rifles. But ultimately it was the handloads, not suited to the chamber of the different rifle. As an aside, I have a Belgian made FN Browning BLR that fires the ammo that the Japanese made Miroku BLR will not. Both are Pre "81 models. As hunting rifles, we never previouly bothered with too much tinkering with handloads. But we had to woth this one.

Shoulder bump, was part of the solution, but during the process we also looked closely at the primers, and found that different brands were a different size, and seated differently. One of them sat quite low in the primer pocket, which was not helping.

[Wapiti]

Gee it'd be a major reloading mistake if it was due to shoulder bump i.e too much.
If the primers are fine, no oil has been mistakenly introduced (where it should NEVER be in a die) and affected the primers, and the firearm wear and overall quality isn't suspect, even fairly sloppy cartridges should be fired completely reliably with standard firing pin protrusion.
From the OP's other posts on every other subject, one would imagine that a headspace mistake would not be the issue.

Firing pin protrusion in a rifle supposedly only firing so little cartridges, 450, could not be the issue unless the protrusion was marginal in the first place, and the quality of the spring has deteriorated from being generally poor quality or (maybe) also from storing with the bolt cocked (normal state when out of the gun and stored as per regs, unless deliberately decocked).
Any quality spring will not degrade from this, however. But who knows which subcontractor on a Friday afternoon tempered the springs.
The firing pin tip just doesn't "wear down" and get shorter, unless it's a quality issue with hardening and it shortens with peening, but only 450 rounds?


As other learned posters have suggested, checking for foreign objects and sticky old lube inside the bolt would be the first thing checked, and the easiest, but the OP has said that's been done.
Firing pin spring tension is another thing to check at the same time.

[Oldbloke]

As other learned posters have suggested, checking for foreign objects and sticky old lube inside the bolt would be the first thing checked, and the easiest, but the OP has said that's been done.
Firing pin spring tension is another thing to check at the same time.

Thx Wapiti,

Too much shoulder bump could cause the issue. But I also doubt it's enough. After all people fire form cases to magnums etc all the time.

As you have said all the other possibilities seem a stretch. All primers, ammo etc are stored In good conditions.

I'm banking its just being sticky fireing pin due to gunk. I'm yet to test again after cleaning and oiling it. But it did initially seem very clean.

Will be a day or two before I test, out of action with a chest infection now.

[GQshayne]

The issue I had was simple. As a hunter, I never had a need to do any more than the basics. I fitted dies in the press as per the manufacturers instructions and loaded ammo for decades with not one problem ever. And that is in at least 6 different rifles in the same calibre, being .243. All bolt actions and then one lever action.

But the next lever action rifle did not like it. So then for the first time ever, I had to measure how much the shoulder was being set back, and adjust the die for that individual rifle. Problem fixed. And that was after going over springs and firing pins, action timing and cleaning etc etc. So a lesson learned.

[Oldbloke]

The issue I had was simple. As a hunter, I never had a need to do any more than the basics. I fitted dies in the press as per the manufacturers instructions and loaded ammo for decades with not one problem ever. And that is in at least 6 different rifles in the same calibre, being .243. All bolt actions and then one lever action.

But the next lever action rifle did not like it. So then for the first time ever, I had to measure how much the shoulder was being set back, and adjust the die for that individual rifle. Problem fixed. And that was after going over springs and firing pins, action timing and cleaning etc etc. So a lesson learned.

Thxs GQshayne,
That's just what I'm after.
Do you recall how much shoulder bump you had that caused the misfires?

I've also remembered I had the rifle stock off about a month ago. So will take the stock off again, perhaps something there.

[GQshayne]

The issue I had was simple. As a hunter, I never had a need to do any more than the basics. I fitted dies in the press as per the manufacturers instructions and loaded ammo for decades with not one problem ever. And that is in at least 6 different rifles in the same calibre, being .243. All bolt actions and then one lever action.

But the next lever action rifle did not like it. So then for the first time ever, I had to measure how much the shoulder was being set back, and adjust the die for that individual rifle. Problem fixed. And that was after going over springs and firing pins, action timing and cleaning etc etc. So a lesson learned.

Thxs GQshayne,
That's just what I'm after.
Do you recall how much shoulder bump you had that caused the misfires?

I've also remembered I had the rifle stock off about a month ago. So will take the stock off again, perhaps something there.

