1911 jam

[chris in va]

Looks like it could be one of my loads. I tried some middle power (ie factory recipe) 225's and 200's and they all ejected the last case fine, although over the top of my head.

The one that kept crunching cases was my 160gr bullets. I love shooting these but apparently I'll need to use a different recoil spring as the timing must be way off, probably not enough mass to cycle properly.

Thanks for all the suggestions!

 

[1911Tuner]

Here's what's happening:

The case is falling off the breechface because the extractor isn't holding it.

Because there isn't a round under it to support it and help kick it out of the port, it gets dragged partway back into the magazine, depressing the follower and preventing the slide from locking back.

The slide keeps moving and rips the case rim from the extractor claw.

The slide runs forward and tries to feed the trapped empty case...now sitting in the magazine at an odd angle...and crushes it between the breechface and the barrel hood.

There are two possibilities:

Either the extractor is rotating counter-clockwise far enough to drop the case...usually caused by the extractor channel being located too far to the right or the lower edge of the extractor tensioning wall has been heavily beveled, and when the barrel drops, pulling the case down with it, the case rim loses contact with the part of the wall that keeps tension on it...and falls off the breechface.

If it's the first one, the only cure is a new slide with a correctly located extractor channel.

If it's the 2nd one, a new extractor...prepped by someone who understands that there's a limit to how much bevel can be used on the tensioning wall.

 

[mehavey]

Looks like it could be one of my loads. I tried some middle power (ie factory
recipe) 225's and 200's and they all ejected the last case fine, although over
the top of my head.

The one that kept crunching cases was my 160gr bullets. ...but apparently
I'll need to use a different recoil spring

We have met the enemy......


Wolff to the rescue for apparent short-stroking with (very) light loading.

 

[JohnKSa]

... it gets dragged partway back into the magazine, depressing the follower and preventing the slide from locking back.

How weak are the springs in a 1911 mag? I've never seen a mag with springs so weak that a loaded cartridge, let alone an empty, could depress the follower at all.

 

[HiBC]

Its a recoil operated pistol designed around a 230/240 grain load. Its no surprise lightly loaded 160 gr bullets would present a different recoil impulse.

Note if the slide is not traveling back far enough to reliably be caught by the slide stop,its not traveling far enough back for the ejector to do its job.

I had a Commander size pistol that was intermittent with holding the slide open on the last round. I put in a 2 lb lighter recoil spring. Problem solved.

Simple,cheap fix for problems caused by light loads. Easily reversible.

You still might need extractor tuning.

It might be a good time to mention : DO NOT drop single round in the chamber of a 1911 pattern pistol and drop the slide on it. Thats one was to screw up your extractor. The extractor is not designed to flex to snap over the rim. Its designed for the cartridge to be fed up the breech face from the magazine,sliding under the extractor. Thats important.

If you have an available good pistolsmith, just let the smith tune your extractor.

While there is a commonly used method of bending the extractor using the hole in the slide, IMO,its much better to just buy (or make) the extractor adjusting tool.

https://www.brownells.com/gunsmith-...ensioning-tool-prod16110.aspx?avs|Make_3=1911

 

[1911Tuner]

How weak are the springs in a 1911 mag? I've never seen a mag with springs so weak that a loaded cartridge, let alone an empty, could depress the follower at all.

If the case gets pulled back under the feed lips, it doesn't rely on weight to depress the follower.

The photo the OP provided shows what happened. Look at it again.

 

[1911Tuner]

Here's a little better picture.

https://carolinafirearmsforum.com/index.php?threads/tuners-troubleshoot-time.112726/#post-1894281

 

[44 AMP]

I think 1911 Tuner gave a pretty good explanation of what is most likely going on.

Let's look at what we know, and remember that during the entire process, things don't have to go completely wrong to cause the problem, just wrong enough, at the wrong time.

Last round fired case fed back into the chamber.

this means there are two things not happening. Fired case is not being ejected, and the slide is not locking open. And they are happening at what looks like the same time.

But, is it? exactly??

