1911 feeding question

[ATLDave]

What does it mean if a 1911 occassionally (~2% of the time) fails to go into battery because the rim of the cartridge gets in FRONT of the extractor, rather than slipping behind it? Is that an extractor issue, a magazine spring issue, a magazine lip issue?

[rcmodel]

Almost has to be a magazine issue.

Since the bottom edge of the slide is what is supposed to be what pushes the round out of the magazine?
It has to be against the breech face, and slide up behind the extractor.

How else is it getting out ahead of the extractor if it isn't popping out of the feed lips too soon??

rc

[ATLDave]

What if multiple mags of different make generate the same issue?

Would adjustment to COL make a difference?

[tipoc]

Would adjustment to COL make a difference?

Over all length? Are you having problems with handloads?

tipoc

[ATLDave]

Most of the ammo running through the gun is handloads. I wouldn't say I'm having problems with the handloads, per se, that's just the ammo that is available. Since they are handloads, I can change the cartridge overall length if that's indicated by the intermitent FTF.

Since I measure every round at the end of its completion, I know they're all at the published load lengths, and I know they're all within SAAMI spec. I would ordinarily expect them to be able to feed just fine, but if the characteristics of the particular stoppage indicate an ammo issue, I can look at/tweak that, too.

[claiborne]

I had a brand new Dan Wesson PM7 that would not go to full battery (as you desrcibed) at least 2-3 times on each magazine (all flavors of 1911 magazines)
AQfter three trips to the gunsmith and once back to the factory, the pistol still did not function correctly. This was with several types of factory ammo as well as handloads.
I ended up getting rid of the pistol. I hope you can find a solution for your problem. I was into that pistol for about $2500 when I sold it for $800.....boo.

[1911Tuner]

I know that this will hit some resistance. I know it. I also know that it's probably futile...but I'll proceed.

Whenever I've run into an intermittent push feed resulting from jumping the magazine, and I've eliminated the magazine...and more than one can be causing it...almost without exception, the breechface is machined at 90 degrees, or ocasionally a few minutes more, instead of the spec dimension of 89'8" which doesn't include a plus/minus tolerance...which means that the dimension is super critical.

When the problem does stem from the magazine, there are at least one of three conditions present...and often two of the three.

The magazine spring is weak, or...in the case of flush fit 8-round magazines...a couple coils short. Most often, it's both.

The top of the follower is smooth, without the tiny dimple...or "pip" as some call it. That silly little bump was put there a century ago by several very smart men, one of which was a firearms design genius of the first order.

The recoil spring is way yonder too strong, likely installed in the mistaken belief that the frame will be destroyed with the standard spring that those people mentioned in the last paragraph determined was correct for the gun...and that was a 14-pound spring...not 16. Here, the problem is still the magazine. The heavy spring just cast a light on it.

With any feed problem, the magazine is always the first suspect. Always. Start there and work your way back.

[ATLDave]

The fact that my problem is much less frequent makes me optimistic that it's not going to be incurable. And the gun is new, still in a "break-in" period. (Unlike some, I'm willing to accept "break-in" issues, and, frankly, almost never get a gun without one. At least among self-loaders.)

[ATLDave]

Thanks, 'Tuner, I was hoping to hear from you on this! Could you explain a little more about the mechanics/physics of the strong recoil spring causing the cartridge to "jump" the magazine? Is it because its return velocity is so high that it's creating a collision, rather than a push, and the lower-mass cartridge is getting popped ahead of the slide, rather than pushed along by it?

FWIW, the gun came with a stout recoil spring. Maybe the problem will resolve itself as the spring softens up a bit with use. I'm just under 200 rounds into the gun.

[1911Tuner]

Could you explain a little more about the mechanics/physics of the strong recoil spring causing the cartridge to "jump" the magazine?

I'll give it a shot.

First, understand that once the slide starts to move and compress the spring, there's a separate action/reaction system in play with the spring as the vectored force between them. The stronger the spring, the harder it pushes on both.

The upcoming round in the magazine doesn't settle down instantly. It bounces around a bit. When the spring starts to push the frame back, the round obeys Newton 1A and tries to stand still. Then the slide impacts the frame, and tries to jerk the gun out from under the cartridge...so the cartridge winds up further forward in the magazine at the very least.

When the heavy spring accelerated the slide at a higher speed, and it collides with the waiting round, its momentum can knock the round completely loose from the magazine, literally chasing it into the chamber with the nose of the extractor against the case rim.

If the extractor snaps over the rim, you're never the wiser...until your extractor starts to lose tension in a couple thousand rounds...or fails. While a proper extractor is designed to allow a snap over in an emergency, it's not supposed to do it indefinitely.

If the magazine follower doesn't have that little bump on top, the round can get loose when the slide impacts the frame...or it can be barely held by the feed lips, and when the slide collides with it...it's out. If you've ever had a slide locked to the rear with the last round lying loose in the port on top of the magazine...there's your sign.

With a weak mag spring and a heavy recoil spring, sometimes the next to last round will jump the magazine...the last round will bump it out of the port...and the slide will feed the last round. If you've ever found live rounds among your brass...heeeeere's your sign.

That little dimple and the correct springs are important.

[Fishslayer]

Originally Posted by 1911Tuner

That little dimple and the correct springs are important.

Have you been talking to Ruger? Their SR1911 magazines come with the dimpled follower.

I've become a fanboi for the Checkmate 7 rounders with dimples. I don't think there's a better magazine for $18-ish. Wonder if they make the mags for Ruger.

