Colt S80 malfunctions

[showpro]

My Colt S80 is very accurate, but when it gets to the last round in the mag, the slide locks back prematurely. Usually, the last round is freely rattling around in the open action. Sometimes, the second to last round fails to feed into battery.

I swapped out the slide stop, same symptoms. I've tried 6 different mags in 4 different manufacturers.

Any ideas here?

The only thing I can see wrong is there's a sort of blemish, like a gouge, inside the slide on the center rail about half way between the breech face and the rear of the slide. Could that catch the rim of the last round as the 2nd to last round is being fed into the chamber?

I'm at a loss, here.

[wichaka]

Whats mags are you using?

Sounds like the mag springs are weak.......might get them replaced. When a mag gets to the last round, the spring is at its weakest point, as there's no tension on it.......or very little.

So it can't control the last 1-2 rounds very well.

[showpro]

Brand new Wilson 47Ds.
Brand new Colt factory mags.
Brand new Kimber factory mags.
Older Colt factory mags that work fine in my S70.

In fact, all these mags work fine in my S70 Gold Cup.

[wichaka]

Check the tension on the extractor, as it should control feed the rounds out of the mags.

The slide stop could have a mis-shaped lug, where it contacts the mag follower early, keeping the follower somewhat depressed allowing the rounds to come free.

Hmmmm will need pics of the slide stop lug, and also the position the round is in when it fails.......would help.

[showpro]

Well, I've tried 2 different slide stops with the same result.

The position of the round varies. Sometimes it flies out of the action onto the floor. Sometimes it's just sitting in the open action, on top of the mag, but not in the mag. Sometimes I get a 3 point jam on the 2nd to last round. Sometimes the 2nd to last round is in the chamber, but out of battery.

In the latter 2 cases, if I drop the mag, the last round in the mag is pushed forward about 1/2 an inch. Don't know if that's normal, or not. In fact, as I recall, if I remove the mag at any time, the top round is pushed forward.

I appreciate the attention, wichaka.

[John]

Weak magazine springs is the obvious answer. When the one before the last jams, pull and lock the slide back and check the position of the last round. If it is not fully seated in the magazine, all the way back, then your mag springs are not OK. Also, what recoil spring do you have in this gun?

[showpro]

Weak magazine springs is the obvious answer. When the one before the last jams, pull and lock the slide back and check the position of the last round. If it is not fully seated in the magazine, all the way back, then your mag springs are not OK. Also, what recoil spring do you have in this gun?

The recoil spring is whatever Colt put in it at the factory. The gun is new and has only 200 rounds fired.

The magazines are also brand new. Why would Wilson mag springs be weak when brand new? Is this a known issue?

[1911Tuner]

When it gets to the last round in the mag, the slide locks back prematurely. Usually, the last round is freely rattling around in the open action.

That little trick is known as "Jumping the Follower" and it's a magazine problem. More likely to occur in magazines without a positive means to the last round under recoil inertia...the spring tension is also a player. A stronger spring will help, but may not completely eliminate it. Most often happens on the last round, but sometimes
causes the next-to-last round to eject from the port while the gun feeds the last round.

The recoil spring can also contribute to the problem. Too strong or too weak...Either one can and does have an effect. Since most folks tend to overspring...if you've replaced the recoil spring...this may be part of the cause.

[showpro]

I appreciate all the help, guys.

So, again:

Brand new Colt. 200 rounds, factory springs and everything. I haven't replaced at thing.
Brand new Colt mags that came with the gun. Again, no mods.
Brand new Wilson 47D mags. Haven't changed a thing.
Also tried older Colt mags and brand new mags that came with a Kimber.

So...I find it hard to believe that these springs need to be replaced in all five of my brand new mags. Or that the mag design is bad from Wilson or Colt out of the box. Are these known to be bad mags?

Could Colt have put the wrong recoil spring in the gun? I could replace it...I have a spare.

This is all hardball ammo, btw. Could the nose of the ammo be pushing up the slide catch? Maybe needs the slide catch to be "dimpled"?

[1911Tuner]

So...I find it hard to believe that these springs need to be replaced in all five of my brand new mags.

Well...Okay. :)

But...Just in case your belief system is open to suggestions...Here's a mechanical description of what you gun is doing.

Luck!

http://forum.m1911.org/showthread.php?t=1959&highlight=Inertia%21

[showpro]

Well, my belief system is certainly open, and I truly appreciate all the feedback.

