Extractor Fitting Class with John Travis

[MacEntyre]

I visited John Travis, aka 1911Tuner, the other day. A 1958 Colt Sistema needed the chamber reamed. While checking it out after fixing the chamber, Johnny found that the extractor was not fitted properly.

I've taken several 1911's to Johnny for tweaking, and never have I seen this problem. I've heard him describe it, but there's nothing like seeing it with your eyes. I wish I were in a position to take detailed pictures, but I am not... a word picture will have to suffice.

"There's usually more to extractor fitting and tuning than bending for tension. The deflection is critical to feeding/returning to battery." Johnny prepared to show me exactly what he's been talking about for years.

On either side of the breechface there is a wall. The round coming up from the magazine goes between these walls, and into the clutches of the extractor claw. This is the key part of the 1911 Controlled Round Feed. As soon as the magazine feed lips let go of the round, the breechface walls and the extractor claw grab it.

To make this work, the extractor is positioned to make contact with the round. Coming up, the round goes right between the breechface walls, but it actually hits the extractor and deflects it a tiny bit, giving the claw a strong hold on the rim.

In my Sistema, the extractor was too far beyond the breechface wall. It's supposed to be about 20 thousandths beyond the breechface wall. This one was closer to 35 thousandths.

What made it interesting is that the tip of the claw was in the right position. When Johnny said that, I asked why it has this problem. If the extractor was made correctly, when the tip is in place, the rest should be in place. Turns out, the breechface walls were slightly out of spec.

With the slide off the frame, you can see the extractor protruding beyond the breechface, about 3/16" of it with the claw on the end. That little bit that protrudes sits just inside the breechface wall. When the round comes up from the magazine, the rim slips under the claw and deflects the extractor.

In my Sistema, the rim of the round coming up from the magazine could not deflect the extractor enough. That stopped the round from coming up, leaving it nose down, so that the bullet struck the feed ramp and jammed.

If this problem were addressed by putting less bend in the extractor, it would pull the claw away from it's proper position, leading to other problems. So, Johnny dug out a special file that he keeps for just this situation. By removing metal from the extractor just inside the claw, the problem is addressed without affecting the position of the claw itself. Again, the cause was the breechface walls being out of spec.

So, I asked, why do not other pistols have these problems. Are they using controlled round feed? The answer is that they do it with more tolerance, a looser kind of system, so that it is less critical that things be fitted well.

Anyway, the problem was solved without changing the bend or tension of the extractor. I learned something, and had a good visit with Johnny.

Knowing that he loves Smith revolvers, I took one to show him. He opened the presentation box, looked at it and immediately shut the box. It was too much... I should have known better. But that is another story!

 

[John Travis]

Thought I swore off posting on the open forum, I'll go ahead and respond to to this one on the chance that it'll spare a few feed ramps from Dremel Dan's universal cure for return to battery problems.

Mac's pistol had a couple issues that placed the extractor's tensioning wall too far inboard. One was that the distance between the small guide blocks was about .010 inch too wide, and I suspect that it was because the one that the extractor passes through was machined too much. Just by my eyeball micrometer, the side opposite appeared to be okay. That alone makes it necessary for more of the wall in the breech area than I like...but we usually have to work with what we've got.

The other problem was that the extractor channel itself was either slightly angled toward the center or a few thousandths oversized. That the forward pad on the extractor was on the large side of spec suggested one or both with the tolerances stacking up in the wrong direction.

The result was that there was about twice as much of the wall in the breech than there needed to be, and about three times what I work toward in fitting an extractor for smooth, reliable feed and go to/return to battery. I like .010-.012 with a maximum of .015 inch, but due to ther guide blocks on this Argentine Colt being too far apart, Mac's wound up at around .005 above maximum.

Finally...looking at the extractor...it was apparent that somebody had diagnosed the cause for the intermittent failures to go to battery and had jacked the extractor up very nearly past the point of no return by heavily radiusing the lower edge of the wall and the claw itself. If he'd persisted for a couple more minutes, the extractor would have been killed.

After the wall was adjusted, I had to shorten the claw a little to get the correct depth into the case extractor groove and was able to reestablish the correct shape on the claw...barely.

A heavy radius or bevel on the wall's lower edge has become the Bubba fix for people who recognize the problem with too much of the wall in the breech area in the attempt to create a camming surface for the rim to spring the extractor open, but when it's radiused or beveled too far up on the wall, causes problems with ejection...even to the point of the wall losing contact with the case rim when the barrel starts to drop, pulling the case down with it. This shows up as erratic ejection and crushing the last round between the slide and barrel hood when the claw stuffs the case partway back into the magazine...keeping the slide from locking open...and crushing it when the slide runs forward again and tries to feed it into the chamber.

When the extractor is correctly fitted, no radius or bevel is needed beyond lightly breaking the bottom corners of the wall and claw.

The moral of this story:

If you have an occasional failure to go to or return to battery...look to the extractor first. That's very likely where the bug nests.