1911 Slamfire Help

[TNMTBik3r]

My new Para 1911 Expert has around 400-500 rounds or so through it now, with no issue except a couple of feed failures.

Last weekend I shot it then stripped it down and cleaned it well. Today at a class I inserted a loaded mag, hit the slide release and the round fired. I cleared the weapon.

The instructor came over and performed the same steps. Load mag, insert, hit slide release - weapon fired. A gunsmith then inspected the weapon and cycled several rounds with no issue.

I am not home to research this, but is it a common issue? A weak firing pin spring? My plan is to clean the weapon and get back to the range (probably not until next weekend) and test to see if the issue repeats itself. I also plan to closely inspect the primers and see if there is any indent to indicate the pin striking on slide release. I did not think to check the ones we cycled today.

The ammo was PMC factory. If no issues at the next range session or indication of primer strikes I may say it was weak primers? If any issue I will send it back to Para.

[Joe357]

Is the hammer(following) hitting the firing pin when you used the slide stop to release the slide?

Is this just happening on the first round assuming you have more then one round in the mag? Edited June 1, 2014 by joe45

[Raoul]

How far did you "strip it down"?

[gregintenn]

Did you have any spare parts when you reassembled it? Like a firing pin spring?

[Westwindmike]

Sounds like the sear is not engaging the main leaf spring properly.

[Dolomite_supafly]

If the hammer is following there are a few things that can cause it. If it is not then replace the firing pin return spring. Also check to make sure the firing pin is rebounding. It is possible for it to slide under the firing pin stop and possibly cause this. A way to prevent it is to chamfer the hole on the back side. If that is if I will say if rarely happens on its own.

But if the hammer is falling it is something a little more serious and will require a little more work and cost to repair.

If you have been dropping the slide on an empty chamber you have ruined the sear. One of the worst things to do to a 1911 is drop the slide on an empty chamber. I have repaired quit a few guns, especially higher end ones, after friends decided it was cool to drop it over and over again. With sloppy fit 1911's it isn't as big of an issue although it can damage them as well but it does damage 1911's with lighter pulls and no creep triggers a lot quicker.

I had a friend who bought a very nice 1911, forget the brand, but it was far outside my price range and was a semi custom gun. He brought it down and we shot it and it was an amazing gun. Well 3 months later he called me because the hammer was falling when he chambered a round. He said 75% of the time it stopped at 1/2 cock but the other 25%it followed it home. I told him to not touch it until I looked at it because it can go offer if the hammer follows it home. I know this because I had a gun do that while I was setting the sear springs. Well when he brought it down the sear nose was rounded over. I asked if he was dropping the slide on an empty chamber and he said he figured it would help the break in if he did that. Well about 30 minutes later we had a new sear in place and it was once again acting like it should.

And the other big No-No with 1911's is dropping the slide on a loaded chamber. This will ruin an extractor pretty quickly as well. Sometimes you can tune it back up but more often it requires a new extractor and slide stop to fix the cycling issues.

Where are you located?

[TNMTBik3r]

I honestly am not sure if the hammer dropped on the two slamfires. The slide cycled so if the hammer fell it was recocked.

I have not dropped the slide on a loaded chamber but have dropped the slide a handful of times (seriously about 5 times or so) on an empty chamber.

No leftover parts and stripped down meaning field strip and firing pin removed to clean the firing pin chamber.

[TNMTBik3r]

Both of the slam fires were the top round in the magazine. But we then cycled a few other rounds through exactly the same way with no issue. The smith said everything looked and felt right during his inspection.

Oh and I am in Columbia Dolomite.

[TNMTBik3r]

Just stripped it down again. The firing pin spring IS longer than the firing pin. And the spring does not seem weak but I don't have anything to compare it with.

[TNMTBik3r]

Forgot to add earlier, the smith dropped the slide on an empty chamber multiple times testing to see if the hammer would fall. He probably hit the release 20 times. So our testing was about 25-30 slide releases with a mix of live rounds and no magazine/round and the hammer did not fall.
Since it was only the two rounds, hammer does not seem to be falling when the slide is released, could it be as simple as a high primer on the factory ammo? A high primer and slight pin protrusion when the slide is released would cause the slam fire - I shot the rest of that box in a different 1911 no issues, but will check other ammo at the next range trip and see if I am getting any dimpled primers when the slide is released.

