PDA

View Full Version : 1911 hammer drops to half cocked


Reconinforce
August 20, 2016, 19:14
1943 Remington Rand 1911

Periodically drops to half cocked when dry firing.

Took out grip and manual safetys and it still does it.

When I ease the the hammer down I can feel it rub/catch a bit mid way through. Not always and I can make it malfunction more when really squeezing the grip safety.

Can't really narrow it down.

Any ideas? I'm going to try swapping parts with another remington Rand later and try to see what removes the problem.

L Haney
August 20, 2016, 19:25
From your description you are not really familiar with the fire control of a 1911. Nothing wrong with that, most people aren't.

I'd suggest you employ the services of a professional at this point.

My reasoning on this is I want you to have a pistol that operates to spec. Lot going on in there and it don't need to incorporate any aspect of maybe.

Reconinforce
August 20, 2016, 19:36
Lol well that helps.. Haha.

I enjoy the problem solving side and have worked on a lot of different guns in the past. Always able to resolve the problem at some point. I'll try do eliminate this problem and find out which part or parts are causing the issue.

I'll use a smith as a last resort but I'll figure it out most likely.

If anybody had this before and fixed it let me know.

L Haney
August 20, 2016, 20:18
Lol well that helps.. Haha.

I enjoy the problem solving side and have worked on a lot of different guns in the past. Always able to resolve the problem at some point. I'll try do eliminate this problem and find out which part or parts are causing the issue.

I'll use a smith as a last resort but I'll figure it out most likely.



Not trying to discourage you from learning this handgun. Not at all. But I'd strongly suggest enlisting some help from somebody knows it inside and out.

Remote trouble shooting on the web with this issue is problematic. Wish I were close, I'd be glad to come over and we'd sit down with the thing and go though all of it.
Just like was done with me.

Invictus77
August 20, 2016, 20:29
Remote trouble shooting on the web with this issue is problematic.

^^^^
This is a fact...

<iframe width="420" height="315" src="https://www.youtube.com/embed/4P4XJTKzKEU" frameborder="0" allowfullscreen></iframe>

ICOM7800
August 20, 2016, 20:36
1943 Remington Rand 1911

Periodically drops to half cocked when dry firing.

Took out grip and manual safetys and it still does it.

When I ease the the hammer down I can feel it rub/catch a bit mid way through. Not always and I can make it malfunction more when really squeezing the grip safety.

Can't really narrow it down.

Any ideas? I'm going to try swapping parts with another remington Rand later and try to see what removes the problem.

Bend Your Sear Spring. Its tired.Been there done that.1944 Colt 1911A1 .

ICOM7800
August 20, 2016, 20:40
Take off your mainspring housing.The sear spring lies underneath. Either bend the offending finger on spring or replace it .

medicmike
August 20, 2016, 20:41
Cool video Invictus!

It sounds like there is some sort of interference in the sear/hammer engagement, if you have the parts to swap that would be where I would start.

I agree with the above posters, hard to TS over the net. I am no 1911 expert but I have owned and been shooting them for 30+ years.

L Haney
August 20, 2016, 20:48
Take off your mainspring housing.The sear spring lies underneath. Either bend the offending finger on spring or replace it .


Do you realize what you just suggested? That spring has three fingers. You suggested something that makes no sense, is vague in the extreme, and could well be dangerous.

Why would you do that?

Reconinforce
August 20, 2016, 21:05
Thanks guys. I've got the mechanics and assembly items etc..down.

I've owned and worked on a few modern 1911s but this is a fun new challenge so I'm going to tackle it.

I've got 2 more 43,45 coming and will try out parts swaps (one at a time, keeping track of the donor gun..) and see how that goes. No danger as I'm not shooting it till all items test out and run like it should.

I understand about the online troubleshoot.. Just figured I would check before spending much more time on it in case it's a common issue.

Thanks again.

