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Discussion Starter · #1 · (Edited)
I'm building my first 1911 with the parts from a 1943 Colt and a brand new RIA frame from Sarco. I'm familiar with 1911's, I trained with, field stripped & cleaned a lot of them while in the USN, just never built one before. I also own three other 1911's, an Auto Ordnance, a Para Ordnance P10-45, and an ATI 1911-22 (which doesn't really count).

This particular set of parts was purchased by a friend of mine at the last Seattle gun buy back. The previous owner had put them into a 1911 .22 frame and managed to fire a single round jamming the slide back & ruining the frame (big surprise). As far as I can tell, there is no damage to the Colt parts, and my friend (who is a smith) has helped me when I've run into problems with the build including diagnosing this problem, but he had to leave before we came to a solution.

Here's the problem:

When the slide runs over the disconnector (or you push it down with a punch), it "clicks" down & stays down even when the slide is in battery (or the punch is removed). With the grip safety out of the picture, I can very gently push on the right side of the sear with a punch and I hear a distinct click and the disconnector pops up just enough to allow the trigger to drop the hammer. The disconnector hole in the top of the frame had some machining marks left in it (distinct rings), which I've (mostly) polished down with some diamond files & 400 grit sandpaper on a long transfer punch. My understanding is that this is not a precise fit in this hole, in fact I can see the disconnector rocks backward a tiny bit pivoting on this top of this hole (I think). After cleaning up the hole (I can still see the rings, but they are much less pronounced than they were), I can now rack the slide (no recoil mechanism) with the grip safety out of the picture, and the disconnector will pop back up enough for the trigger to drop the hammer, but it needs a very hard pull to do so. However, if I put the grip safety in place (pin in, hammer cocked, rotate into place, depress plunger, push home), rack the slide and manually put it into battery, the hammer won't budge. I learned last night from another thread on here that I can push the disconnector so it "pops" back into battery by using a long transfer punch through the mag well (instead of partial diassembly to remove the grip safety as I'd been doing previously). It makes a much more distinct "CLICK" when I do so, but then the hammer will fall when the trigger is pulled, again with a lot of pressure.

I've played with the geometry of the sear spring by adjusting the center leg both in and out thinking there may be either too much pressure on the disconnector, or not enough.

So after all that, here's my question: should I polish the disconnector hole in the frame until I can't see any rings? Or do you even think that's my problem? Might it be the sear spring needs adjusting, maybe a combination of the two?

Theoretically all these parts should have 70 years of wear together, but I can't really state that that's true, since there's no way to know if they're all original parts (or at least no way for me to tell, I don't know enough yet). However, the geometry of the frame could be slightly off from what it needs to be, so things may not be engaging as they should.

My goal here is to have as close to one of the 1911's I trained with in the USN as I can. I'm not looking for a super light trigger pull, I'm looking to have a 1911 as you'd have received and used in the military.

Hopefully I've provided enough information for a diagnosis.
 

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If I were you I'd totally strip the frame and insert only the sear, disco and sear pin and see whether there is any binding in any way. Move the disco up and down and forward/aft in it's hole. Notice anything? Then try removing those 3 parts and slide the trigger in and re-insert the sear/disco and sear pin and try and determine where the trouble starts.
 

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Disconnector

Completely inspect the disconnector and polish the disconnector and everything that comes in contact with it.....also make sure the back of the trigger bow does not have any burrs so polish that as well.

I once had a problem with a disconnector not resetting, and it was due to a short middle finger of the leaf spring. The middle finger was not engaging the back of the disconnector high enough, and on occasion, would slip down and the disconnector would bind on the leading edge of the spring when trying to reset. I fixed this issue with a new leaf spring, and the middle finger engaged the disconnector much higher. Another issue (but rare) is the slide is out of spec. so the disconnector cut out of the slide is not deep enough...look for any rub marks on the slide cut out to see if the disconnector has been hitting anything on the sides of the disconnector cut out of the slide..... When I do a trigger job, the trigger may feel perfect with the slide off, but when I place the slide on the gun and try the trigger, I may feel creep.....sometimes this is caused by slight movement of the disconnector rubbing on the front of the shallow cut out of the disco notch on the disco rail of the slide.... I usually remove metal to deepen the disco notch.

I like to take the slide off the gun, remove the grip safety, then manually work the disconnector by pushing on it up and down from the top of the frame with the leaf spring engaging the back of the disconnector. Sometimes this may give insight on where and why the disconnector is hanging up......