[teecro]

One of the mods I've read about in effort to prevent a true slam fire (not hammer follow) is to purchase a titanium firing pin and an extra heavy firing pin spring... With the light weight firing pin and heavy spring it becomes all but imposable for the gun to fire if dropped etc.... Personally I don't think this is your issue and I'd lay odds that the sear spring is bent and/or not properly fitted to the sear. I've seen this myself while putting my own guns back together after a bench cleaning.

[Monkeyman2500]

I would definitely check the sear spring. I've never had any broken parts but it can happen.

[TNMTBik3r]

Yesterday we performed sear and safety function tests...is it possible that the tests could pass yet there still be an issue with the sear to cause the slam fire?

[Dolomite_supafly]

Yesterday we performed sear and safety function tests...is it possible that the tests could pass yet there still be an issue with the sear to cause the slam fire?

 Yep.

 

I would check is the sear spring like some have mentioned. And while you have it apart I would add a little more tension to the sear spring. On the 3 fingered spring it will be the middle leg that controls the sear pressure.

 

And if you feel comfortable I would check the nose of the sear. It should be square without any rounding or at least a minimal amount of rounding. New it was square but as the slide is dropped on an empty chamber it rounds the nose of the sear off and at some point it will no longer sit in the hammer notch.

 

Have you adjusted the trigger at all? It is possible to get the trigger adjusted to a point it becomes unsafe.

[TNMTBik3r]

No the trigger has not been modified at all. It does have the set screw to adjust over travel but I have not touched it.

I will try to detail strip the pistol tonight and check the sear spring. If I run into problems one of my neighbors has been shooting and smithing on his 1911s for 20+ years so I can grab him if he is home.

[div]

[quote name="Dolomite_supafly" post="1154399" timestamp="1401668754"] And the other big No-No with 1911's is dropping the slide on a loaded chamber. This will ruin an extractor pretty quickly as well. Sometimes you can tune it back up but more often it requires a new extractor and slide stop to fix the cycling issues.[/quote] I did not know this. I started doing this recently after noticing that I was getting some pretty severe bullet set-back on my self defense carry rounds (hornady critical defense) from the rounds being rechambered into the pistol after practice sessions.

[TNMTBik3r]

Based on my limited understanding and pics from Google, everything looks fine to me...

Edited June 4, 2014 by jonathon1289

[Dolomite_supafly]

Without removing at least the hammer there is no way to inspect the sear for damage.

Did I miss it, does the hammer follow the slide or not? That will tell me if the problem is in the frame or slide.

[TNMTBik3r]

No the hammer does not follow the slide.

The pics I found online showed just looking at the top of the arms pictured and if they are not rounded then everything is fine....I can continue disassembly tonight and remove the hammer.

[frankmako]

put in a new sear spring.  

[Dolomite_supafly]

It is not related to anything in the receiver. The sear is fine, the sear spring is fine and there is no need to disassemble.

 

Have you cleaned the firing pin channel lately? I will say that the firing pin spring should not be longer than the firing pin itself. Something is out of whack if it is unless Para is not building their guns to use standard parts.

[TNMTBik3r]

Yes I thoroughly cleaned the firing pin channel before and after the slam fires occurred. I did not notice any metal shavings.
The firing pin spring IS longer than the pin. I read that it is supposed to be longer. I can get a pic of it tonight as well.
I will remove the barrel and rack the slide multiple times to see if the pin is protruding at all when the slide is released.

[Joe357]

Just another item to look at. The para a series 80 with firing pin block(correct) and did you have your finger on the trigger?

[Dolomite_supafly]

A 1911 firing pin spring is not longer than the firing pin. It must be something Para does.

 

Do you mean the spring is longer than the nose of the firing pin when installed? Or is it longer when you lay the two next to each other?

[TNMTBik3r]

Finger was not on the trigger (laid alongside the frame above guard) on either of the slam fires - first happened to me and the 2nd was with to the instructor/RO.

Dolomite, I will double check the firing pin and spring when I get home.