Troubleshoot Thursday: Another Springfield

[John Travis]

Late 90s production Springfield Champion. Intermittent failure to go to or return to battery. most often on the top two rounds but can occur at any place in the magazine. Slide stopped about a quarter inch out of battery. Slide could sometimes be pushed into battery, but usually not.

Feed and barrel ramp were within spec and hadn't been wrecked by Dremel Dan.

Chamber was smooth. Headspace was good. Owner performed plunk test with different bullet types and saw no issues.

Extractor tension was actually a little light due to owner backing off on it to try to get the pistol to run. Claw to wall dimension was .034 inch.

All springs were OEM.

The magazine(s) was/were not causing the problem.

The problem was visible. The fix took about 15 minutes including teardown and reassembly. Pistol reportedly ran through 10 magazines without a hitch. I do love happy endings.

Most recently...starting around the early 90s to present...this is most often the cause of failure to go to/return to battery problems I've seen. I rarely saw it up to that point.

I'll be back early in the AM.

'Night all. 0400 comes early at Castle Doghair.

 

[MacEntyre]

Halfway through reading this, Grasshopper says, "It's the magazine!" and then reads that the mags didn't cause this problem.

Therefore, it's excessive extractor deflection.

 

[John Travis]

Halfway through reading this, Grasshopper says, "It's the magazine!" and then reads that the mags didn't cause this problem.

Therefore, it's excessive extractor deflection.

You have learned well, Grasshopper. By your assuming that it was the magazine, you also demonstrated the usual first assumption that most people make. Contrary to popular belief, the magazine is not the cause of 90% of all feed problems. It's the extractor.

This is a problem that I rarely saw in earlier pistols. Even the trash cast extractors found in the Thompson Auto Ordnance abominations had proper deflection. I don't know what happened 25 years ago, but it seems like nobody even considers it any more. I've even seen it in high end custom and semi-customs.

It's the single biggest cause of ruined feed ramps and cries of "junk magazines" in the industry as the first response to such a misfeed is to scrap the magazine and/or polish the feed ramp.

Most of the time, the problem stems from the extractor's dimensions. Either the front pad allows the extractor to sit too close to the breechface centerline, or sometimes it's too much meat in the tensioning wall, and...even worse...sometimes the extractor channel location itself is to blame.


And worst of all, if the channel is angled front to rear, the butt end of the extractor is too far from the firing pin stop to keep it from clocking along with excessive deflection that clocks it...and there is no quick cure. The slide must be replaced.

With the proper deflection...the right amount of tensioning wall in the breech area...the pistol will feed so smoothly that you can scarcely tell that it chambers a round when the slidestop is tripped on a fresh magazine. With the correct deflection, you can run more extractor tension than is widely accepted as the "right" amount without issue. With the correct deflection, there's no need to bevel or radius the bottom of the wall, which can be detrimental itself if over done. When it's right, lightly breaking the corner at 45 degrees is all that's needed. Lightly. With the proper deflection, most pistols will feed and go to battery even with junk gun show magazines.

I like to see about .010=.012 inch of the wall protruding past the guide block and .015 is the maximum. (It depends on the distance between the blocks. On that dimension, I like to see .484-.486 inch.) More than that makes tensioning a little tedious. When it gets close to .020 inch, you're at the point of having to cut a bevel into the bottom of the wall. Much beyond that, and you've got a pistol that consistently fails to go to battery no matter what you do to "tune" the extractor by bending and straightening it and increasing that bevel.

I've had them show up with .030 inch or more. The pistols were failing at least once on every magazine...sometimes pistols that had been back to the manufacturer without resolving the problem.

In most instances, the cure was cutting material out of the tensioning wall with a safe-sided rail file and adjusting the claw to wall length as outlined in the previous troubleshooting thread. That worked on this Champion, and the pistol that couldn't get through a magazine without a hangup suddenly started behaving.

If memory serves me, I made such an adjustment for one of the forum members a few years back. Can't remember who it was. Maybe if he sees this, he'll chime in.

I've got one more Troubleshoot topic. I'll do it a little later today.

Stay tuned! (Pun intended)

 

[MacEntyre]

And worst of all, if the channel is angled front to rear, the butt end of the extractor is too far from the firing pin stop to keep it from clocking along with excessive deflection that clocks it...and there is no quick cure.

Two questions about clocking extractors...

If the channel is correct, and the extractor is correct, then the extractor cannot clock because the the firing pin stop fits tight in the notch in the rear of the etractor.

Q1: when there is excessive deflection... too much tensioning wall in the breech area... does that tend to move the notch away from the firing pin stop, allowing it to clock?
In other words, front end goes left, so rear end goes right...?

Q2: what else causes extractor clocking?

 

[John Travis]

If the channel is correct, and the extractor is correct, then the extractor cannot clock because the the firing pin stop fits tight in the notch in the rear of the extractor.

In an ordnance spec pistol, the stop isn't really a tight or close fit to the extractor slot. It can actually be fairly loose. In such pistols, the extractor can rotate...or clock...a little, but usually doesn't unless there's also excessive deflection. As long as the rotation isn't excessive, it doesn't cause a problem. Only when it can turn far enough counter clockwise for the tensioning wall to lose contact with the case rim. Or viewed from the back of the pistol, the tensioning wall and case rim orientation are like this O\ instead of like this Ol.

Most of the time with the combination of a little too much deflection, not quite enough bend (tension) and a loose firing pin stop fit, the case rim will rotate the extractor a little, and then straighten it up when the case is fully up on the breechface, and it never causes a problem...so we never even notice it. With correct deflection, the extractor doesn't clock unless tension is very low. A fitted stop guarantees it...but a tightly fitted stop WITH a little too much deflection can bring intermittent failure to go to battery problems.

And it starts to become clear how critical correct extractor specs and setup are to functioning. There's more to it than just proper tension.