Posted on 12/16/2016 9:29:08 AM PST by w1n1
I didn’t even know FR had a porn section.
Was disappointed when I got to the article and it was about shooting guns.
I was going to post something but my brain froze
I used the term ‘slide’ for those who might not be familiar with the actual name from the Marlin parts list. I knew that they would recognize slide from its function.
I had to cold forge my firing pin when I bought the rifle almost new from a friend because it was a little short and would occasionally not fire. It works fine if the slot it sits in and the firing pin are relatively clean. If the absorb too much lube, the firing pin does not hit the primer hard enough to set off the powder.
When the slot it rides in and the pin itself are relatively clean, it rattles back and forth freely when the breech-bolt is shaken. When too much lube moves into it, it will not. That is what I was trying to address.
By the way, I also own a model 39 from the year 1949 that belonged to my father. The problem is not evident in it. I do not think that rifle ever failed to fire.
“I used the term ‘slide’ for those who might not be familiar with the actual name from the Marlin parts list. ...”
Parts sellers and gun repair techs are endlessly bedeviled by terminology (I used to work for a parts & repair firm). Each gun manufacturer invents their own terms for parts and none see any need to coordinate what they are doing. Possibly the only nomenclature commonly used is “barrel.”
“I had to cold forge my firing pin when I bought the rifle almost new from a friend because it was a little short and would occasionally not fire. ...”
Your firing pin could not have been original.
Firing pins for the 39 (and its predecessor the 97 I think) have all been longer than the breechbolt; working the finger lever cams the pin off the cartridge head before the breechbolt is unlocked. When the breechbolt is pushed forward to chamber the next round, pin movement is blocked by this cam system until the breechbolt is locked in place.
If by “cold forged” maxwellsmart_agent means “stretch the firing pin by whacking with a hammer”, he could not have been working on a factory-made pin. Marlin heat-treats them until they might be the hardest part in the rifle. They shatter before stretching.
It works fine if the slot it sits in and the firing pin are relatively clean. ... rattles back and forth freely when the breech-bolt is shaken. ...”
Not an unknown malfunction. Parts that move freely by hand sometimes bind or stick when the gun actually functions: the velocity of the hammer and its impact angle on the firing pin are very different from any manually induced movement.
“... I also own a model 39 from the year 1949 that belonged to my father. The problem is not evident ...”
Sad to say, not an unknown trend.
Marlin once machined their firing pins from flat stock; pins of more recent make have been stamped. Ideally, burrs and irregular surfaces are removed after inspection and before final finishing. Bad ones aren’t always culled.
Could be out-of-tolerance machining or improper fitting of the breechbolt. Other parts might be involved too.
Does maxwellsmart_agent’s 39 have the late-model rebounding hammer?
I don’t think pulling them out of the lube and firing them is an accurate test. The problem with lube is that it adheres to dust. Pull them out of the lube and let them sit around for a couple of weeks, then check their dirt and grime level compared to control. Then fire them a few times and compare where that dirt goes and continuing operation.
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