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Old April 18th, 2021, 07:45 PM #41
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Quote:
Originally Posted by Melnic View Post
Here is the result
How does this come into play for a failure that occurs long before that link cams over to move the barrel up into the grooves to lock up?




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Because it's slowing down the timing sequence. The slide stop is "bumping" on that hump which causes a little bit of a stall, enough to slow down the timing needed to feed the next round.

There is a good possibility that there are other contributing factors as well. The feed ramp in the frame itself may not be deep enough which causes the round to stall a little coming out of the magazine, then the slide stop bumps, which causes another stall. It looks like the bevel on the link is chewed up a little bit, which could be a burr somewhere in the channel between the barrel legs and that can cause a little drag.

I saw you had checked extractor tension so I won't mention that. But, that is also a big contributor in failures to feed.

All of these things add up and eventually cause issues with feeding.
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Old April 18th, 2021, 08:22 PM #42
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This malfunction is a classic 3-point jam. Check out:
m1911.org, Click on Home Page link in middle of page, select “Technical Issues” from left side column on the page, click on 3-point jam.

As posted earlier barrel bump reduces the slide velocity because of the irregular feeding. It is said to stall the barrel on the pin thus stalling the cartridge being fed. The barrel bump needs to be corrected (mentioned in my earlier post). While you are working on the barrel, the barrel ramp to chamber wall at the bottom of the chamber opening should be gently radiused.

You may consider Wolff extra power mag springs. The 8 round capacity mags in the 7 round mag length bodies) sacrifice spring space for an extra round capacity. The top and second to top rounds many times will nose dive due to the lack of spring tension. The lost spring tension and the heavy column of metal the spring needs to support also prevents the round from maintaining proper ‘attitude’ during feeding. I used to just put 7 round followers and springs in the 8 round mags to just eliminate the malfunction. The new generation of 8 round mags are slightly longer allowing more spring in the mag. Push down on the follower of a Ruger full size or CMD mag. Lesson learned.

The longer narrower nose on the SWC you are using can be problematic, at least in my experience. I use the standard length/angle nose SWC since it is more forgiving - at least in my experience. Work on the length and and crimp after you get the pistol straightened out. As another member alluded to, it could be the reloads. If the slide is short stroking from underpowered ammo you can get misfeeds. Typically the rear of the case is pushed down in the mag. Weak mag springs can do that, too, since the round is not pushed up in time to be properly stripped from the mag.
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Old April 18th, 2021, 08:36 PM #43
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Quote:
Originally Posted by Bullfrog View Post
Probably causing the barrel to bump up just a tiny fraction of the distance before it's supposed to, so the edge is no longer flush with the feed ramp and has begun to rise before it should. That would probably cause the dents you're seeing, when the 'corner' where the throating ends bumps the case.

Also interesting to see the dot pattern on the bottom of the barrel. Digitally encoded serial or lot number?




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Old April 18th, 2021, 10:26 PM #44
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Quote:
Originally Posted by Pinecone View Post
Take a picture of the breech face. And the feed ramp area.
Quote:
Originally Posted by inkd View Post
Because it's slowing down the timing sequence. The slide stop is "bumping" on that hump which causes a little bit of a stall, enough to slow down the timing needed to feed the next round.

There is a good possibility that there are other contributing factors as well. The feed ramp in the frame itself may not be deep enough which causes the round to stall a little coming out of the magazine, then the slide stop bumps, which causes another stall. It looks like the bevel on the link is chewed up a little bit, which could be a burr somewhere in the channel between the barrel legs and that can cause a little drag.

I saw you had checked extractor tension so I won't mention that. But, that is also a big contributor in failures to feed.

All of these things add up and eventually cause issues with feeding.
what happens when I take too much metal off the corner?
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Old April 19th, 2021, 08:54 AM #45
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Quote:
Originally Posted by John from MD View Post
That bullet shape has been the standard for bullseye shooting with a 1911 before I learned about Bullseye shooting in the early sixties. The problem isn't the bullet.
Yeap. H&G 68.

I have shot 10s of thousands of them in various 1911s.
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Old April 19th, 2021, 08:55 AM #46
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Quote:
Originally Posted by wilcam47 View Post
Theres many stories on both sides, diferent brand guns, mags etc..just cuz it works in yours doesnt mean it will in his...
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Originally Posted by Trigger Tuner View Post
That's for sure and especially with the 1911. There are a lot of things happening at the same time or within a split second and often what works cycling by hand does not work when actually firing the gun. I have magazines that never cause a failure in one gun but I cannot not get threw one mag without jamming in a different another gun. That's why I suggested trying a different magazine first.
Yes, but that bullet shape has being shot in 1911s for decades. MILLIONS of them without issue.

Even the shorter and stubbier 185 grain SWC.
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Old April 19th, 2021, 08:56 AM #47
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One more pic for ya
I would polish that.
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Old April 19th, 2021, 08:59 AM #48
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Quote:
Originally Posted by Bullfrog View Post
I understand that, but I was probably unclear in the way I described what I had in mind.

I meant that it looked like they might be releasing the middle part of the case early while still grasping the rim, due to the inconsistent taper. That would make the round angle more, and earlier, possibly hitting the top of the chamber.

I've seen the parallel feed lips and the angled feed lips, but that last one doesn't look like either. They don't have a consistent angle to then at all.
The stepped version does release the front part of the round early, actually, does not touch it at all.

The bullet is pushed up by the feed ramp, and that controls the angle. initially.

Then the rim clears the step, and the spring/follower/next round, pushes the back end up, aligning it.

If the breech face is rough, it slows the movement of the rim end up to align the round. And you get the classic round angled up and jammed into the top of the chamber.
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Old April 19th, 2021, 09:01 AM #49
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Quote:
Originally Posted by John from MD View Post
Try some dummies with the shoulder level with the case.
Agreed.

The powder coated bullet looks a little longer than the lead one. And the lead one looks to be seated a bit long.

A long round will cause the round to tip up more initially in feeding.
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Old April 19th, 2021, 12:47 PM #50
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Quote:
Originally Posted by Pinecone View Post
I would polish that.
I will work on polishing the Breech face


Quote:
Originally Posted by Pinecone View Post
Agreed.

The powder coated bullet looks a little longer than the lead one. And the lead one looks to be seated a bit long.

A long round will cause the round to tip up more initially in feeding.
If you are referring to the post #25, the Green is a live round that jammed.
The dark one is as I mentioned in the post, a dummy I loaded with a longer OAL on purpose. (BTW, that is a bronze/brown Powder coat, not lead).

Green ones are all about .050" past case mouth.

Per Posts #37, I did make some dummies w/ the bullet shoulder at the case mouth.
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