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Discussion Starter · #1 ·
The short story is:

Through the long road of troubleshooting I found that with my factory Colt disconnector I had a variable trigger pull. 5 to 6 pounds after manual (thumb) cocking, 6 to 7 pounds after slide cocking.Little or no creep when manually cocked and lots of creep when actively cocked (cocked by the slide). I worked out all of the creep through basic troubleshooting, but still had a variable trigger pull regardless. Over all, the pounds pull decreased but the disparity between manually cocked and slide cocked did not, nor did the variability per stage.Though I did mange to get rid of creep. (Most of it was caused by a high spot in the frame just south of the center of the sear pin)

Frankly it boiled down to the disconnector, because that is all that was left. I ordered a Nowlin disconnector and installed it. Once the frame was re-assembled the trigger pull dropped to a scary 3 pounds so I reconfigured the sear spring and got a consistent 4, happy with that I re-assembled everything and got a very pleasant surprise. Regardless of attitude or whether or not the slide had been cycled I had a very nice 4 pounds pull.

Time for final. I sling-shot the slide. Good to go. I locked the slide back with the slide stop and let go. The hammer followed... Big frown, never had that happen before. Tried another sling-shot. The hammer followed. Inserted a mag of snapcaps with the slide locked back, the hammer followed. Double big frown. Guess I ain't shootin today. After goin back over everything I did, over and over, same result, I dropped the original Colt disconnector back in and dropped the slide. NO hammer follow. I have swapped three times and the problem follows the disconnecor. I have mic'ed them both and just can not see any dimensional differences.

I am confounded and not convinced it is the Nowlin disconnector. Heck, the creep had nothing to do with the sear nor the hooks as one (newbie) might expect.


Thanks for your insight.
Ruff.

The long story is yours for the askin.
 

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There has to be a difference if that's the only part causing it.The original Colt one is probably rough on the bottom of the hole where the sear pin rides so POLISH it (not remove metal) but watch the top for a bind in the frame hole if it's toleranced tight and rides the slide cut,there's a cure if you need it.Not sure about the Nowlin causing follow if it mikes the same as you say.Unless you're getting a trigger slap on a 4lb trigger (?) it's gotta be a spring thing,did you touch the DIS leaf or just add on to the sear leaf.

Did the center leaf slip under the DIS?
 

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Ruff - Just thinking this through. First, the difference in what you feel occurs only when you swap the disco, so it has to be disco-related. Second, you can find no dimensional differences in the two discos, so it has to be a difference in how each disco is acting while in the gun (interacting with other parts). Suggest you check to make sure that the new disco isn't binding on the pin, and if it is, relieve the disco hole. Also, consider trying a Bul or STI big-head disco, which should fix the problem if it's how the disco heads are acting in the frame.

Best,
Jon
 

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consider trying a Bul or STI big-head disco, which should fix the problem if it's how the disco heads are acting in the frame.

Best,
Jon
BINGO


my Kimber factory disco comes with a big-head....a Wilson disco(non-bighead) would induced hammer follow.... full auto mode upon ignition.
 

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...I found that with my factory Colt disconnector I had a variable trigger pull. 5 to 6 pounds after manual (thumb) cocking, 6 to 7 pounds after slide cocking... I worked out all of the creep through basic troubleshooting, but still had a variable trigger pull regardless. Over all, the pounds pull decreased but the disparity between manually cocked and slide cocked did not, nor did the variability per stage... (Most of it was caused by a high spot in the frame just south of the center of the sear pin)

Frankly it boiled down to the disconnector, because that is all that was left. I ordered a Nowlin disconnector and installed it...

Time for final. I sling-shot the slide. Good to go. I locked the slide back with the slide stop and let go. The hammer followed... I dropped the original Colt disconnector back in and dropped the slide. NO hammer follow. I have swapped three times and the problem follows the disconnector. I have mic'ed them both and just can not see any dimensional differences...
Ruff, go back and re-measure both discos carefully. Distances from (1) bottom of the hole to the very top of the disco, (2) bottom of the hole to the top of the paddle, (3) diameter of the disco head, & (4) thickness of the paddle in particular. Reassemble the frame minus the grips, thumb safety, & grip safety. Do the following tests with slide on & slide off. Just don't drop the hammer hard on the frame bridge. Use some good light & magnification to observe the interaction of the paddle with the sear feet. If (1) is different between the two discos, the disco relief in the slide may be barely pushing down on the tip of the disco and need to be deepened with a scraper. Check how smoothly the head of the disco moves through its hole on the frame. If it's tight & there are some burrs, it can possibly cause a little hesitation depending on spring tension & result in the disco coming to rest in a slightly different position when it is moved by the slide during cycling. Lots more to examine, but this is a start.
 

