View Full Version : 1911 bending sear pins during dryfire!
February 26, 2002, 01:10 AM
Okay, I'll admit it.
After 20 years of working on 1911A1 pistols, I thought I'd seen it all.
Now my old warhorse is sick and I can't figure it out.
During an IDPA match weekend before last, I pulled the trigger on the first shot of a double tap and the hammer caught on the half cock notch.
It functioned fine for the next 20 rounds or so, then did it again.
When I got home, I tore the pistol down and found a bent sear pin. Thinking that this was the source of my problems, I replaced both the sear and hammer pins. (Figured if one was worn out, the other probably was too.)
I then took the pistol to the range for a day of shooting.
It did fine for the first 200 rounds or so, then started dropping to the half cock notch again. I tore the pistol down and sure enough, the sear pin was bent again!
I replaced it one more time, and in the course of 3 or four dry fires, it began dropping to half cock yet again!
Sure enough, another bent sear pin.
I've been shooting this pistol for almost 15 years. It's one I built myself while in the Corps. Essex frame and surplus slide.
The pistol is set up tight.
Very little takeup in the trigger, and the over travel was set in to "won't fire" then backed out one turn.
I'm completely stumped.
The hammer looks good, the sear and disconnector look good, and the trigger appears good as well.
February 26, 2002, 08:38 AM
Ken, I don't know why they do it but it's not the first one I've seen or heard about. I do have a theory. I think that sometimes the pin holes in the reciever are slightly misaligned. I have had 2 in the shop for the same problem this past year. With both I reamed the holes straight and installed Marvel oversize pins and as far as I know neither gave the owners any more trouble. George
February 26, 2002, 09:06 AM
I could understand that if this were a new gun, but I've got more than 50,000 rounds (much more!) through it with nothing more than a lost front site up til now.
February 26, 2002, 08:18 PM
Ken, My first 1911 was a parts gun on an Essex frame, and has given me good service these many years. You mentioned that you have the overtravel screw on the trigger set pretty precisely, and that could mean that the nose of the sear is getting hit by the edge of the half cock notch as the hammer falls. Without the overtravel screw, the trigger's rearward clearance would provide more clearance for the half cock notch to miss the sear. You might try backing out the overtravel screw a little further and trying again with a new sear pin. Good luck.
February 27, 2002, 12:06 AM
I have to ask where you are getting your sear pins. They should be hardened tool steel and not very easy to bend, but as with everything else, a lot of the modern parts are made to look good and sell, not stand up to use.
The sear pin takes some beating in the normal action, as the hammer comes down on the sear when the slide goes forward, so it can't be too weak, but I can't think of anything that could bend it. I don't know about the Essex frame, but in the GI frame the sear pin is very well supported at both ends and I can't imagine how it could possibly bend.
I don't think that the hammer brushing the sear would have enough force to bend that pin, nor would normal finger pressure on the trigger.
Let us know what you find out.
February 27, 2002, 12:47 AM
The question about the over travel stop is a valid one, but one that I've already positively ruled out. Besides, 1 full turn isn't that tight of a setting.
This wasn't my first 1911 by far, and I've got several more of differing make and size, but this one is "special" to me.
I qualified Pistol Expert with it several times, it's done very well for me in matches, and of all the guns I own, when I want extreme accuracy, this is the one I reach for.
If I were ever given the choice of only one gun for the rest of my life, it would be this one.
This is why I'm so disturbed at George's post.
I just can't understand why this pistol has performed so suberbly and accurately for so many years and so many rounds, and now it just won't WORK!
Jim Keenan mentioned the possibility of defective sear pins, and I had considered it myself and then discarded the idea. The pins are supposed to be good, but one never really knows sometimes.
I'll have to find some pins of known quality and give them a try.
Otherwise, I'm probably going to end up with a nice paperweight with a lot of memories and sentimental value attached. That's just unacceptable.
On reflection, it seems to me that it almost has to be the sear pins themselves.
The frame pin holes were obviously okay for 15 years, so if the hole "wore out" somehow, it did it awful fast.
I'll let y'all know as soon as I find out.
Who's "Da Man" for quality pins these days?
Btw, Hi Jim, nice to see you again!
February 27, 2002, 02:14 AM
Hope you can find a solution. I guess I'm paranoid about overtravel screws, since I know of two situations where they caused problems in competition. I like the long triggers, but don't use the screws. I once had a long trigger fitted to my Essex frame, and I recall the gunsmith commenting on the tolerances being a little different on the Essex. Of course, this doesn't explain the great service you've had from your 1911 up to this point. Good luck and keep us posted.
February 27, 2002, 02:56 AM
Gota go with Jims post on this one,
Think Id have a hard time bending one chucked up in a vise.
Check your hammer and sear very close ,with a glass
if the hammer has fallen several times , its gotta be
beating your sear.
Possible the trigger rear travel is not moving the sear
completely clear of the hammer, and the hammer is
partially striking sear each time it falls.
Hold the hammer back, pull the trigger, slowley roll the
hammer forward , to see if you can feel it bump the sear.
KINGS stocks a slightly oversize hammer sear pin set
around 8 bucks I think.