[handyman163]

I've only had this happen once, and on the same range trip, I had a couple of those malfunctions where the round ended up in front of the extractor. I was also shooting my reloads. I changed ONE thing, and it's been cured forever - clean the magazines. Strip them down and clean out the inside. The bullet lube from my lead SWC reloads had gummed up the mag so that the follower was sluggish, and wasn't popping the rounds up properly - unnoticeable when loading/unloading or otherwise looking at the mag, but they were dirty inside. I had people telling me extractor issues, you name it. That's all I did, and kept them clean since and it never has happened again. You may try that, though I'm far from an expert.

And to Fishslayer:
Checkmate does make the Ruger magazines. They have the checkmate follower and hybrid feedlips.
You can get them at TopGun Supply when they're in stock, which of course they are not.

http://www.topgunsupply.com/check-ma...-magazine.html

http://www.topgunsupply.com/check-ma...-magazine.html

[tuj]

That little dimple and the correct springs are important.

I don't doubt you, but I have been using Tripp mags with hybrid followers that do not have the dimple and I've never had a mag-related malfunction. Maybe the design of the feed lips on the Tripp Cobramags is a little different?

[1911Tuner]

Maybe the design of the feed lips on the Tripp Cobramags is a little different?

Got more to do with that gorilla spring Virgil uses in'em.

[Ramone]

Originally Posted by 1911Tuner

Got more to do with that gorilla spring Virgil uses in'em.

I was just about to ask about that- I had a mag that would sometimes feed the round in front of the extractor (and it did have the dimple, as I recall), and a new spring solved it.

[Fishslayer]

Originally Posted by handyman163

Checkmate does make the Ruger magazines. They have the checkmate follower and hybrid feedlips.
You can get them at TopGun Supply when they're in stock, which of course they are not.

That's exactly where I got mine. Should be good for awhile. Got 2 of the blue 7rd and 3 of the SS 8rd. The Ruger comes with one of each. The 7rd spring is noticably more robust than the 8rd.

[1911Tuner]

I had a mag that would sometimes feed the round in front of the extractor (and it did have the dimple, as I recall), and a new spring solved it.

The main player is the spring. The dimple...an example of Browning's penchant for redundancy...is a backup in case the spring's tension is less than optimum. It's not a guarantee, but rather a little added insurance. Of course, having the dimple correctly located and within spec dimensionally is also a requirement, and the 1911 is at its best with a magazine that releases the round gradually and late as opposed to many modern magazines that release it too early and too abruptly.

[Jolly Rogers]

Got any thing to say about slippery plastic followers some mag builders use??
Mostly on those early abrupt release mags?
Joe

[1911Tuner]

Well, mama always told me that if I ain't got anything good to say...

Seriously, though, enough spring covers a multitude of sins. Tripp demonstrated that in the Cobra...which incidentally...also uses an extended tube and a full-length spring, as does Check Mate's redesigned 8-round unit with their patented "Bullnose" follower, which is little more than a Devel folded follower with a skirt and a dimple. When I was corresponding with them during the development on that one, I had a helluva time convincing them to use a dimple and enough spring. When they finally saw the light, their 8-round magazines became much more reliable.

[Krogen]

Thanks to you, 1911Tuner. You oughta' write a book! I'd buy one.

[1858]

Originally Posted by ATLDave

What does it mean if a 1911 occassionally (~2% of the time) fails to go into battery because the rim of the cartridge gets in FRONT of the extractor, rather than slipping behind it? Is that an extractor issue, a magazine spring issue, a magazine lip issue?

So given 1911Tuner's responses, I'd like to know if you typically experience this issue with the last round or second to last round. You mentioned that the problem occurs with more than one magazine but don't mention when the problem occurs.

[Rubber_Duck]

I am just fascinated by all the naunces of the 1911's operation and I've learned even more about what goes on in a 1911 by reading this thread. Thanks for the informative and easy-to-understand answers!

Carry on.

[Skylerbone]

Might be nice to know what brand 1911 we're talking about as well as there are several known for issues with the breech face, among them the old (and possibly new???) Auto Ordnance and S&W, though they don't hold exclusive patent on machining errors. Any pictures of the brass?

[il.bill]

Originally Posted by 1911Tuner

The dimple...an example of Browning's penchant for redundancy...is a backup in case the spring's tension is less than optimum. It's not a guarantee, but rather a little added insurance. Of course, having the dimple correctly located and within spec dimensionally is also a requirement

I purchased several 'Colt' branded magazines from Robertson's expecting to see dimpled followers, but it was not the case. I read one time 'there is no such thing as a dumb queation', but I realize a dumb guy like me can still ask a question, so here goes: Can a properly located to specs dimple be added to the follower carefully using a center punch struck from the bottom?

[1911Tuner]

I purchased several 'Colt' branded magazines from Robertson's expecting to see dimpled followers, but it was not the case.

You probably ordered 8-round Colt magazines, which are nothing more than Shooting Stars with Colt's pony on the baseplates. A picture will tell more of the story.

Can a properly located to specs dimple be added to the follower carefully using a center punch struck from the bottom?

No. It's a punch and die operation.

Here's a picture comparing the three basic feed lip designs.

On the left is the original "Hardball" type with full tapered feed lips and late, gradual release.

On the right is the "Wadcutter" type, with parallel lips and early/abrupt timed release.

In the middle is the "Hybrid" which combines the feed/release characteristics of the other two.