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Discussion Starter · #6 ·
Disconnector

Thanks fells!

Rex, I'm going to focus on the frame hole and pin, the disco its self is smooth, no burs. I set the sear/disco spring using a trigger pull scale (per Jack Weigand). I always set/check both the sear spring and the disco spring any time I make a change. I'm not thinking its a spring thing because the same spring works with the factory disco.

BigJon & BBBBill, I am going to re-examine them side by side very carefully. Will put the mic to them again following your map. Then will do the tests as you describe.

Just to make sure I am understanding you fellas. I am looking for pin binding where the sear pin passes through the disco. Looking for a smooth transition of the disco head through the frame hole. Checking the disco relief in the slide. Comparing the interaction of the old and new disco paddle with the sear feet.

Thanks again. You gents are great! I just might end up with two good discos. The factory one only has 3000ish rounds on it.

Will report back soon,

Ruff
 

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Discussion Starter · #7 · (Edited)
Disco measurements

Ruff, go back and re-measure both discos carefully. Distances from

(1) bottom of the hole to the very top of the disco: Old= .832 New= .829

(2) bottom of the hole to the top of the paddle: Old= .306 New= .300

(3) diameter of the disco head: Old= .155 (on the fat side) .151 New= .152 all around. Funny the Colt one is oval. Might the head on the new disco be a little small as Zdragon and BigJon suggested?

(4) thickness of the paddle in particular: Old= .034 New= .047

Overall height: Old= 1.295 New= 1.291

My observations all questionable. LOL!
The new disco is shorter in all respects so the disco relief should not be a factor.

The fatter paddle should have increased tension on the disco leaf of the sear spring not reduced it. (Scratchin head)

The oval head on the Colt disco is causing me pause. Note to self, look very close at the disco hole in the frame.

This is fun! Ok so it did not match up quite as close as I thought after guided measurements.

Ok I am off to run the rest of the tests on both discos.
 

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Discussion Starter · #8 ·
New development

A fella thought maybe the disco was a tad short so he asked me to do a reset check. Hand cycle the slide with trigger pulled, release slowly until reset. So I re-assembled. And sure enough it reset, bummer. But figured that since it was back together I should run the safety checks. Popped in a mag of snap caps, gently cycled the slide. No problem. Performed a sling shot to simulate firing. No hammer follow. Dropped from stop on a cap... No hf. Popped out the mag did a (cringe, I hate this check but have learned it is essential) slide drop from stop. NO follow! GAAAHHH!!!

The biggest difference is... I omitted the two firing-pin safety levers (series 80) in the frame to expedite reassembly to check for reset. Somehow the geometry of the firing group is being skewed by the fps levers. Another difference is I grabbed the old sear pin instead of the new one that was installed with the new pin set... The plot thickens. I need to try it with all the parts in and using the old pin. If everything works then it is definitely a sear pin/disco relationship problem. (The old factory pin was pretty sloppy would drop out without being drifted) The wear on the old disco and old pin probably allowed somewhat normal function. I better stop jumping to conclusions and start testing.

Just more pieces to the puzzle.

Ruff
 

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Discussion Starter · #9 ·
ruled out

Back at it. Ruled out the worn sear-pin/new sear-pin hypothesis. Installed the old sear-pin with the firing pin safety bits. Hammer followed with a routine slide cycle.

It seems to me that everything is beginning to focus on the sear and disconnector relationship, as having the firing pin safety parts in place tightens the channel, giving less play to the sear, thus forcing the disco to the left inside the channel for it provided within the sear.... OMFG!!! just writing this has made me visualize the parts interaction and I picked up the old disco and under magnification its right side (looking from the rear of the whole) has a very distinct grove worn into it along the axis of the sear pin. Without magnification it only looks like a scratch. Under magnification it looks like a channel!