If the frame hole for the top of the disconnector is oversized, I don't like a lot of lateral or sideways movement of the disconnector, since it may affect the consistency of the trigger pull....I want the disconnector to fit so it mainly travels up and down. When I encounter an oversized disco hole in the frame, I use a center punch and peen the hole smaller in the needed areas. Often times one hit with a hammer on the punch will swage the metal. If it is too tight, I simply open in up slightly with a needle file to make a better fit with limited side and front movement.
 

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With the GS out look at the bottom of the sear and top of DIS paddle when the DIS is pushed down by the slide,it sounds like they don't have enough clearance and when you push the sear it's just enough to dislodge them.When the DIS disconnects it slides back under the sear feet until you let off the trigger,then the spring pushes it back forward so it can pop back up when the slide cut allows it.It sounds like you have no pretravel in the trigger,or slightly negative pretravel.
 

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Discussion Starter · #6 ·
Thanks for all the responses, I've got some work to do after all the xmas stuff is over. I've got a few questions for some of the responses (in no particular order)
  • @rex: Can you explain what "trigger pre-travel" means, and how would I tell?
  • @richpetrone: Can you explain how you use a center punch to peen the disconnector hole smaller? Do you work from the underside to move metal from beneath hole? Not sure what would be involved to do this, and to me a "center punch" means an automatic punch like you'd use to create a dimple to drill into. Is this what you're referring to?
  • @1911rocks: I don't believe I am pulling the trigger back. Do you mean as in to it's forward position, or like you're actually pulling the trigger? I wasn't sure what you meant, and what the ramifications are in either case.
  • MGould: I'll try your suggestion.

I also plan on polishing the faces of the sear, disconnector & back surface of the trigger mechanism where the disconnector rides. I don't want to try stoning the engaging surfaces because I have no idea what I'm doing other than reading about Log's trigger job, and watching some YouTube videos. I'm hopeful that these parts have long since worn together, and only need some fitting & deburring due to the new frame they're now situated in.

Thanks again, I'll follow up with pictures and probably more questions.
 

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Pretravel is the initial "slack" in the trigger before it pushes the disconnector into the sear feet,at that point you feel resistance until the hammer falls.Some actually have free movement before the trigger bow touches the disconnector.The pretravel allows the disconnector to reset and also provides a safety margin for trigger bounce,which will drop the hammer.There should be a minimum of .040",and that's tight.

When you look in the back of the frame with the GS out,you can see the disconnector moving up and down and forward to back as you manipulate the slide and trigger.Operate the gun as it works,pull the trigger to drop the hammer and hold it back as you rack the slide,the DIS will be held under the sear feet.Let off the trigger and the DIS should pop forward and up to reset.If your pretravel is 0 or nonexistent,the trigger bow isn't allowing the DIS to come all the way out from under the sear.A short sear,long trigger bow or the top hole is allowing too much slop could be the cause.If it's the hole,moving the top of the DIS when it's stuck should dislodge it,if it's pretavel pushing the top of the sear forward will do it.Hold the hammer if you push the sear so it doesn't slip to 1/2 cock or fall.
 

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Disconnector hole on top of frame

A "center punch" is used to make a dimple..... There are automatic center punches, but I use a standard steel center punch with a good point at the tip and use a hammer to make the "dimple" in the steel. The gun has to be properly supported underneath the frame mag opening so the frame doesn't move down or laterally when you strike the center punch with a hammer. When you place the center punch near the edge of the disconnector hole, it should be approximately 1/16"-1/32"" from the edge of the hole, when you hit the center punch, it will make a dimple and swage the metal outward....so the disconnector hole gets smaller. If you happen to make the hole too small, as mentioned, a good round needle file will allow you to enlarge the hole to make a close fit so the disconnector only moves up and down.....

Attached is a photo that shows where I used a center punch to swage the hole tighter to prevent the disconnector from "rocking forward" as the trigger was pressed.....I was shooting this gun yesterday, so please excuse the "not so clean gun photo....":eek:
 

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Thank you Rex

Pretravel is the initial "slack" in the trigger before it pushes the disconnector into the sear feet,at that point you feel resistance until the hammer falls.Some actually have free movement before the trigger bow touches the disconnector.The pretravel allows the disconnector to reset and also provides a safety margin for trigger bounce,which will drop the hammer.There should be a minimum of .040",and that's tight.

