FTF. Just making sure I know why

powdergun

powdergun

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So out today firing a few rounds.

I had 10 rounds with me and wouldn't you know it number 10 does not go off.

So here is my check list on finding out why and if anyone has any more to add all advice appreciated

1) Primer dent just like all the rest
2) brass was tight in the chamber as I was fireforming new brass with a false shoulder so not thinking head space
3) Dissasembled the round and it looks like the Primer went off a wee bit but otherwise prime pocket was clean but for a small black mark.
4) Poured out the charge and saw some clumps in the powder( oh oh sizing lube)
6) Tested the gun and the brass with an empty case and fresh Primer ( all went fine)

My conclusion was lube on the Primer or bad Primer ( Winchester magnum rifle primers)

If you can think of any other reason apply to here.
 
At our rifle range, we have a box to receive misfires. Just drop the misfires in there and they get
disposed of safely. I often clean out all the CF rifle misfires and take them home to disassemble.

Sort of an "Autopsy" I have seen several loads with the same situation as you describe. Primer
fired, but seemed to lack the brisance to actually ignite the powder, leaving some small "clumps".

I am of the opinion that there was some sort of contamination of either the primer or, possibly, the
powder. [moisture, oil, etc] In one case, it was very obvious that the powder was very damp, but
some were not so obvious.

Interesting observation. Of the "reloaded" misfires, fully 60% contained no powder!! I guess some
just do not pay enough attention while at the bench, lol. Stay safe, all. Dave.
 
Too light a load, smokeless takes fire and pressure to ignite properly.
Seen this happen a lot, especially with ball powder.
 
Hitzy said:
Too light a load, smokeless takes fire and pressure to ignite properly.
Seen this happen a lot, especially with ball powder.
Click to expand...

This is very true, but it may also be that the OP just encountered a bad primer.

OP, were your charges on minimum or less??? If so, Hitzy is likely correct but in my experience, there has to be quite an open air space in the cartridge for that to happen. Usually you get a hangfire or very light discharge. FTF does occur but not often.

Primers have a factory coating on them, to protect them from contamination. That doesn't mean your lube didn't cause that coating to break down. I believe it's mostly for small amounts of water moisture or oil/lubricant passed from fingers.

Primers are so good these days, that we seldom get misfires anymore. The days of expecting at least one bad primer out of a 1000 pack are over. That doesn't mean it no longer happens. Maybe you just got lucky???

You were trying to blow out the shoulder so that your cartridges head space on the shoulder, instead of the belt. Good idea IMHO.

Your headspace on the belt must be within spec, or you wouldn't have gotten the adequate firing pin strike you described.

IMHO, you had a one off, bad primer.
 
That's is what I am thinking. I tried a few rounds with no bullet or powder to test function and everything is working as it should. I noticed that not only was there a bit of powder clumping but there was a bunch tuck in the bottom of the case. My guess is lube contamination because I had put a fair bit in the case mouth when I was oversizing the neck.

For sure the Primer did not fully detonate. It was easy to see as this was virgin brass so the pocket was still shiny clean other than a very tiny black spot as compared to the other brass. To test my idea I primed and fired a new case and compared it to the FTF one and a big difference in the Primer pockets showing detonation.

Charges were not minimum they were max listed charge.
 
Last edited:
Eagleye said:
At our rifle range, we have a box to receive misfires. Just drop the misfires in there and they get
disposed of safely. I often clean out all the CF rifle misfires and take them home to disassemble.

Sort of an "Autopsy" I have seen several loads with the same situation as you describe. Primer
fired, but seemed to lack the brisance to actually ignite the powder, leaving some small "clumps".

I am of the opinion that there was some sort of contamination of either the primer or, possibly, the
powder. [moisture, oil, etc] In one case, it was very obvious that the powder was very damp, but
some were not so obvious.

Interesting observation. Of the "reloaded" misfires, fully 60% contained no powder!! I guess some
just do not pay enough attention while at the bench, lol. Stay safe, all. Dave.
Click to expand...

Makes you wonder if buddy had a couple shots that were twice as loud and recoiled twice as much...

I often pick misfires off the ground (haven't raided the bin to perform more extensive autopsy sessions) and what mostly appeared to be factory loads of CF and RF, light strikes seemed to be most common... or no strikes (dropped and not recovered). I've pulled some bullets to reveal a few unsightly messes... it isn't bad enough I'm a brass raccoon, now I'll be eyeing up the misfires boxes.
 
Hitzy said:
Too light a load, smokeless takes fire and pressure to ignite properly.
Seen this happen a lot, especially with ball powder.
Click to expand...

I have a few pet loads that are a light charge, including an 8gn 30-30 plinker that is just lost inside the cartridge. I also do a lot of my shooting in the winter, and I was told I would have regular ftf issues using a light rifle charge on freezing conditions, but I've always loaded with Magnum primers (on an old recommendation) and the only ftf I can rember are 2 seperate instances of what Dave described: turning my head for a second at the bench and a pixie stealing the powder back out of the cartridge before i seated the bullet.
Not ball powders though.
 
Case lube is highly unlikely to contaminate primers. Test have been done soaking them in oil, and contrary to internet myth, they are not always killed.
I have seen clumping before and it is due to low pressure loads that are partially scorched by the primer. Not due to lube contamination of the powder. I suspect a minimal powder charge, and exacerbated by fireforming resulting in really low pressure for the powder in use.
 
powdergun said:
So out today firing a few rounds.

I had 10 rounds with me and wouldn't you know it number 10 does not go off.

So here is my check list on finding out why and if anyone has any more to add all advice appreciated

1) Primer dent just like all the rest
2) brass was tight in the chamber as I was fireforming new brass with a false shoulder so not thinking head space
3) Dissasembled the round and it looks like the Primer went off a wee bit but otherwise prime pocket was clean but for a small black mark.
4) Poured out the charge and saw some clumps in the powder( oh oh sizing lube)
6) Tested the gun and the brass with an empty case and fresh Primer ( all went fine)

My conclusion was lube on the Primer or bad Primer ( Winchester magnum rifle primers)

If you can think of any other reason apply to here.
Click to expand...

Bad primer, plugged primer hole, lube contamination, or fairies.

You'll probably never know which and it doesn't matter. What does matter is you know it wasn't a mechanical misfunction with the rifle.
 
I broke a depriming pin the other day, didn't notice there was a 22LR case in the bottom of the .458 case I was trying to size.
 
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