Can't tell you that sorry, as I do not have the equipment to measure such things accurately. Rather than measuring it to find the issue, it was a process of elimination, and was the last thing we considered. So I used a fired case, and a cut off .22REM to put over the shoulder, and then set the die to set it back the required amount. Found the method on youtube. I think you can buy tools to do the job properly but I do not have those. Never had to do it before, so it was a learning exercise. I have just had a look to see if I had it written down, but cannot see anything.

I am sure that will disappoint many of our members!

[Oldbloke]

The issue I had was simple. As a hunter, I never had a need to do any more than the basics. I fitted dies in the press as per the manufacturers instructions and loaded ammo for decades with not one problem ever. And that is in at least 6 different rifles in the same calibre, being .243. All bolt actions and then one lever action.

But the next lever action rifle did not like it. So then for the first time ever, I had to measure how much the shoulder was being set back, and adjust the die for that individual rifle. Problem fixed. And that was after going over springs and firing pins, action timing and cleaning etc etc. So a lesson learned.

Thxs GQshayne,
That's just what I'm after.
Do you recall how much shoulder bump you had that caused the misfires?

I've also remembered I had the rifle stock off about a month ago. So will take the stock off again, perhaps something there.

Can't tell you that sorry, as I do not have the equipment to measure such things accurately. Rather than measuring it to find the issue, it was a process of elimination, and was the last thing we considered. So I used a fired case, and a cut off .22REM to put over the shoulder, and then set the die to set it back the required amount. Found the method on youtube. I think you can buy tools to do the job properly but I do not have those. Never had to do it before, so it was a learning exercise. I have just had a look to see if I had it written down, but cannot see anything.

I am sure that will disappoint many of our members!

A case works to compare. I do a similar thing. Shame you didn't write it down tho.

[Wyliecoyote]

In a perfect world excessive headspace should never occur. SAAMI is there for a reason where dies, shell holders and chambers are set to correct dimensions. Theoretically a case full length sized in quality dies where the shell holder bottoms out on the base of the die should not have more than a couple of thou headspace in a correctly set up chamber. Then comes the question of how doesn't 50 thou of firing pin protrusion not ignite a primer in a case with 10 thou headspace slop in a chamber? Surely that last 40 thou would still do the job. Well sometimes it doesn't which defies all logic. The loose cartridge, even with an ejector pushing it forward into the chamber, sometimes acts as a shock absorber leading to a weak primer strike. Again no rhyme nor reason yet it does happen.
Then there is the primer itself. I am hearing some bad feedback on primers of brands i had never heard of until the last couple of years. Similar stories to those dreaded Federal 205s from 20 years back.

[Oldbloke]

In a perfect world excessive headspace should never occur. SAAMI is there for a reason where dies, shell holders and chambers are set to correct dimensions. Theoretically a case full length sized in quality dies where the shell holder bottoms out on the base of the die should not have more than a couple of thou headspace in a correctly set up chamber. Then comes the question of how doesn't 50 thou of firing pin protrusion not ignite a primer in a case with 10 thou headspace slop in a chamber? Surely that last 40 thou would still do the job. Well sometimes it doesn't which defies all logic. The loose cartridge, even with an ejector pushing it forward into the chamber, sometimes acts as a shock absorber leading to a weak primer strike. Again no rhyme nor reason yet it does happen.
Then there is the primer itself. I am hearing some bad feedback on primers of brands i had never heard of until the last couple of years. Similar stories to those dreaded Federal 205s from 20 years back.

Close to my theory.
If the case is pushed forward, that uses up some of the energy of the pin hitting the primer. Less energy equals shallow dent.

How much is too much tho?

You can bet if it's something else it's simple.

[Larry]

Its normally a little bit of a few things combind that create issues like the one you have OB. I was having the same issue in my target rifle the one positive side affect was it was great to see if you had any flinch. never knowing if it was going to go bang or just a dry fire.

[Oldbloke]

Its normally a little bit of a few things combind that create issues like the one you have OB. I was having the same issue in my target rifle the one positive side affect was it was great to see if you had any flinch. never knowing if it was going to go bang or just a dry fire.

[animalpest]

I had an issue with new cases from an Australian manufacturer. The new cases were neck sized and the loaded with CCI primers. Some didn't fire after being loaded.

I checked the case length to shoulder and some were over 8 thou shorter on the ones that didn't fire.