SWOHFAL
August 21, 2016, 01:06
Buy a copy of Kuhnhausen's 1911 shop manual. Be very careful with this pistol even after fooling with the sear spring, which I might go ahead and replace. You could, theoretically, get it to go full auto if the disconnector has an issue as well and that would be almost uncontrollable, so dummy rounds and no more than three live rounds are the order of the day. I'd also clean the action so nothing is sticking from old lube having gotten tacky.

Reconinforce
August 21, 2016, 07:11
Good tip. I usualy only do 1-2 in a mag when first firing after any work or changes to the internals. I also do this with new shooters learning lol

Methane
August 21, 2016, 08:09
1943 Remington Rand 1911

Periodically drops to half cocked when dry firing.



Has "someone" done a trigger job on this 1911 and ground the hammer / sear engagement faces?

Reconinforce
August 21, 2016, 09:13
Lol. No I would not jack with a wwii 1911... That would make my die inside a little. Before I bought it who knows but it looks fairly untouched since rebuild at RIA

Bug Tussell
August 21, 2016, 09:27
I had a pre 80 Commander that would fall from half cock occasionally when the trigger was pressed.

I became a fan of condition three carry and also became a fan of pistols with decockers because of this.

Methane
August 21, 2016, 10:36
Lol. No I would not jack with a wwii 1911... That would make my die inside a little. Before I bought it who knows but it looks fairly untouched since rebuild at RIA

On early hammers, half cock position has an extended portion or hook that extends over the notch and traps the sear. Later hammers, half cock position is more like the full cock notch being just a 90' notch. It is possible, while on half cock that someone pulled heavily on the trigger and deformed the half cock hook and maybe the sear as well. It is possible, measured from the hammer axis, that the half cock hook radius is now deformed and stretched out farther than the full cock radius. You got any calipers to measure those two radii, the hammer axis to outside circumferences?

Early Hammer > https://s16-us2.ixquick.com/cgi-bin/serveimage?url=http:%2F%2Fwww.brownells.com%2Fuser docs%2Fskus%2Fp_555103010_1.jpg&sp=7bcbd5f3d3a8b8a03ab55611c6274797

Reconinforce
August 21, 2016, 13:08
Yes I do. I'll check it out when I get home.

bouncer50
August 21, 2016, 23:44
Buy a copy of Kuhnhausen's 1911 shop manual. Be very careful with this pistol even after fooling with the sear spring, which I might go ahead and replace. You could, theoretically, get it to go full auto if the disconnector has an issue as well and that would be almost uncontrollable, so dummy rounds and no more than three live rounds are the order of the day. I'd also clean the action so nothing is sticking from old lube having gotten tacky. About 30 years ago i was standing next to my friend shooting a new Colt 45 auto the gun went full auto and he lost a finger. So be carefully :eek:

gunplumber
August 22, 2016, 07:47
Increase the rake of your sear angle, recut your hammer notch, increase tension on sear arm of spring.

If it follow on dryfire, you have serious issues. Should be able to hold trigger halfway and snap that slide soundly with no follow ever. Even passing dryfire is no guarantee it won't follow on live fire. But if it follows on dryfire you are guaranteed it will live.

ICOM7800
August 22, 2016, 15:41
Do you realize what you just suggested? That spring has three fingers. You suggested something that makes no sense, is vague in the extreme, and could well be dangerous.

Why would you do that?

Well when Jim Clark was alive ,I lived down the road from Clarks Custom Guns and he did exactly that to my Colt 1911A1 to cure that exact same thing.

ICOM7800
August 22, 2016, 15:51
In other words it is most likely a weak sear spring.Doing what I suggested will most likely fix the hammer drop providing sear hammer engagements arnt too worn.No nothing dangerous.However sear spring will have tp be replaced at some point.Try it and see if that helps.

gunplumber
August 22, 2016, 15:51
Well when Jim Clark was alive ,I lived down the road from Clarks Custom Guns and he did exactly that to my Colt 1911A1 to cure that exact same thing.

