Sear Failure


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1911Tuner
July 16, 2004, 08:53 AM
Mornin' ladies and gents. I saw my first (Colt) catastrophic MIM sear failure
today.

I got up early to make coffee and get the dogs out for their A.M run, and
went to my truck to fetch a pack of Camels that I'd left in it. Door was
locked...which isn't my habit. I saw a Colt pistol box on the floorboard with a note taped on it. Note said..."Check it out. Trigger feels weird and the
hammer falls to half-cock on every other shot. Be back at noon."

Well...That explains why the Labs went nuts around 3 this mornin'.
Good dogs! :cool:

Okay...Hmmmm. I cleared the gun, cocked it and pulled the trigger.
Rough, rollout break...not too light, but not exactly right for a stock Colt.

Poured a cuppa turbocoffee and started breakin' it down. As I lifted the
sear spring out, I saw a sliver of metal. It was the sear crown...about
.050 inch of it at the narrow end, and probably a 64th wider on the other. The gun is a mid-90s production LW Commander that's probably got
5-6 thousand rounds under its belt. Not heavy use, but not pampered
either. He bought the gun from me 4 years ago to carry off-duty.

I had a lightly used Colt MIM sear that I took out of that stainless XSE
when I upgraded it. It dropped in and worked with very little massaging,
which speaks well of Colt's parts interchangeability...The trigger pull is
about where it was with the old sear, and firing 10 rounds in two-shot groups didn't indicate that there was a problem. Don't know if he'll be okay with another one just like the other one...I'll advise that he let me refit
the gun with a steel sear and disconnect. If he blows it off, I'll call his wife and get her on his case.

COLT!!! ARE YOU READING THIS?

Luck!

Tuner

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Cherokee180
July 16, 2004, 09:20 AM
Tuner,
Darn MIM!
Oh well--at least this sear failure didn't cause an AD. That JMB design is amazing.
Thanks for the report.
Doug

Old Fuff
July 16, 2004, 10:41 AM
>> He bought the gun from me 4 years ago to carry off-duty. <<

Sure is nice that it broke at the "right time," rather then under less fortunate circumstances. I noticed that this LW Commander has been around for 10 years, with moderate use. Contrary to what some believe, MIM failures do not necessarily happen early in the pistols life, nor after a few hundred rounds.

Do put in a "real steel" sear, and maybe some other parts. This gun's owner may have to defend his life.

I sure wish the folks in Hartford gave a hoot ....

Wildalaska
July 16, 2004, 11:20 AM
I sure wish the folks in Hartford gave a hoot ....

Agreeing with the general proposition that the only good MIM is no MIM, I have yet to see or hear of a sear breaking, under even severe use, on any Colt pistol we have sold (or even see), and we sell a lot.


WildanythingcanbreakAlaska

Old Fuff
July 16, 2004, 11:51 AM
Wild-AK:

I don’t mean to pick on Colt. When it comes to MIM parts they have plenty of company. But it used to be that the major U.S. handgun makers were acutely aware that many of their customers literally staked their lives on the company’s product, and they accepted the responsibility of doing everything possible to insure that a handgun with their name on it wouldn’t fail at a critical time.

Yes, they sometimes did some cost cutting (after World War Two Colt .45 triggers were no longer made from one piece of steel) but they didn’t worry about saving a few pennies by compromising critical parts.

Today that completely turned around. Pennies are more important then lives. I’m not looking to see wholesale failures of Colt (or anyone else’s) MIM sears. My point is that it only takes one to cost a life, and because of the methods used in its construction, failures through thin cross-sections are predictable.

I am saddened sometimes by the realization that American law enforcement officers are far more likely to be carrying a European company’s pistol (Glock, SIG, H&K or Berettta) then one with a traditional domestic manufacturer’s name on it. In a sense, I am part of this industry, and I think something is deeply wrong.

wally
July 16, 2004, 12:39 PM
MIM failures do not necessarily happen early in the pistols life, nor after a few hundred rounds.

Neither do failures in forged/machined parts! Extractor on my Series 70 Colt broke after 5000+ rounds whiel I was shooting my CHL qualifier.

--wally.

P95Carry
July 16, 2004, 01:25 PM
I am not a MIM fan - on principle ..... just the metallurgy aspect ..... however - any part can fail, almost at any time. Murphy can ensure that.

Makes a BUG seem ever more useful .... plus (not knocking semi's) - the good ol' revo will not quite so easily go belly up with a critical failure.

I do feel that a carry piece should ideally, be well broken in but - not ''punished'' with vast throughput of rounds ..... practice is necessary, of course but IMO better done with a dupe gun that is asigned practice duty only, and not carry - where the reliability factor is so crucial.

Thx for the report on that Johnny ....

R.H. Lee
July 16, 2004, 01:40 PM
Anything mechanical can and will fail. There is no reason to increase that likelihood. This is a good reminder to identify and swap out MIM for machined/forged parts-and then start testing all over again-as if it were a new pistol.

Thanks.

1911Tuner
July 16, 2004, 02:11 PM
Wally said:

Extractor on my Series 70 Colt broke after 5000+ rounds whiel I was shooting my CHL qualifier.

Was it barstock or cast? I haven't seen one, but I've heard from three sources that there were cast extractors in some of the S70 Colts.
After numerous failures, Colt returned to barstock extractors....in much
the same way as they've done recently with MIM puller-outers.
Fuff may have personal knowledge of these "mystery extractors" in
the Colts.