A combination of excess headspace and hard primer cups caused the issue.

The primers have been used on other rifles without issue.

[Oldbloke]

I had an issue with new cases from an Australian manufacturer. The new cases were neck sized and the loaded with CCI primers. Some didn't fire after being loaded.

I checked the case length to shoulder and some were over 8 thou shorter on the ones that didn't fire.

A combination of excess headspace and hard primer cups caused the issue.

The primers have been used on other rifles without issue.

Thx animalpest,
Your confirming. 008" could be the issue

[GQshayne]

The issue I had was simple. As a hunter, I never had a need to do any more than the basics. I fitted dies in the press as per the manufacturers instructions and loaded ammo for decades with not one problem ever. And that is in at least 6 different rifles in the same calibre, being .243. All bolt actions and then one lever action.

But the next lever action rifle did not like it. So then for the first time ever, I had to measure how much the shoulder was being set back, and adjust the die for that individual rifle. Problem fixed. And that was after going over springs and firing pins, action timing and cleaning etc etc. So a lesson learned.

Thxs GQshayne,
That's just what I'm after.
Do you recall how much shoulder bump you had that caused the misfires?

I've also remembered I had the rifle stock off about a month ago. So will take the stock off again, perhaps something there.

Can't tell you that sorry, as I do not have the equipment to measure such things accurately. Rather than measuring it to find the issue, it was a process of elimination, and was the last thing we considered. So I used a fired case, and a cut off .22REM to put over the shoulder, and then set the die to set it back the required amount. Found the method on youtube. I think you can buy tools to do the job properly but I do not have those. Never had to do it before, so it was a learning exercise. I have just had a look to see if I had it written down, but cannot see anything.

I am sure that will disappoint many of our members!

A case works to compare. I do a similar thing. Shame you didn't write it down tho.

Yes. In my defence (your honour) we worked out that this BLR was the weak link, and that cases sized correctly for it will then still chamber in the other rifles. So the sizing die was marked for future use, suitable for all rifles now. The bolt actions are no doubt more tolerant of varying size reloads. I know the BLR can be timed to give different clearances depending on what tooth is engaged, and still be within spec. So there are a few factors to this.

[Oldbloke]

We all live and learn.
GMF'd how I have abt 0.008". I thought I had it at closer to 0.004". About 150 cases that size too.

[Larry]

OB try seating the proj longer so that it jams when closing the bolt. If this fixes your shorter sized cases you found the problem. If nothing changes it is not the shoulder.

[Oldbloke]

OB try seating the proj longer so that it jams when closing the bolt. If this fixes your shorter sized cases you found the problem. If nothing changes it is not the shoulder.

Thx Larry.
We think alike. Was thinking along those lines.
But I plan on loading some cases that are neck sized only. (I don't normally neck size)

It was also already on the agenda to fire form the cases if I need to. I have about 200 cast bullets that I can use.

[Jorlcrin]

Had my first Misfire in my Ruger Precision Rifle today; likely put around 2500 rounds through it to date, and the very first Misfire.

Factory Federal 150gn PowerShok factory ammo.
Loaded the next round, and it fired off just fine.
Looking at the cartridge, zero sign of a strike on the primer.

Might have to dismantle the bolt and see if I have any crud in there.
I've fed a LOT of both factory ammo and reloads through this rifle, and thats my first misfire.
Must be something going around!

[Oldbloke]

Jorlcrin,
IIRC in 51 years of hunting/shooting this is my first experience with misfires.

Must be the dreaded misfire virus.

[GQshayne]

My first exp with it was back in about 1984. Dad had abought a 94 Winchester in 30/30 for me to use instead of the humble .22LR. But it would hangfire or misfire. Local gunshop said to use it for an anchor, as it had excessive headspace. Dad took it to the now defunct Kingstion Guns in Brisbane (a cafe now when Iast saw it), and the older fella disappeared into the back of his shop for a while. When he came back, he announced it was fixed.

Dad asked how much it was to fix, after the gunsmisth told us he had adjusted the hammer spring tension. It was $5. Never misfired again.

[Larry]

Interesting GQ I was just going to post that the fix to my problem in the target rifle was the firing pin spring. Well I did that and still had issues but then I bushed the spring esentially putting more preload on it and that fixed the problem. So in the end my conclusion was there was not enough firing pin speed. the extra speed I guess increases the energy delivered to the primer.