The piece you pointed to is interesting and educational. But I'm not getting what you're proposing I do here.

Keep trying different brand of mags until I find one that works? That gets expensive. Why don't the Colt mags just work out of the box? They're 7 round and have the dimple, right? So were the Kimbers, IIRC.

Replace my brand new springs with other brand new springs? Why?

The theory is great, but I don't see how it logically points to a remedy...

[wichaka]

Not sure where you're at, but if you're close to WA State, drop in and we'll look 'er over for ya.........no charge.

[showpro]

I'm in Bellevue, WA. That's a nice offer. How far are you from Seattle?

[wichaka]

Actually I'll be up in Seattle this next M-W...........PM me your contact ifo, and let's get together and I'll look it over.

I'm down along the gorge..........east of Vancouver..........near Mt. Adams. Check out my web site on my sig line, that'll give you all the details.

[1911Tuner]

Keep trying different brand of mags until I find one that works? That gets expensive. Why don't the Colt mags just work out of the box? They're 7 round and have the dimple, right? So were the Kimbers, IIRC.

Replace my brand new springs with other brand new springs? Why?

New doesn't guarantee good. 98% of your problem is with the magazines. Most feed-related problems are the fault of the magazine. You'll hafta trust me on this one...

First, a question:

Are you using a shock buffer in the gun? If you are...take it out and see if anything changes. Some guns run fine with'em, and others choke like a pukin' buzzard...and nobody seems to know why except the gun.

It's a system that requires enough mag spring along with the dimple, and the recoil spring also figures in. Too soft or too heavy, and you can get exactly the sort of malfunctions that you're describing. Colt's OEM recoil springs tend to be a little light.
Check the bottoms of your Colt 7-round magazines. If there's an "M" stamped on it, it's a Metalform. Good mags, but their springs could be a lot better. Ditto for Okay (O)Industries. Check-Mate's springs have historically been good to go.

McCormick Shooting Stars have soft springs. Powermags have much better springs, but the Devel follower is the chink in their armor. Wilson 47Ds have weak springs.
You can turn a SS into a Powermag with a Wolff +5% spring.

On the premature slidelock issue...you've probably got a bullet nose nudging the slidestop lug. With the slide off/slidestop in...use a strong light as you push the magazine up into the well to see where the contact is, and dress the stop lug to provide a little clearance.

If that's not it, install a new Colt plunger assembly. Available from Brownells for about 5 bucks.

[wichaka]

When I go check his gun out Tuner.........I'll take some of my trusted GI mags, along with some tools.........we'll get R done.

[1911Tuner]

I'll take some of my trusted GI mags, along with some tools.........we'll get R done.

If you've got an 11-pound Wolff spring layin' around, stick it in the factory 7-rounder.

[twin oaks]

Tuner, after reading your link ( about inertia) I can only think that the newer designs of the magazines allow for some more better things. By leaving out the dimple on the follower the mags are easier to load. By making them 8 rounders, the companies are just trying to ensure that the shooter can still get 7 reliable rounds even with the FTRB! Now we've got the best of both worlds: easy to load AND fire 7 rounds.

I have to agree with your post on this too: " If 7rds of .45 doesn't solve it, I'm in over my head", so . . .I carry two spares. now if 22 rounds won't cure it, I should've been running away long before the 1st round.

Showpro, LISTEN to Tuner, he's forgotten more about 1911's than most of us have learned.

[1911Tuner]

your link ( about inertia) I can only think that the newer designs of the magazines allow for some more better things. By leaving out the dimple on the follower the mags are easier to load. By making them 8 rounders, the companies are just trying to ensure that the shooter can still get 7 reliable rounds even with the FTRB! Now we've got the best of both worlds: easy to load AND fire 7 rounds.

Might wanna rethink that. Without positive control of that critical last round, you also get a high chance of a push-feed, with a resulting sxtractor snapover...which is hard on extractors. Tension goes away...or they break. Failures to feed and return to battery are much faster to clear. A failure to extract is a malfunction that you don't want even once.

John Browning put that silly little dimple there for some very good reasons, and...since it's an extra operation in the manufacturing process that takes time and added tooling expenses...if it weren't necessary, it would have been eliminated almost a hundred years ago.

Browning really did know what he was doing...

[showpro]

I'm pretty sure twin oaks was joking. Probably should have put a winky in there.

[1911Tuner]

I'm pretty sure twin oaks was joking.


It is furiously to hope... :)