Best luck JB
February 27, 2002, 11:16 AM
Ken..Think about how long you been shooting that 1911..It's an Essex frame..Grant you one of the better and affordable frames but even they wear out..I suspect that just possibly the searand hammer frame holes may have just worn a bit more than say a forge frame..Before getting so frustrated and retiring it, pay a few bucks and get the sear pin hole checked for aliagnment and if necesary fixed with over size pins..If you love the gun like you say you do..a few bucks to fix will be rewarding. Good luck!
:cool: :cool: :cool:
February 27, 2002, 10:41 PM
I no longer have an Essex frame, having sold the last one I had. But on the GI frame, the sear pin is supported on both ends such that only the center 1/2 of the pin is exposed, and that is just enough for the sear. The gap at that point is only a bit wider than the sear itself, so the pin would almost have to shear to bend unless it were very soft.
If the holes are not expanded, and the frame is intact and supports the pins as I said, then I can only again look to the pins themselves. Maybe a simple file test would show if they are hard enough.
March 2, 2002, 01:44 AM
Have you ever gotten so wrapped up in a problem that you can't think straight????
That's where I'm at with this thing now.
Trouble shooting has progressed as such...
1. Got a sear pin from a different batch, the bent pin problem ended. Needless to say, I tossed the rest of that batch in the garbage.
The reason the first pin bent was because the original sear pin had broken. I didn't think anything of it (and still don't) as it was the pin that I put in the gun when I first built it. (I replaced the hammer pin at the same time, just to be safe.) So that was the first sear pin of the "bad lot."
2. The gun falls to half cock every single pull of the trigger now, but at least the pin's still straight! :rolleyes:
3. REMOVED over-travel stop, it made no difference.
As I said, the hammer's still falling to half cock every time. I can't figure it out to save my ass.
March 2, 2002, 08:04 AM
Ken, I think you need to adjust your sear spring. You may have too much tension against the sear or not enough against the disconnector. George
March 2, 2002, 06:28 PM
Wow, Ken. Thanks for keeping us current on this and hang in there. Have you had a chance to check the sear and hammer engagement surfaces under magnification?. Just wondering if the sharp corners of those parts may have become rounded. How quickly do you release the trigger to let it reset? Does the hammer follow to half cock if you drop the slide to chamber a round with the slide stop? Sorry for all the questions, just trying to see if any pattern developes.
March 2, 2002, 11:47 PM
With all other parts removed, check to see that the sear is free to move on the new sear pin. If not, some fitting needs to be done, either on those parts or on the frame.
If the sear is free to fully engage the hammer notch, and the spring tension is correct, then either the sear or the hammer is worn or battered and will have to be replaced. (Both hammers and sears can be recut and rehardened, but it usually is just not worth it.) Buy good ones from Brownells and you might find you still have a good trigger pull.
March 3, 2002, 12:29 AM
I built a 1911 on Essex frame and slide, I was buying all the cheap
parts, I was having the hammer fall half cock allmost every shot,
but I found that the grip safety which was a cheap sloppy Colt was the reason,the Colt safety was not long enough to engage
trigger and sear, tried peening it longer and just ended up with a mess, bought a better grip safety, and stoned the sear and put a better trigger in and the gun fired fine, seems the grip safety was slipping off trigger and sear wasn't letting hammer drop all the way.with all the rds you shot it you might check the grip safety
end where it engages the other parts, ?
March 24, 2002, 01:25 AM
I'd already considered that one and tested it with the grip safety removed.
Made no difference.
Tried that too.
I've also tried replacing the hammer and sear, so it looks like George is right. It's pretty much got to be the sear pin hole just worn out of spec.
It looks like I'm going to have to go with the over-sized sear pin.
That being the case, the pistol will be retired to a place of honor and only brought out for occasional shooting.
I guess it's time to start building up that Les Baer matched Frame and Slide I've been meaning to get around to. (It's been sitting in my safe for a year.)
I won't weep too much, but when I do, I'm going to have something very special to console myself with.
Thanks everyone for the extra heads on the problem.
I appreciate it.
Thanks George, it wasn't the news I wanted to hear, but at least it was accurate.
March 24, 2002, 01:28 AM
I just saw George's post about the sear spring.
Now that I think about it, that sear spring looks awfully far forward. (Damn, could it be that simple?)
Hope dawns anew!
I'll let y'all know.
February 18, 2005, 11:17 PM
I had the exact same problem in a new built Essex frame pistol. If you haven't solved your problem, here is what stopped mine. It turns out that the disconnector was not securely engaging the sear. When the trigger was pulled, the disconnector would slip under the sear, and drop the hammer to half cock instead of firing the gun. If the pin was hardened, it would break, if not it would bend. I replaced the disconnector, and the pin is still OK after 300+ rounds. Hope this helps!
February 19, 2005, 02:30 PM
WE have finally noted that the disconnector is in the center of the sear pin. The sear is on each edge of the pin, not the center. Your trigger job has gone bad. Dropping to half cock may be corrected with a NEW sear spring or it may not. Something is wrong with the hammer hook/sear engagement and the Essex lower ends were not the best, to put it kindly. I worked on one many years ago and that was enough for me. I think you need a new hammer, sear, and disconnector and new springs all the way through the gun. It is not the over travel screw because you checked that. I like overtravel screws and have them in all of my 1911's. I set them up and red loctite them in and forget them.
I have heard that Essex lower ends and slides are much better now.
February 20, 2005, 01:35 PM
:o :eek: I am TOTALY blank! :o
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