1911 Sear/Hammer Issue

[WI Birdhunter]

Hi All,

First time poster, long time lurker. I've recently purchased my first 1911, a Springfield Armory GI model, and have put a couple of hundred rounds through it with no issues other than a super heavy trigger pull, which I've measured at 10+ pounds with my DIY trigger pull gauge.

After detail stripping it and doing some research it appears that I have an uneven sear/hammer lockup. Looking at the top of the sear, it is evident that probably 80% of the total engagement is happening on only one hammer hook, with only minimal contact on the other hook (only the very inside of the other hook is engaging). Since boosting the hammer won't seem to help this situation (from what I've read), I've come to the conclusion that I either need to adjust the primary surface of the sear to fit, or the hammer flat needs adjustment to get these lined up.

That all being said, what is easier to do? I'm leaning towards the sear surface rather than the flat on the hammer, since this seems easier to adjust. My plan is a sharpie and a ceramic stone, gradually adjusting the sear until I can get a more equal engagement on both hammer hooks.

Comments, concerns, issues?

TIA,

JCR

 

[Jolly Rogers]

I wouldn't work the sear without a jig to maintain the correct primary angle (even though you would be stressing one half of the sear face) I would work the hammer hooks to equalize the contact as I could get close with a vise and a sharpie to monitor the movement.
Joe

 

[1911Tuner]

Could be that the hammer hooks are cut out of square...could be the sear...and it could be that the hammer and/or sear pins are cattywampus. Before you start stoning, find out exactly why the contact is uneven.

 

[WI Birdhunter]

Tuner,

Where can I find specs to determine what's out of spec?

JCR

 

[1911Tuner]

First, you need to determine if the sear and hammer pin holes are correctly located and drilled straight through both sides of the frame. Most critical dimensions are measured from the centerline of the slidestop crosspin hole...either directly or indirectly. The specs are in Kuhnhausen's Shop Manual, Volume 2. If those aren't right, the hammer and sear can be perfect and it won't mean anything.

You can check the sear crown with a toolmaker's square. If the hammer hooks are misaligned, they can be recut, but it requires a mill and an accurate setup to do properly.

A good trigger man can compensate for a little out-of-square/misalignment problem.

Rx

Take it to somebody who knows the 1911's fire control group. That's the fastest, easiest, and probably the cheapest route.

 

[Mac's Precision]

I wouldn't suggest that you attempt to resolve engagement surfaces issues without proper fixtures. It would be difficult for an experienced 'smith to do this let alone someone trying to learn what to cut and where. Unless you have a full understanding of where to cut, how much to cut, and how it is supposed to be once complete...you should steer clear of it and take it to a professional. It will be very hard to maintain hammer hook square and hard to keep the sear surfaces correct and clean. You have a heavy pull now...you might end up with a dangerous situation if your alterations don't go correctly. Please keep in mind that sear alterations affect other parts of the pistol ...not just the trigger pull.

Good luck and stay safe

Cheers
Mac.

 

[1911Tuner]

What he said.

While a sudden full auto event with a 1911 pistol can be exciting, it does tend to frighten the horses and irritate the range officers.

 

[Mac's Precision]

It is rather amazing how fast a 1911 CAN shoot...when sear and hammer angles are wrong!

When I fix guns that come in with complaints of the occasional hammer follow problem....I test fire with no more than 3 in the magazine...should it decide to go full auto.

Cheers
Mac.

 

[1911Tuner]

Yup. I'd guess about 1250-1300 rpms...judging by the old M11 Ingrams of a few years back.

OT, I know...but it's loosely related, so I'll go ahead and tell the story about a friend of mine. I tell this one on him every chance I get.

Honorary cousin and lawman Ken Rainey came to visit from Ole Miss back in June of ought three. Of course, we had to go to the range to ring some steel and do the male bondin' thing while the women stayed behind and talked trash about us. Ken had installed a drop-in trigger job from a well-known/respected shop, and all was well...for about a hundred rounds or so.

He notified me of a hammer followdown. I did the usual checks and nothin' seemed amiss...so I loaded 2 rounds and fired it. It worked fine. It worked fine with 3 rounds...so I topped of the magazine, and tried it again. 7 rounds went downrange in a Mississippi eye blink. The pistol barely climbed off the 12X16 steel plate 10 yards away, with four out of seven bangin' it in rapid succession.

We tried it again, and the gun started doin' 3-shot bursts every time. It was so predictable, that it would do two bursts in a magazine...lock the slide on the last round...and then do 2 shots on the fresh mag. It was uncanny.

Cousin Ken was fairly beside himself, since he'd tossed the original parts away. The gun just kept doin' tri-bursts, and I told Ken that it was way too cool to fix...but he was pretty upset by that time, so I told him I'd fix it

Meanwhile, we had daylight and about 500 rounds to burn, so I loaned him one of my pistols...and then I shot him in the head. Seriously. I shot him in the head. He shrugged it off and finished up the day, and we went back to my place and fixed his Kimber. He finally went to the hospital and got his head tended to about a week after he got home, and he went on to put many bad guys away. Don't let anybody tell ya that them Mississippi law dogs ain't tough.

If he sees this, he'll be along shortly to corroborate. Maybe I'll send him a PM...

 

[Ken Rainey]

Dang, cousin 'Tuner ... you just have to tell how hard headed I am ever chance ya get don't ya ... Yeah, the story is true...'cept the part that I threw the original parts away - heck, I never throw ANY gun parts away! - but, I wanted my NEW NAME BRAND parts to work...and work they did, ... well, after 'Tuner massaged them a little ... Shoulda seen the grin ol 'Tuner had whilst "tri-burstin" that pistol -

Yep, still got the piece of .45 ya shot me with in a pill bottle the Doc put it in after he took it out of my noggin ... shoulda heard me trying to explain that one ...