When you look in the back of the frame with the GS out,you can see the disconnector moving up and down and forward to back as you manipulate the slide and trigger.Operate the gun as it works,pull the trigger to drop the hammer and hold it back as you rack the slide,the DIS will be held under the sear feet.Let off the trigger and the DIS should pop forward and up to reset.If your pretravel is 0 or nonexistent,the trigger bow isn't allowing the DIS to come all the way out from under the sear.A short sear,long trigger bow or the top hole is allowing too much slop could be the cause.If it's the hole,moving the top of the DIS when it's stuck should dislodge it,if it's pretavel pushing the top of the sear forward will do it.Hold the hammer if you push the sear so it doesn't slip to 1/2 cock or fall.
The DIS resets as you release the trigger....like Rex so eloquently states. Some folks mistake "pre-travel with creep and they "want it outta there"
 

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After carefully reading the first post by the OP where the disconnector is held down when pushed down after a "click". I agree with the diagnosis presented by Rex, that is there is little or no pre-travel. Thus when depressed the paddle of the disconnector is squeezed by the rear of the trigger bow, forcing the paddle of the disconnector slightly under the lower legs of the sear. This could be caused by a short sear allowing the lower sear legs into the path of the disconnector. The trigger bow could also be a little long. It could be as simple as a loose sear pin in the frame. The paddle of the disconector could also be thicker than specified.
 

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Measure the distance from the sear spring slot in the frame and where the spring rests on the disconnector. You can do this visually to determine that the sear spring middle finger rests at the correct height. This measurement is critical and may cause these symtoms. This is a common issue with frames that are not machined, drilled and milled to Colt spec's! A longer sear may be required to get this measurement correct or filed shorter if too long.
 

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If the internals are truly G.I. parts, then I would expect every one of them to be within spec, unless overly worn. That is, unlikely that the trigger is too long, the sear too short, the sear spring too long or too short, etc. I'd be focusing on the frame, hole locations in particular.
 

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Unfortunately the OP has neglected to respond to some thoughtful reply's to the problem he has presented to us. Too bad.
 

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Discussion Starter · #14 · (Edited)
Unfortunately the OP has neglected to respond to some thoughtful (sic) reply's to the problem he has presented to us. Too bad.
Unfortunately sometimes life gets in the way of hobbies.

If the internals are truly G.I. parts, then I would expect every one of them to be within spec, unless overly worn. That is, unlikely that the trigger is too long, the sear too short, the sear spring too long or too short, etc. I'd be focusing on the frame, hole locations in particular.
Thanks for all the input and advice guys I appreciate it. I was finally able to solve the disconnector problem. The machining marks in the frame turned out to be the culprit. Over a period of several nights I slowly stoned down the ridges in the hole until it finally worked. Once I got it to where it worked reliably I stopped. As long as it's working, I figure it'll wear in over time instead of me damaging the frame with a file or stone.

I can still see the ridges in the hole, but they're much-much smoother than they were before, and the gun is working as it should. I haven't had the opportunity to shoot it yet, but I did take it to a friend's house yesterday who shoots competitively and ran some snap caps through it to check functionality. We tested the trigger pull to a consistent 6lbs. I'll only load a round or two at a time to test fire it when I can get to the range to make sure it's truly functional. I have high hopes for it, and I like the way it turned out.

Here's what it looks like all put together:

 

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Please size your pics to 800px X 600px max.

LOG
 

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Post #11

"A longer sear may be required to get this measurement correct or filed shorter if too long."

Should read:

"A longer sear SPRING may be required to get this measurement correct or filed shorter if too long."

Sorry,

John
 

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...Here's what it looks like all put together:

That thumb safety is not a GI part. The casting marks are obvious on the outside of the flat shield. That does not mean that it cannot function perfectly well. It just calls into question whether your other parts are truly GI (and of GI quality). The SARCO sourced parts have a generally poor reputation and can cause problems with fit or function. Just be aware of that and plan accordingly.
 

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Maybe its just the lighting, but that short trigger looks really short.
 

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Discussion Starter · #20 ·
Photo resized.

Regarding the thumb safety, I agree with you. I think it's a mix of old & new-ish parts, and while that particular one is pretty obvious, I don't know enough about Colt 1911s to be able to identify non-Colt parts. The last time I field stripped a military Colt was in the early '80's, and I don't recall any specifics. You can also see that the sear pin is "in the white" (I think that's the term?), not blued or Parkerized, so it's almost certainly not original.
 
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