First, the extractor IS pulling the fired case out of the chamber. (and the rear of the barrel is pointed down when it does this -unlocked-)
And, this happens before the slide has moved back far enough to allow the slide stop to engage.

And here's where timing comes in. Where, in the process in YOUR gun is the slide at the point where it normally ejects? Is the slide in position to have the slide stop hold it open at THAT point??

I ask because I'm too lazy to go get my Govt model and play with it, right now AND, because your gun might be slightly different from mine...

IF, as suggested the extractor is hanging on long enough to pull the fired case back and slightly down (and slightly depressing the follower) just enough, and at just the right time to keep the slide stop from engaging, and THEN letting go so the rearward movement of the slide does not kick the case out when it hits the ejector this could explain how your problem is happening.

Time to play with the gun... remove the recoil spring, so you can slowly move the parts by hand, and using a fired case, work the cycle slowly, watching to see where the slide is, in relation to the stop and when the case hits the ejector, and how much more the slide moves back after that.

Also consider this, might the magazine (follower) be playing a part?? Does the last round jam happen with every magazine?? Just some?

Do you have a GI spec magazine? Can you test with one? does it happen with one, or only with "other" magazines??

I know the GI spec guns pretty well. I know what their parts should do, and when. BUT, when dealing with a non-GI spec gun/parts the "rules" can become guidelines and tolerances can vary.

Just for example, look at magazines. Today you can have several different designs of followers, and a couple different styles of feed lips, 8rnds vs 7 etc. Point here is, things have been changed from GI spec. When that happens, the "standard" things may apply differently and you have to work with the gun in your hands to find out what, where, and how much the differences are, in order to make allowances for that.

 

[1911Tuner]

this means there are two things not happening. Fired case is not being ejected, and the slide is not locking open. And they are happening at what looks like the same time.

Go back and look at the OP's photo and the one I just linked to. The case rim is UNDER the feed lips. The follower can't rise and engage the slidestop. Before the slide ran forward again, the case may have been completely in the magazine before the extractor was ripped off of it.

 

[mehavey]

My interpretation is different.
- The extractor pulled the case, holding the right side of the case
- The slide short-stroked, but the front of the case came free of the chamber
- The ejector never came into full play to kick the shell fully right & out.
- The slide began to re-close with the case cocked ever slightly up
- Extractor held the right side of the rim, left side was loose
- Moving forward, right rim began to ride under mag lip, left on top.
- Everything continued oriented that way, until hitting the top chamber shroud
- Boom.

Observation:
Gun functions totally normally until extremely light (160gr) bullet used.


1st Move (IMHO): Wolff Pack

 

[Jim Watson]

Could be. Mr Browning thought a 200 grain bullet was right, I tend to agree.

 

[1911Tuner]

My interpretation is different.

That doesn't explain why the case is part way in the magazine.

This ain't my first rodeo. I've seen this exact problem more than a few times. In all but one, the extractor channel was located too far to the right and angled, causing the extrctor to clock. In the one exception, the extractor had been "tuned" by someone who didn't understand that when the barrel drops, the case drops along with it.

Anyway...I was asked to take a look at this thread. I did. Cheers.

 

[JohnKSa]

If the case gets pulled back under the feed lips, it doesn't rely on weight to depress the follower.

There is no possible way for the case to get pulled back under the feedlips while the extractor has it. The case is extracted well above the magazine feedlips as can be easily verified with some experimentation.

Before the slide ran forward again, the case may have been completely in the magazine.

Get your pistol out and try to replicate what you are describing with an empty case. You will very quickly see that the case comes out of the barrel much too high to end up back in the magazine.

Also, If the extractor on his particular gun really were pulling the case out of the chamber and re-inserting it into the magazine the gun wouldn't work with any loading--the last round would always hang up. The OP has already stated that with other than light loadings things work fine.

So, what about a hotter loading causes the extractor to start working right and stop it from loading empties back into the magazine? If what you are saying is true, then the hotter load would cause the slide to lock back, but the empty would be just left inserted into the magazine once it stripped off the extractor.

