Colt GM

[Tom W.]

My Colt GM is giving me fits. After 4 or 5 shots the firing pin stop dislodges and locks up the pistol. Now, before anyone howls, I bought the pistol new in the mid '70's and have yet to replace anything but some new magazines and an extended slide stop safety.
My guess is that I need either /or/ and/ a new firing pin spring and firing pin stop.
Any other guesses?

[Boogieman]

If you haven't changed the recoil spring it's past due. A worn spring allows the slide to travel too fast & can jar the firing pin stop loose. If you order a new Wolf recoil spring it comes with a new firing pin spring. Brownells lists them for $7.95. If that don't fix it I'd replace the stop.

[Mk42gunner]

Yep, two new springs and you should be set for anther thirty or forty years. Might not be a bad idea to take a look at the firing pin also, while you are in there.

Robert

[Tom W.]

Well, I ordered the 2 springs and stop from Colt, should be here by the middle of next week, I hope.

I suspect I was a bit overdue...

[Tom W.]

Got the parts in and still had an issue w/the firing pin stop. It did drop down one more time. I somehow managed to ruin a magazine while at the range, and didn't take another one with me, so the gun didn't do as well as it should have. Maybe I'll go again Monday night...

OTOH, both of my Glocks did wonderfully.... Still shooting J bullets until I can get near a press.....

[seagiant]

Hi,
In my humble opinion you might need to obtain an "oversize" firing pin stop from EGW. They are available from Brownells or Midway. You will also need a #2 pillar file to fit. Not that hard to do really,but is a permanent fix! http://www.midwayusa.com/product/783...series-70-blue

[Boogieman]

If your FP stop is not a snug fit oversize stops are aviabile & are not hard to fit. An extra power FPS will help keep it in place.

[reed1911]

May I make a suggestion and remove both the stop and spring and use a rod to push the FP into the channel and see if it travels freely. This issue I have seen before and the cause was a burr on the FP once, and several times a piece a primer material in the channel. Hung the FP just enough to prevent enough tension on the FP to hold the stop in place. Could be gummed up too. I only bring it up since the new stop and spring did not correct the issue.

[seagiant]

May I make a suggestion and remove both the stop and spring and use a rod to push the FP into the channel and see if it travels freely. This issue I have seen before and the cause was a burr on the FP once, and several times a piece a primer material in the channel. Hung the FP just enough to prevent enough tension on the FP to hold the stop in place. Could be gummed up too. I only bring it up since the new stop and spring did not correct the issue.

Hi.
Very good idea,but I had ASSUMED that a good cleaning had already been done! I think you can ask any working gunsmith and he will tell you a GOOD cleaning fixes a lot of problems with all firearms!

[MtGun44]

If the firing pin is moving freely in a clean channel, I would fit an oversized stop.

One other idea comes to mind.

How is the extractor tension? The extractor should take a firm push to seat it into
the slide, say 10 or so lbs thumb push. A low or zero tension extractor may be
contributing to this issue.

Bill

[reed1911]

If the firing pin is moving freely in a clean channel, I would fit an oversized stop.

One other idea comes to mind.

How is the extractor tension? The extractor should take a firm push to seat it into
the slide, say 10 or so lbs thumb push. A low or zero tension extractor may be
contributing to this issue.

Bill

I'm not questioning your answer in terms of validity, but please explain as I don't understand why this would add to the issue?

[ultramag]

If the firing pin is moving freely in a clean channel, I would fit an oversized stop.

One other idea comes to mind.


I'm not questioning your answer in terms of validity, but please explain as I don't understand why this would add to the issue?

Because the FPS and the extractor are, or should be, fit together for everything to be lined up and tensioned properly. The two work together and are somewhat dependent on each other.

[reed1911]

hmm..okay I see what you mean. I have never seen that cause an issue, however I certainly have not seen it all by any stretch. A good thing to keep in mind. Just another tip of the trade to stash away in my empty head. Good on you Ultramag.

[Boogieman]

A bent firing pin could cause this problem Also IF this is a series 80 Colt the firing pin blocking pin could be sticking. Check for dings or burrs ,a weak springs or crud in the hole.

[seagiant]

Hi,
To be honest all of us here are taking only a "shot in the dark" on this as we really have no real info to go on! Most are assuming because it is a "COLT" pistol that all the parts are in "spec"! That would be a mistake as COLT has problems like anyone else!

All 1911"s should be looked at as individuals though of the same family. A whole industry has sprung up to make accurate or "oversize" parts to take care of pistols with out of spec slides and frames! This also includes the top manufacturers!

Just sayin 1911s are not a plug and play pistol and any shooter would be advised to spend a little on education to enjoy them even more!

[MtGun44]

On a 1911 the extractor hole goes through the firing pin stop groove, and the two parts
intersect. The FP stop retains the extractor, and they can interact. If the extractor is
flopping around loose in it's tunnel, it may have some (abnormal) interaction with the
FP stop. Definitely not a normal situation for the FP to pop loose, it is a failure that I
have never personally observed in any 1911. I have shot and watched literally many
millions of rounds fired in 1911s over the last 35 years, and until now, I thought I had
pretty much seen all of the kinds of failures that the design was prone to.

Since this is such a rare malfunction, it seems prudent to be extremely thorough and
to examine the proper fit and function of ALLof the parts that share that
particular space and interact with each other at all - no matter how unlikely it seems.
Just a good troubleshooting method - look at everything that touches the problem part
and maybe you will find something out of spec - or more likely, several things together
that are out of specification and each bringing their own piece of the problem "to the
party".

Bill

[Boogieman]

The OP said this gun had been working fine since the mid 70's. Something is worn, bent. or broken. The FP stop can't come out with the FP at rest. Some thing is holding it forward allowing the stop to drop down. Anything slowing the firing pin could cause it.

[Tom W.]

Yup, It's a Colt Series 70 bought new, and everything is clean. I can't tell you how many rounds have been through it, but it's been a whole lot, I can assure you. I'm going to pull the stop out and re-inspect the firing pin. But I don't have any troubles with the pistol going "boom" either with handloads or factory loads. It's got me scratching my bald head....

Boogie man, the FP stop only fell down, not completely out, after a round was fired, while the slide was in motion. I'll take it back to the range shortly and see what transpires later this week.

[Boogieman]

I would look very hard at the firing pin for a bow or burr ,not a rare thing with a gun that's been fired alot. Also the tip of the pin can mushroom slightly, slowing it's return, binding in the breech face.

[jmsj]

Tom,
I have run into this once before. It was on a Bullseye competitor's 1911. We have no idea on the round count but I believe it to be high. This gun has also has seen a lot of dry fire practice. The owner said the gun was still scoring very well but this was a big issue. I looked at the firing pin and it measured out O.K. and the firing pin tunnel looked good as well. Being that he was on his way to a shoot and I did not have the correct series 80 firing pin stop in the shop and would not be able to get one in time, I was able to use center punch and raise a little metal to keep the stop in place even without the firing pin or firing pin spring. I also put a new E.P. firing pin spring in and the gun worked just as it should. This was not the correct way to fix the issue but it did allow him to compete that weekend and not have a problem. I ordered a new oversized stop and installed it the next week for him. I see him all the time and he has never mentioned having any issues with the firing pin stop coming loose gain.
Good luck, jmsj