Not going to jump to a conclusion but need to address the disco channel inside the sear. BRB
 

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Discussion Starter · #10 ·
Thank you! Thank you! Thank you!

You Guys Rock!

Your questions and tips led me to the answer. I now have two good discos.

It was an invisible burr in the disco channel of the sear. After having the epiphany about the firing pin safety bits narrowing the channel for everything thus skewing the sear, thus skewing the disco, the only place left to look was in the disco channel of the sear.

Even with bright lights and a decent loupe I cold not see anything wrong, so I followed the gut and dragged a fine file lightly across the right side of the inside of the sear. It might as well been stuck in mud. Drug the same file across the left side, smooooth. AHA!!!

Filed her out, polished her up, badabing! I did a double back flip.

This (the 1911) has got to be the simplest most complicated piece of art I ever had the pleasure of working on.

I can not thank you enough for bearing with me, giving sound advice and not shootin me down. :biglaugh::rock:
 

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Way to go, ruff!!!!! You asked, you listened to the answers, you implemented the advice, you used your noggin in the process, you learned something new, and then you came back and reported and even said "thanks."

With that initial track record, my prediction is that you will enjoy a long and pleasurable experience here and be given tons of information, both in public posts and by private message.

Congratulations on your successes, in fixing your pistol and in presenting the best-possible approach on the forum. More will undoubtedly follow in the future - on both counts.

Best,
Jon
 

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Disconnector

The disconnector hole of the frame can sometimes cause problems. If the hole is too large for the head of the disconnector, it can allow the disco to start to move when the trigger is pressed. It can feel like creep, and if the disco moves after the slide is released from slide lock, it could possibly move the sear just enough to disengage from the hammer hooks. I don't recommend slamming the slide shut without a round in a mag, since it causes the firing control parts extra stress and can cause trigger bounce.

When I have an overly large disconnector frame hole, I remove the slide, and observe where the most disconnector movement is seen when I press the trigger. If the disco moves slightly forward, then I take a center punch and stake the hole on the front edge of the disconnector hole of the frame. Usually one good tap with a hammer and punch will close the hole slightly. If the disco hole is excessively wide, I stake the hole on the side. If the frame hole closes too much, it is a simple matter to take a round needle file and enlarge the hole so you get a good fit of the disconnector head through the frame hole.

If there is excessive movement of the disconnector due to a large disconnector hole in the frame, when the trigger is pressed, often times the disconnector may move forward. If the top of the disconnector head is touching the slide within the recess notch, then this can cause a feeling of trigger creep also. When I do a trigger job and get my trigger perfect and no creep, I then check it with the slide on. If I feel trigger creep only with the slide on the frame, then I know the disconnector is rubbing on the slide. Once again, I will peen the disco hole to reduce disco movement, and often times I will deepen the slide disco recess notch.
 

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Through the long road of troubleshooting I found that with my factory Colt disconnector I had a variable trigger pull. 5 to 6 pounds after manual (thumb) cocking, 6 to 7 pounds after slide cocking.
This is what initially pointed me to the Infinity disconnector long ago, before I learned of the Bul big-head unit or the new one from EGW. Check the third paragraph:

http://forums.1911forum.com/showpost.php?p=21796&postcount=1
 

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Discussion Starter · #16 ·
Lights are going off all over the place

BigJon,

You did nail it right off. The disco was binding, but in this case it was inside the sear. As a matter of refinement I am checking into the three big-head discos you mentioned. Will probably upgrade to one of them (most likely the EGW just cause I like their stuff). The third paragraph of Metal Smiths post is one of those pearls I need to tuck away and add to my standard checks.

Refining this 1911 is becoming a passion or maybe an illness, not sure which.

Lots more questions to come. This Colt is nearing what I want it to be. The next project is laying on the bench. A surprisingly well made STI frame, not that it comes from STI but that externally the Colt frame matches its quality, inside the frame the STI is exceptional, it makes the Colt look like a hammered out iron parts box. The difference causes me pause.

Any one have a slide for sale? :D
 
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