1911 Lesson

[Glen]

I learned something recently and thought I’d pass it along. A friend brought me his Colt Defender (small frame 1911) that he’s had for 2-3 years. The hammer was stuck at full-cock and the trigger was rigidly locked up. The slide and safety still moved freely (yes, the chamber and magazine were both empty). With the slide removed, after a fair amount of fiddling we eventually got the lower half to function properly (i.e. we could drop the hammer), but that ability was lost as soon as we re-installed the slide. Long story short – there was a small amount of a black, tarry, sticky residue that was hindering motion of the disconnect in its “rabbit hole”, and that had essentially glued the spring/plunger of the firing pin safety in place. A good thorough cleaning got rid of the tarry residue, and lubing the gun with Break-Free had it functioning like new again.

When I delivered the gun this evening, he asked me what the problem had been and I described what I had seen, and suggested that perhaps he’d had a pierced primer. A light came on in his head, “I bet I know what it was!” It seems he had been out plinking with a friend. As things were winding down, he had a “misfire” on his last round. He re-cocked the hammer and tried a second time, still no luck. Figuring it was a dud primer, he cleared the round into his range bag so he could down-load it later. Later, when he was sorting his brass, he came across that round and was surprised to find the primer had been seated backwards, and was charred. Apparently when that primer fired enough residue blew back between the slide and frame to gum up the disconnect and firing pin safety (there is probably also some in the firing pin channel too, that I didn’t see). Yes, he should have caught this backwards primer before it got to this point, but I thought that I would share this experience just in case anybody has a similar incident in the future, in an effort to make their diagnosis and repair easier.

 

[Rushcreek]

I’ve wondered what would happen in that instance before, thanks!
He needs to inspect each cartridge in the box from now on……

 

[Glen]

Addendum: The more I think about this, the more I suspect that primer flame shot down the firing pin channel, then down the spring plunger of the firing pin safety, forcing the nearby disconnect down and depositing all that "soot" inside the disconnect channel.

 

[smokeywolf]

Thank you Glen. Always look to your postings with great interest. This is another that doesn't disappoint.

 

[Petrol & Powder]

While there is evidence of a primer seated backwards, I’m not convinced that one primer was the sole source of the trouble. Sounds to me like there was serious neglect of maintenance in addition to that one little backwards primer.

The evidence is right there in the owner’s statement, “…. he had a “misfire” on his last round. He re-cocked the hammer and tried a second time, still no luck.”. He was able to re-cock the hammer and drop it again, so the action didn’t lock up immediately after the primer fiasco. That sounds like the gun had not been cleaned in ages, or poorly cleaned. The backwards primer may have simply been a coincidence and not the cause. After the gun was idle for a while the action got stuck.

The presence of “….black, tarry, sticky residue…..” sounds more like dried up or gummed up oil mixed with burnt powder, dirt, whatever. The debris from a single primer alone probably wouldn’t push you over the edge into the territory of a locked-up disconnector and/or firing pin safety.

 

[Missionary]

I would wonder how many rounds had been fired also. Plus what ammo under what conditions.
Hard to beat regular maintenance when it comes to reliability in any machine.

 

[Petrol & Powder]

I’ve seen some pistols tolerate an astonishing amount of neglect and still function. But every mechanical device has its limit. I could fill pages with accounts of poor maintenance and the resulting failures but so could everyone else on this forum. I think most people have seen the results of failure to clean guns.

When the firing pin is protruding through the hole in the breach face, there’s not a lot of clearance between the firing pin and the inside perimeter of that hole. Furthermore, that space inside the firing pin tunnel is filled with the firing pin, maybe a spring, and the pin usually has some protrusions on it. It’s not a straight, unobstructed pathway for debris. There’s not a lot of room for the debris from a single backwards seated primer to travel down.

I think what we have here is a correlation. The pistol stopped working about the same time a cartridge with a backwards primer was present. Correlation does not equal causation.