 

[1911Tuner]

I can hear it now...

"Now, let me get this straight, deputy. You say you were shot in North Carolina...drove back here...waited three days to get it tended to...and you say the guy who did the shootin' is your cousin...and ya still like him?"


I coulda swore you told me that you tossed those parts...

My memory ain't what it used ta be, Kenny.

 

[Ken Rainey]

"My memory ain't what it used ta be, Kenny." hahaaaaa....well, ol friend, mine ain't either .. but, the project with the Kimber was to learn how to work on the 1911 (plus an excuse to come visit the "Tuner) and I kept all the parts that were replaced - yep, still got 'em.

Oh, and I got me another trophy with that Kimber at the Blue Steel Challenge year before last ... 1rst place, as a matter of fact - Thanks again, Cous' !

 

[1911Tuner]

Oh, and I got me another trophy with that Kimber at the Blue Steel Challenge year before last ... 1rst place, as a matter of fact -

In spite of bein' shot in the noggin, too! I tell ya...them Mississippi law dogs is tough!

Anyway...back on topic.

Two important points to be gleaned from this exchange.

One is that drop-in parts may drop in and work...and they may not.

The other is that dinkin' around with the trigger/fire control group in a single-action pistol can bring on some surprises...most of them bad.

To the OP...Find a good trigger man and let him see to the gun.

There's a third lesson.

Cratered steel plates can shoot back.

 

[Mac's Precision]

So I am guessing that a piece of lead or jacket came back from the plates and dug in under your skin?

Aside from that....I am speechless I am not sure I want to go plinking with you guys...if taking a bullet is part of the deal to be buddies.

As for the burst 1911....well...I think it has a market. Certainly on a hi-cap magazine gun.

Cheers
Mac.

 

[351 WINCHESTER]

Well I can't top 1911's story, but I had a colt 1911 that had been accurized by someone who really knew his stuff. I was just a kid, but the gun was scary accurate and never missed a beat - until that fateful day when she ran empty and I inserted a fresh mag and hit the slide release. The slide went down as well as the hammer and I shot my truck and my tire. My ears are still ringing and yes a .45 will penetrate a truck tire up close.

 

[1911Tuner]

So I am guessing that a piece of lead or jacket came back from the plates and dug in under your skin?

Nope. A sizeable chunk of a cast bullet went clear to the bone. It hit him on the bony ridge just behind his eye....the orbital somethin' or another. A half-inch further forward, and he'd have probably lost the eye. A half-inch rearward, and it might have reached his brain. Took him about 10 minutes to get the blood stopped. He was standing a good 10 feet behind me while I shot at a plate about 15 yards away. Rough plates are dangerous. I didn't know just how dangerous until about a year ago when I had nearly a whole cast bullet from a .41 Magnum come straight back at me from 50 yards. It knocked a chunk out of my arm, and would have penetrated if it hadn't hit the bone. It got to me almost as fast as it got to the plate, and it knocked my weak hand off the gun. I'm now a firm believer in not shooting cratered steel...no matter how far away it is.

 

[Ken Rainey]

"I'm now a firm believer in not shooting cratered steel...no matter how far away it is."

So, now I guess it's safe to come back for another visit after all!

In my case, I had a new hammer, sear and disconnect but also a little "nitch" on one leg of the original sear spring that when combined all worked perfectly together to create a tri-burst 1911, well, in 'Tuner's hands anyway, that man has THE touch when it comes to 1911s ... all I could get was hammer follow, sigh ... ... anyway, the 'Tuner generously contributed a sear spring and set it and also fine tuned the disconnect's place in the slide to allow perfect harmony between all parts - she's ran like a champ ever since

 

[Mac's Precision]

Well Ken....

I am glad it all worked out for you. The gun...and your new found lead slug in your temple.

Drop in parts are often not totally "drop in".. In SOME cases you can get away with it...but I find that I doctor most drop in parts in some way. I am very picky about how parts fit...so I rarely buy drop in stuff. I prefer to fit all my stuff as much as possible so I know it is right and fits THAT specific gun.

Most all production guns have such an array of dimensions and tolerances that drop in stuff can be a crapshoot.

Cheers
Mac.

 

[WI Birdhunter]

Thanks for all the advice everyone. One more question for you all - will boosting the hammer tend to even out the sear/hammer engagement?

JCR

 

[1911Tuner]

will boosting the hammer tend to even out the sear/hammer engagement?

Sometimes it will...sometimes not. It depends on how far things have to go in order to equalize the engagement.

One note of caution.

Be very gentle with boosting. Not all hammers are created equal. With MIM small parts becoming the norm, you can destroy the hammer in quick time if you get too enthusiastic. I saw a guy in a gun shop roll the hooks right off the hammer on a new GI Springfield by boosting it for a potential customer. Lucky for him, I had a nearly new hammer that I'd taken off my pistol just a few days earlier. It was a drop-in replacement, and actually gave a little better trigger than the original.

For what it's worth...Boosting isn't an instant trigger job. Althought I've seen it make a feelable difference, all it's intended to do is break the edges and smooth things out a little, and is generally done after a real trigger job in order to seat and burnish the mating parts.

In any event, it shouldn't be done dry. Cock the hammer and dribble a little fine machine oil...sewing machine oil is good...down into the lockwork area and dry-fire a few times to distribute it before boosting. Boost with finger pressure on the hammer...never with a lever.