Not sure it's a bad answer. The sear arm of the spring COULD be preventing the sear from fully engaging, but I'd place the probability pretty low. I would deal with the sear angle/sharpness and hammer notch depth/sharpness first. Only after insuring these are correct, would I address the spring.

Reconinforce
August 22, 2016, 16:53
Thanks guys. I'll be trying out some of the suggestions.

May just start with a new spring as those are fairly low cost and i think it may need one anyway.

Wildcat
August 22, 2016, 21:02
Not sure it's a bad answer. The sear arm of the spring COULD be preventing the sear from fully engaging, but I'd place the probability pretty low. I would deal with the sear angle/sharpness and hammer notch depth/sharpness first. Only after insuring these are correct, would I address the spring.

I second the motion.

If you looked at the sear or the hammer, would you know what surfaces to inspect?

The issue -could- be the sear spring (unlikely) but if the problem is a worn sear (or hammer), bending the sear spring will temporarily cover up a problem rather than solve it.

See if this helps:
http://i536.photobucket.com/albums/ff327/ewgewgewg/searangles2.jpg

hueyville
August 24, 2016, 06:05
The trick to diagnosing is multifold. First is some experience with the system and second is having a selection of new parts that have never been monkeyed with. I keep enough 1911 internals on hand to totally build a pistol from scratch. That said, can take a complete set of new "drop in" parts and have a nightmare going off in your hand. Like many have suggested would look at the sear spring first. Have seen so many sear springs installed with a finger tucked out of position or entire spring canted. This is a wear item and needs to be replaced occasionally anyway. Carefully swap in a name brand sear spring and see where you land.

When working on 1911's and swapping parts on a trial and error basis then first remember to be carefull. Some pistols just taking apart and reassembling will cure a glitch, some require one part and some an entire fire control system. As each trial and error step is taken load three magazines. One round in first, one round followed by a snap cap second, two live rounds in third. If first fires properly and slide locks back then put in number two. If fires and snap cap loads without hammer following slide the insert three and if get to proper firings followed by slide locking back am moving correct direction. Lock the slide back several times with pistol unloaded and drop slide to see if hammer follows slide. If can't make it happen empty then ready to load up a few magazines with three to four rounds and see where you land.

The way different parts interact inside a 1911 is almost a mystery but not vodoo. If have a spare hammer, sear, disconnector and others can try a part at a time. This is not gunsmithing but swapping and praying. I would replace all springs and an entire small parts/pins kit while cleaning and making sure is assembled correctly first. If springs and pins don't do it, order a full set of internals and do the trial and error and hope you solve the issue. May be two parts not interacting properly together. Have built and repaired a lot of 1911's. They can be finicky and make no sense why acting up. If want to do this yourself will be good learning process and will have a nice collection of spare parts when job is finished.

If new to this buy name brand "drop in" parts and remember there is no true drop in on all 1911 parts, sometimes a part has to be hand fit. On some older guns have pulled hair out till finally replaced all the pins and other small parts. If the pins all have significant wear, the rest of the parts won't work properly together. Good luck and if all else fails, order a cylinder and slide prefit fire control parts set and drop it in. Expensive but works. Parts swapping can cost way more than a trip to the smith but if want the self satisfaction, it is at least an interesting endeavor.

gunplumber
August 24, 2016, 07:42
Hacks use trial and error. Professionals use
'in spec" and "not in spec".

Reconinforce
August 26, 2016, 19:37
Well boys and girls.. A new sear spring fixed her up. Hammer/trigger working just like it should.

ICOM7800
August 26, 2016, 21:26
Glad You got it working correctly.

SWOHFAL
August 27, 2016, 21:46
Well boys and girls.. A new sear spring fixed her up. Hammer/trigger working just like it should.

Still wouldn't trust it without lots of dryfiring and slide releases on dummies and limited loading of live rounds, maybe a few drops from head height onto carpet to see if the hammer drops.

Reconinforce
August 27, 2016, 22:18
Yep. I'm still testing her out but she's been perfect since then. Thanks again.