Example of a correlation and false conclusion: There’s a direct correlation between fire truck sightings and fires, therefore – Fire Trucks must cause Fires.

It’s entirely possible (and I would submit probable) that the gun in question would have ceased to function even if that backwards seated primer had not been present in that last round cycled.

 

[RBHarter]

It may be a case of the camel straw .

I had a P35 clone that suffered battery failure continuing and worsening . Cleaning, OAL etc helped . Turns out there's a channel that as near as I can figure is a clearance cut intended to keep the trash out of the action parts . When you dig out a chunk of lead , copper , carbon, desert dust , and burned lube about the size of a pellet of elongated #4 shot feed and function returns .

 

[Glen]

Overall, the gun was pretty clean. He told me that it had about 100 rounds through it since he had last cleaned it (a mix of commercial hardcast and jacketed), and from what I saw inside the gun I believe him. I suspect that the tarry gummy stuff I found was due to whatever he was using to lube the gun (unspecified) getting fried by the primer flame, and the residues left from the primer. The overall cleanness of the gun is also what leads me to believe the primer flash went down the firing pin channel, instead of between the frame and slide.

 

[bruce381]

backward primer did the anvil get stuck somewhere if it fires the anvil would blow off.

 

[Petrol & Powder]

Overall, the gun was pretty clean. He told me that it had about 100 rounds through it since he had last cleaned it (a mix of commercial hardcast and jacketed), and from what I saw inside the gun I believe him. I suspect that the tarry gummy stuff I found was due to whatever he was using to lube the gun (unspecified) getting fried by the primer flame, and the residues left from the primer. The overall cleanness of the gun is also what leads me to believe the primer flash went down the firing pin channel, instead of between the frame and slide.

"He told me that it had about 100 rounds through it since he had last cleaned it (a mix of commercial hardcast and jacketed), "

And how much did he clean it before he gave it to you to fix?

Only had 1 box of ammo shot through it......
Owned by a little old lady and only driven to church on Sundays.......

 

[fiver]

but that single primer could have cooked and pushed the gunk into the wrong places.
there's enough force there to push a 200gr. bullet at least an inch into rifling, it isn't unthinkable for it to shove some lint, oil and other gunk into the wrong place.
especially some of that hard waxy commercial lube.

 

[Petrol & Powder]

Yeah.........sure......

 

[CZ93X62]

Machines can get into all manner of trouble for all sorts of reasons. I can't think that a primer firing in the exact opposite direction it was designed to function in did the slide much good. Primers are POWERFUL things. I think what has gotten lost here is that Glen correctly diagnosed the issue and corrected it, then shared that outcome here.

 

[Petrol & Powder]

I have no doubt that he correctly diagnosed the problem (The struck disconnector due to that black, tar like crud locking up the sear/hammer/disconnector). And clearly, he fixed it.

I’m a bit skeptical that a single backwards primer “cooked” the oil, bulletlube, powder residue or whatever was in the gun to the point that it locked the action up.

There’s a lot of mass between the breach face and that disconnector. And the exposure to that tiny bit of burning material from the primer is extremely short in duration. I’m also having difficultly envisioning how that flame (ever so brief) made it around the tip of the firing pin, down the firing pin tunnel around the firing pin and spring, and then made a 90 degree turn and got beyond the tip of the disconnector (which would have been in the raised position at the moment of firing) and somehow cooked the oil down inside that hole in the frame where the disconnector lives.

And the owner said he was able to re-cock the hammer after that backwards seated primer went off. So, the action didn’t lock up immediately after that malfunction. The problem manifested after the gun sat for a while.

I think the grease/bullet lube/ oil, whatever, gummed up and the action then started misbehaving. The backwards primer just happen to occur at the end of the shooting session and got associated with the subsequent mechanical problem.

 

[fiver]

K then.
i guess we wet tumble so only the outside of the cases come clean.
there's never any hard black residue in any of MY cases.