Clearly what happened was that with the hotter loading, the ejection started working (and the slide started locking back) and once the case was ejecting it wasn't hanging around in the chamber area where the slide could close on it.

The case rim is UNDER the feed lips.

It is quite obviously not "UNDER" the feedlips. It is jammed down into the feedlips from the top with part of the case head being between the feedlips but most of the case head being above both feedlips.

The case was extracted, but the loading didn't create enough force to lock the slide back or to get the case ejected properly . That left the case loose of the extractor but still in the chamber area. It bounced back down and when the slide tried to close, the front of the empty hit the slide and the bottom got jammed downward into the mag from the top under the considerable force of the slide closing. You can see how much force was applied by how it bent the case mouth.

In all but one, the extractor channel was located too far to the right and angled, causing the extrctor to clock.

Fortunately, using a hotter loading moved his extractor channel back to the proper location and angle.

 

[chris in va]

As an update, I used mid-level charges with my 200gr SWC and 225gr LRN in an 8rd ACT mag and had zero issues. I'll just stick with that from now on.

 

[HiBC]

I can't say I know for sure,but looking with an open mind, and really giving 1911 Tuner's idea a chance, I can give his sequence a "Seems Possible". I looked at the photo, and I imagined the sequence as he described with the idea "Can I see it work?"

Two clues: The gash in the case above the mag lip was likely cut by the mag lip.

It looks to me like it would have to have been cut while the case head was moving down and to the rear. Then it was hit by quite a bit of force....As the slide was traveling to the rear. Look at the crush on the case mouth. It looks to me it occurred while the slide was traveling rearward under recoil,as the case head was stopped on the magazine. It would be interesting to check if the mag lips were spread.

I just don't think the case mouth would look quite like that if the slide was traveling forward and driving the case.

I'm not declaring a verdict. I'm saying I can see 1911 Tuners diagnosis has merit.

Its been a while since I watched high speed camera slow-mo of the cycling of a semi-auto,but it can be far more dynamic than we imagine.
Extractor tension needs to hold the case head on the breech face. Enough to not easily "Shake Off" 1911 Tuner brought up the motion of link down in a way I had not really thought of before. I'm having a hard time visualizing the exact timing,but the barrel with cartridge brass is accelerated downward and rearward till the barrel suddenly stops on the frame.
That should be when slide and barrel are fully unlocked and extraction begins. As the case is being drawn out of the chamber, the gun is going to buck up and to the rear. The timing just might be right for the case head to meet the mag lips as the slide chops the case mouth.

Could happen.

A 1911 will run when its not "quite right" IF you find the right ammo with the right recoil impulse you find a "window of operation" that works.

Its running with your 200 grain loads. Great!! But I suspect your extractor still needs tuning.

It should not have let the 160 gr load fall off the breech.

 

[chris in va]

I may have figured out why my last round jams on occasion. I took out the extractor and it rotates a little, so I have the dreaded 'clocking' problem. The case is slipping off the extractor and returns forward, crunching it.

The interwebs mention a slightly larger firing pin retainer plate, any experience?

 

[44 AMP]

Before you get another part (or three), try a fix.

Shim it.
So that the firing pin stop and the notch in the extractor are a snug fit with no play or twisting.

Then shoot and see what happens. Shoot the same thing that jams, and see if it makes a difference. If it does, there you go, you know what to do to fix it permanently. If not, your problem lies elsewhere and the troubleshooting needs to continue.

 

[JohnKSa]

Yup, upon further reflection, my analysis above is incorrect.

 

[chris in va]

I'll have to try that! The part comes in a couple days but will try that first as it "requires fitting".

 

[HisSoldier]

"The interwebs mention a slightly larger firing pin retainer plate, any experience?"

In the few 1911's I've fitted up I always buy the oversized FPS and machine it to be a tight fit (not cussing tight), making sure the groove in the extractor is flush with the groove for the FPS. In short, my extractors cannot clock that way, there's no way they can turn.
There's a website that shows the most effective extractor hook configuration, a little work with a small arkansaw stone smooths the passageway the cartridge travels up under the hook. (https://www.m1911.org/technic2.htm)