[willbrink]

My Colt series 70 is giving me a malfunction starting this morning:

After each rnd fired, the hammer is going to the half cocked position, vs the fully cocked position. Changing ammo or mags didn't have any effects. Working the slide on an empty gun, gets the same thing: hammer is going to half cocked position vs fully cocked.

Gun is not dirty, mags and springs all fairly new, not a terribly high rnd count gun, probably 12-15k.

Looks like this gun will need a trip to the smith. :(

[rcmodel]

Very likely a sear spring arm is bent too light, or broke off completely.

12K - 15K rounds is a lot if the gun has never been detail stripped and cleaned internally.
If you know how to detail strip a 1911, this would be a good time to do it.

Check for a binding trigger bow, chipped or deformed sear or hammer hook edges, or a warped or broken sear spring.

rc

[Badger Arms]

+1, especially true of guns that have, at one time or another, had a 'trigger job' done.

[willbrink]

I have not detailed stripped the gun. I generally field strip,soak them in dunkit, scrub them, lube them, put back together. I guess I should try a detailed strip. Never done one before, but I have a few CDs, etc on how to do it. :o

[loadedround]

In my opinion it could only be one of two things causing that to happen. First a bad sear spring or a damaged or broken sear. I would start by replacing the sear spring with a new one before tearing down a Gold Cup to check the sear itself. Reassembling that GC can be a royal PIA until you learn the tricks of using slave pins. :uhoh:

[RogersPrecision]

Will,
You have not had much luck with the 1911, have you?
Might be time to find and use a 'competent' 1911 smiff.
:scrutiny:

[willbrink]

"Will,
You have not had much luck with the 1911, have you?
Might be time to find and use a 'competent' 1911 smiff."

Is that an offer Mr Rogers? What's your wait list these days, 5-6 years? :evil:

Yes, this is one of 2 guns that were done by a smith I no longer use. The person I have been using recently seems to know his sh&$, and I will probably go see him this weekend to fix it. I did detail strip it, put it back together, and it's slightly better, but not fixed I didn't see any obvious wear that would explain it, but I am no smith. BTW, I noticed the trigger is also very light now, which I just noted and I am sure is connected. Trigger was 4lbs, feels more like 1-2lbs now.

[willbrink]

I changed out the sear spring, and if anything, made it worse. So the sear, or geometry, etc is out of whack. That's beyond my fixing knowledge, so I will have to get it looked at.

[Kruzr]

A sear spring is not a drop in part. You must adjust the sear spring by bending the arms. Does the hammer follow if you hold the trigger back while dropping the slide?

[willbrink]

Hold the trigger back while dropping the slide? I dont follow. Pull the trigger = hammer dropping right?

[10X]

You are receiving the correct answers.
The sear needs more tension from the spring. Bend the left leg (oriented as if in firing position) of the spring just a little more.

Reassemble.

Pull the trigger and keep it pulled. Pull the slide back and release it so it slams home. If the hammer doesn't follow, you have enough tension.

As also stated you should check the hammer and sear engagement.
Pull the hammer back. Push the hammer moderately, not hard, with your thumb. If the hammer stays put, you have plenty of engagement. If the hammer does not stay put, you have to either replace the hammer or sear or have a good smith work on the hammer and sear. This is a job for someone that knows what they are doing.

[willbrink]

Did the above. Pushing on the hammer, it does not fall. Adding tension to the sear spring, does not improve the situation however. Hammer still falls forward to half cocked position. Trigger pull is also very light, which I assume must figure into this some how too. :cuss:

[rcmodel]

not hard, with your thumb. If the hammer stays put, you have plenty of engagement.Pushing on the hammer is not an indication of "plenty of sear engagement".

I have seen a lot of them you could push till your thumb fell off that didn't have plenty of engagement, and would follow the slide down.

The gun in question sounds like a damaged sear or hammer hooks, or both. Sear edge angle, or break edge is set up wrong or just worn away. Or the hammer hooks are cut or worn too short.

It can also be related to the disconnector or trigger bow.

It's time to find a gunsmith.

rc

[willbrink]

So it would appear...:o

[willbrink]

I did the above, and could not find the cause. I tried a new sear spring for shi%& and giggles, adjusted tension, and got no improvements. So, it seems like a possible damaged sear or hammer hooks, or both, or perhaps the hammer hooks are cut or worn too short, etc, etc.

So, what I did was order a complete kit from CYLINDER & SLIDE:

"Each kit is tested on a Series 70-style frame to make certain it will produce the specified pull weight with little or no fitting."

As written "All profiles and through-holes are mechanically correct to function without hand fitting. Sear nose has correct relief angle, sear spring is narrowed to reduce pull weight. Exposed hammer edges on Ultra-Light, Super Match and Tactical II are chamfered to minimize slide drag and clothing wear. Each kit contains a hammer, sear, disconnector, sear spring and hammer spring."

I ordered the "TACTICAL MATCH KIT - 4.5 lb. pull weight. Tactical hammer, sear, disconnector, light pull sear spring, 18 lb. hammer spring."

I know, I know, "drop in part" is an inside joke with 1911s, but I need to learn this stuff anyway, and I figure the above kit will at least give me a head start.

Have I set myself up for frustration? Possible, but C&S is a fine company as we all know, and all of it coming from one quality company increases the potential it will all work together, and I may need to either learn how to do a small amount of fitting or hand it over to the smith for installation after I give up!

Either way, I have wanted to learn this stuff for a while, and this is as good as any time to try it and the right gun to learn it on. I may be looking for help/tips in the future...

[rcmodel]

You shoulda bought the book.

http://www.brownells.com/.aspx/pid=13805/Product/JERRY_KUHNHAUSEN_THE_COLT_.45_AUTOMATIC

rc

[willbrink]

Well I guess that will be next, especially if the kit I purchased does not "drop in" as claimed.

[loadedround]

Willbrink: I would strongly advise you to take a close look at a Colt Gold Cup schematic before you tear down your pistol to install your new parts. You will find several "little extra sear parts" in the Gold Cup that are not present in other Colt 1911's. You will not, I repeat, will not, be able to reassemble your pistol w/o knowing the "tricks of the trade". I will not try to explain here, but the trick is to use a disposable slave pin upon reassembly. I speak from personal experience. :cuss:

[popeye]

Can't you buy a wide aluminum GC trigger and eliminate the additional sear parts? It's been a while but I seem to remember doing that.

[willbrink]

Follow up: the above kit from CnS worked out perfectly. If one can detail strip their 1911, they can install this kit from CnS. Trigger is a crisp 4.5lbs, and the gun has been great so far. Yes, it replaces far more then was (probably) needed to cure this problem, but I enjoyed the learning process there and hope to learn more minor gun smithing skills in the future. This kit from CnS gets a thumbs up from me at least.