I've seen machined steel extractors break too...even Bulletproof and
Hardcore parts...and the breakage repeated on the replacement parts.
Examination revealed that other factors were involved...the most-often
noted cause was a feeding problem, with the pistols push-feeding and forcing the extractors over the rims. A few showed evidence of contact
between the front of the extractor and the barrel. Some pistols showed
that the cause was unlock/linkdown timing of the barrels were breaking things. The extractor in the 1911 or any other design was never intended to pull a case out of the chamber while pressures were at or near maximum.

There are several issues that will cause early extractor failure, other than shoody materials. The pistol has to be operating properly too. There
are many 1911s that are timed just so, and will function surprsingly well without an extractor even being in the gun, given true hardball-spec ammo.
There are other s that won't...and there are still others that, by the virtue of their cycle timing and/or owner's insistence on using ammunition that the
gun was never intended to function with...will place stresses on the extractor that it was never designed to accomodate.

Cheers!

Tuner

1911Tuner
July 16, 2004, 02:24 PM
WildridetheponyorbesquareAlaska said:

I have yet to see or hear of a sear breaking, under even severe use, on any Colt pistol we have sold (or even see), and we sell a lot.

This was my first Colt MIM sear breakage, too. The point is not to bash Colt. In the FWIW category, neither Colt nor Springfield make their own sears any more. The get them from outside vendors, and are completely
dependent on the quality control efforts of those vendors. As the contract
bidding wars become more vicious, we can probably expect to see more
instances of small parts failure in the 1911 and other designs...no matter
whose logo is on the guns. Why? To save a dime per part, as per the
corporate bean counters' dictum.

Be sure not to miss my response directly above. It's worth reading
and well worth considering.

Cheers!

Tuner

Old Fuff
July 16, 2004, 02:57 PM
I too have seen "real steel" extractors break. In particular, USGI steel cased hardball, intended to be used in sub-machine guns, could and would do a number because of the case's narrow rim/extractor groove.

I, like Tuner, have also seen extractors break because of various issues due to mis-fitting. And in one case I came across a Colt extractor (material unknown) where the camming bevel on the bottom of the hook was never made (!!). Did Colt experiment with investment cast extractors? I understand they did, although I don't have details. This sort of thing remains unspoken, unless it works.

So far as MIM extractors are concerned, I am more worried that they'll lose tension over time rather then break, but breakage is a concern in certain areas.

Tuner's recent testing of a S.A. should have made it clear that even an experienced 'smith can't make a MIM extractor work for for long, and that replacement is the only good answer.

1911Tuner
July 16, 2004, 03:29 PM
Old Fuff said:

USGI steel cased hardball, intended to be used in sub-machine guns, could and would do a number because of the case's narrow rim/extractor groove.
_____________________

The front of the extractor hook making hard contact with the forward part of the extractor groove would pop one pretty quick. I've seen it happen
even with commercial ammo when the extractor's dimensions were out of spec, and allowed contact there. The telltale sign is a dent in the case extractor groove's forward angle. Other causes not related to the extractor's dimensions will also allow that contact...incorrect headspacing
being one of them.

The gun has to be built to spec in all areas in order to live long and prosper.
The tolerances and dimensions on an ordnance-spec pistol AIN'T that hard to hold, especially with CNC machinery.

Fuff...The Springfield extractor *appeared* to be barstock...but it was
either substandard steel or piss-poor heat treatment that caused it to
lose tension as quickly as it did...plus the fact that it was dimensionally out of spec for a .45 extractor. (Too narrow on the hook) Springfield has had
ongoing extractor issues for 2 years. Seems that somebody in Geneseco
would have taken notice by now...or maybe they just don't care.

Cheers!

Tuner

carpettbaggerr
July 17, 2004, 01:40 AM
How come the 1911 fairy never visits me? I left .45 casings under the floormats, but they're still there. :(

Texas Bob
July 17, 2004, 08:20 AM
1911 Tuner and Old Fluff, how are the "parts used" in an Ed Brown Kobra compare to what they should or shouldn't be. I bought a used Kobra off another member, should be in my hands next week. I haven't owned a .45 in almost 25yrs. and I needed one to complete my battery.

1911Tuner
July 17, 2004, 09:45 AM
Howdy Bob,

I really can't say, since I've never opened up a Kobra, and only seen one.
Nice pistol, by the way.

Ed Brown offers two identical Hardcore hammers...One is machined barstock, and the other is cast. Be sure to read the fine print. I
would be willing to bet that the Kobra has the machined hammer.

Never used a Brown sear. I've always used the Nowlin Pro-Match.
Nowlin also offers two sears. One is machined steel and the other
"Factory Enhanced" part is MIM.

I've always used Briley machined disconects...so I can't offer an
opinion on Brown's, one way or another.

Brown's slidestops are castings, but seem to be very good ones. The
Hardcore extractor is steel, and also very good. Correctly prepped and fitted, they'll hold tension and last for years. I've got one that's seen
something over 20,000 rounds in two different pistols before
testing it for just over a year by keeping a dummy round continuously
chambered...pulling the slide back just enough to check tension and returning it to battery. Tension is still as it should be.

'Bout all I can tell ya...

Luck!

Tuner

dubb-1
July 17, 2004, 10:59 AM
Thanks for the heads up!

MMMM, turbocoffee!!!

1911Tuner
July 17, 2004, 11:35 AM
Howdy Dubb! Welcome in.

Coffee's ready, mah fren. Git some!

Wildalaska
July 17, 2004, 01:46 PM
Gonna put a plug in for the C&S parts...and Bill Laugfhridge is a gentleman on top of it...

WildourpersonalpistolshaveC&SpartsAlaska

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