[Lionfan58]

After shooting hundreds of rounds my 39AS suddenly has a FTF issue. In the middle of a shooting session my 39AS has decided not to fire. Disassembled, and I found nothing broken. Reassembled and it fired one shot before the problem surfaced again, leading me to believe the problem is fixable. Any Ideas?

 

[Marvlin]

What do the firing pin strikes on the cartridges look like?

 

[Lionfan58]

Marvlin There is a slight dent in the rim of fired rounds. No sign of dent in FTF rounds.

 

[navajo]

When you say dis-assembled, I assume you removed the firing pin and
inspected it, right?
Just checking...
Also, could it possibly be the CBS?
Most of my FTF issues had to do with those,
until I disabled them.

 

[Lionfan58]

Navajo. Firing pin was removed and seemed OK. Noobie question here, What does CBS stand for?

 

[Pig Ninja]

" Cross Bolt Safety"

 

[Lionfan58]

Pig Ninja Thanks for the info.

 

[MarlinManCB45/70]

" Cross Bolt Safety"

The CBS is a "lawsuit protectionary" addition on "later" Marlin LA rifles. it is a redundant type set up.

The "early "ones didn't have it. It can be removed and replaced. Several different options on how to do it/style wanted"

Saddle ring conversion is one of them.

FWIW ..the CBS often results in a "missed shot opportunity" due to one forgetting to place the CBS safety in the "off/fire" postion, especially for those more accustomed to the earlier Marlin LAs,

 

[packard]

If your rifle has a CBS it also has a rebounding hammer, another lawyer mandated feature. It uses part of the hammer spring energy to rebound the hammer. If someone has installed a reduced power hammer spring, or the spring is weak, Light firing pin strikes will happen.

There is a sticky on how to remove all or part of the rebound feature. Result---no more light firing pin strikes.

 

[VinceA]

Is the bolt going all the way into battery? If it isn't closing all the way that can cause light strikes too and FTF.
V

 

[Lionfan58]

Update: I broke down the rifle one more time and double checked everything again. Took it out back and damned if it didn't shoot over a hundred rounds with two FTF in a row about half way (it happened right after a reload). It wasn't the rounds because they both fired when reloaded. Now I'm really scratching my head. I don't believe in ghosts' so that's out. Hopefully it won't happen again.

 

[scorpio]

Update: I broke down the rifle one more time and double checked everything again. Took it out back and damned if it didn't shoot over a hundred rounds with two FTF in a row ...................

..................Hopefully it won't happen again.

I've watched several cartoons where elves fix stuff while people are asleep.....

I don't see this problem fixing itself. It will happen again and slowly drive you mad until you figure out what the problem is. Intermittent failures are the most maddening ones too. You get to thinking things are cool and than the rifle fails when you need it most.

I'd start with a complete take down (as far as you are comfortable with) followed by parts inspection and good cleaning, even if you already cleaned it, and then start replacing springs. I'd also look for unusual wear on surfaces.

 

[Boobarzo]

Had the exact problem in one of my JM 39A.Replaced hammer spring for instant fix.They are only $4.I keep one on hand.