Gold Cup Follow Down

Hello Folks,

 A friend showed me an unusual malfunction yesterday. His Gold Cup allows the hammer to follow the slide when the magazine is empty. It stops on the half-cock notch. As long as there is ammo in the magazine the hammer remains cocked after the slide cycles. He has taken to loading an empty case and then five cartridges. That way he can shoot strings of five.

The malfunction only occurs when the magazine is empty.  It occurs with all magazines (we checked).  It happens whether hand cycling the gun fast or slow, or when firing. 

I suppose the magazine follower must be touching the disconnector when the magazine is empty, but neither he nor I can see how. Also, he let me shoot this gun a couple of months ago and it functioned normally then. Something changed

Have you seen this malfunction before? Can you suggest a cure?

Thanks, Tom

the only way I can recall a magazine having any bearing on the trigger (except for the mag disconnect, which a GC does not have) is if the trigger stirrup drags on the magazine,
would doubt a loaded mag would make a difference if it did vs an empty mag,,

there is no way for the mag follower or slide stop to contact the disconnect or sear,

is the gun clean?
sear spring (which puts pressure on the disconnect as well) within spec?

for giggles, does that happen with each magazine?

It occurs with all magazines.  It happens every time.

Disconnector can make contact with rear of magazine through the frame opening.
If you hold to trigger to the rear and release slide does it follow? With and without magazine inserted?
Jon

Why is the slide not staying back? You would not need an empty case if slide stayed back. You would only be releasing slide when it was loaded and ready to chamber a new round. My SA drops to a half cock when closing slide on empty magazine but I have the trigger set at 2.5lbs. (38 super). I know I could solve it if I wanted to increase trigger weight. It doe not follow if released slowly though.

Len

The magazine is empty when the last round is chambered.  When the last round is chambered the hammer follows the slide.  If the hammer is then manually cocked and the last round is fired, the slide will lock back normally.

Another place to check is to see if you have too little sear spring pressure on the trigger or sear finger.  You should check how the pressure is distributed between the spring fingers with a trigger gauge.

Unload gun, remove the grip safety and reinstall the other parts so the gun is functioning again.  Rack the gun, and actuate the trigger with the trigger gauge and remember what the total pull is.

Rerack and pull the trigger with the pull gauge again, but not all the way.  Watch the back of the trigger frame and stop pulling at the point just before the sear starts to move.  This gives you the weight of the trigger/disconnector finger of the flat spring.

Subtract the trigger spring finger weight from the total trigger pull weight and you will know the weight on the sear spring finger.

You can modify these weights for different feel, but for now, start with a close to 50/50 ratio. So for a BE trigger of 3.75 lbs, you may want 2 lbs on the trigger and 1.75 lbs on the sear.

When you have hammer follow issues, you may find that you have .5 lb on the trigger spring finger and 3.25 lbs on the sear spring finger or vice versa.  This is a sure recipe for sear bounce or hammer follow, which is caused by not having enough spring pressure for the parts to stay where they are supposed to be during operation.

Your weights may be on the edge of correct function.  The hammer or sear is fine with the slide slowed down by upward pressure from a round in the magazine dragging against the slide, but when the mag is empty there is enough momentum and vibration to cause the hammer to follow.

It’s all well and good that folks trust the half cock to catch the hammer, until it doesn’t and the gun doubles or fully unloads automatically.  The half cock notch may be damaging your sear nose as well, messing up your trigger job (although I think the Gold Cup has the 1/2 cock notch machined to prevent this type of damage to the sear).

There may be other causes as well, but I start with adjusting the spring fingers to similar weights.  Later, you can work with these weights to cause changes in the trigger feel once you know what to look for and how to set up and test for safety.

Not sure if this will help, but is a good place to start.

@Len, my 1911 .22 conversions have been set as low as 2lbs. and have no issue with hammer follow, even with the .45 slides on them after doing the preceding tests to make sure that one of the fingers is not set too lightly.  The adjustment should keep your trigger weight the exact same as it is now.  It just changes how that weight is distributed.

What series is the gold cup

You may wish to check the following...double check that you have a correct slide stop...it should read 1 on the inside.  Also, you may need to adjust the sear spring a little to ensure that the hammer does not follow the slide...

Hiya,

It's called "following". All 1911's will do it on an slide drop on an empty chamber if there is not enough sear spring pressure or the sear notch/face are damaged/have been cut on the wrong angle with an novice trigger job. 

What happens is that with no round to slow the slide, the slide impacts the barrel hood and locks up at full speed, this sends a shockwave into the frame that "bounces" the sear out of the full cock notch, thus allowing the hammer to "follow" the slide.

Being a GC, there "should" be an additional sear pressure spring to prevent bounce, if it's following, I suspect it was left out as they are a PITA to put together if you don't know the trick.

tomd999 wrote:Hiya,

Being a GC, there "should" be an additional sear pressure spring to prevent bounce, if it's following, I suspect it was left out as they are a PITA to put together if you don't know the trick.

Hello tomd999,

Newer Colt Gold Cups do not have that spring.  They were phased out when Colt transitioned triggers from steel to aluminum.

Jim

The sear bouncing out from under the full cock hooks is because of the inertia of the trigger, not the direct shaking of the sear.  When the frame is "shocked" forward by the slide, the trigger tries to stay in its position in space, causing it to apply pressure on the sear via the disconnector.  If the disconnector is out of the way because the trigger is held back, the hammer will not follow, unless there is extreme damage to the hammer/sear engagement.

Why would this explain the malfunction only when chambering the last round in the magazine?  If the gun is loaded with six and five are fired it does not follow down.  If five are loaded and five are fired, the hammer follows the slide after the fourth shot

Boxturtle wrote:Why would this explain the malfunction only when chambering the last round in the magazine?  If the gun is loaded with six and five are fired it does not follow down.  If five are loaded and five are fired, the hammer follows the slide after the fourth shot

 
Hello Boxturtle,

It doesn't....there is not enough information given by the OP to diagnose the problem.

Jim

Boxturtle wrote:Why would this explain the malfunction only when chambering the last round in the magazine?  If the gun is loaded with six and five are fired it does not follow down.  If five are loaded and five are fired, the hammer follows the slide after the fourth shot

Ah, indeed!  I was not actually addressing the OP, but the erroneous suggestion that closing on an empty chamber shakes the sear loose from the hammer, without taking into account the trigger inertia, which also wasn't addressing the OP's issue.

To the OP, now that I am involved in the thread, I have not witnessed this.  I will put some thought into it and see what "far-fetched" ideas form...

Ed Hall wrote:...  I will put some thought into it and see what "far-fetched" ideas form...

I came up with many that were too far to be of merit.  I did come up with one that although really remote, may have a tiny bit of credence:

If the trigger over-travel is adjusted too close, there is a very slight chance that the disconnector is able to just barely catch enough of the sear (or its extra part in early Gold Cups) to drop the hammer.  The reason it only manifests on the last round is the different drag on the slide, whether it rides a follower or a round.  I would try one-quarter turn CCW on the over-travel screw to test the idea.

Sorry if this has already been addressed and I missed it.

If any other odd thoughts come to mind, I'll post them later on.