1911Tuner
Moderator Emeritus
The installation, adjustment and tuning of the extractor seems to be a hot topic whenever the question of reliability in the 1911 pistol cmes up... and
for good reason. I have developed a method for addressing the potential
problems with the newer, tempered steel barstock extractors that I've had very good results with. I wrote it up and saved it several weeks ago, and
posted it on THR. It's buried somewhere, and thought since we're doing
a gunsmithing clinic, it would be worth a new thread. I've modified a few
extractors for forum members, and have had good reports. Here is the
write-up, for any who would like to give it a try.
---------------------------------
Back in the days that Colt was using spring steel extractors, they didn't have the issues that extractors have today. They were made of the right stuff, and were properly adjusted before they left the factory. Along came inflation and reduced profit margins and with them, cast extractors. Just when the limited supply of GI extractors was getting thin, we got barstock parts. Good, but not quite right. The problem was that they
didn't "spring" open. They were rigid, and needed periodic attention to keep them working. Better steels and tempering improved them, but they still weren't quite there yet.
The problem with getting the tension by bending the front of the extractor is that the steel is rigid...not "springy"...and as the case rim cams the hook to the right, the center pad...dog knot...hits the channel and creates a tight spot. Failure to go to battery. Reduce the bend, and the extractor cams open easier, but now we don't have enough tension. Back and forth, back and forth...until we hit just the right amount of bend to make it work right in both directions. 5 or 6 thousand rounds later, we had to repeat the whole process. Eventually, the steel began to work harden, and the hooks broke off, and occasionally, the whole front end would let go.
Removing about .010-.012 inch of material from the outboard pad allows three things. One, the extractor will move farther to the right before the knot hits the channel...eliminating the tight spot that causes failure to go to battery. Two, it allows the bend to be put in the center, so that the tension comes from the entire length of the stem instead of half of it. Leverage. Move the fulcrum closer to the load, and the load is easier to lift. Three, it allows a little more tension to be imposed on the case rim because of the leverage point without issues related to return to battery is reduced due to the increased mechanical advantage that comes from shifting the fulcrum.
Removing about .005 from the inboard dog knot and the front pad gets the hook closer to the centerline of the breechface. This accomplishes two things. One, it allows more of the available tension in the stem to be applied to the case rim. Two, it begins to gain control of the round earlier as it's stripped from the magazine...and it also gets a slightly tighter grip on it. This works to prevent the round getting knocked ahead of the extractor, and forcing the extractor to climb the rim. I typically set the size at the front pad at .125-.130, and have had best results within that range.
Last, the front of the hook has an angle of about 30 degrees. If this angle is formed into a gentle radius and polished, you may find that you can lock the slide, put a round in the chamber, ease the slide down until it stops, and snap the hook over the rim easily by hooking your index finger around the trigger guard and your thumb around the rear of the slide and applying about 10 pounds of pressure. This happens with most pistols, if they are close to spec. It allows the gun to go to battery more reliably in the event of a push-feed, and greatly reduces the amount of impact stress that occurs when this happens. They will ALL do this from time to time, under certain circumstances. The old spring steel extractors would tolerate it
with very little, if any loss of reliability. This is the final reason that Browning specified spring steel for this part. So that the pistol could be emergency single loaded in the event of a failed or lost magazine. Some may consider that a matter of opinion, but logic dictates that it's at least a point of careful consideration.. Would JMB really design a pistol for the U.S. Military that WOULDN'T allow for it? Would the Army accept and adopt such a pistol? The M-1903 Springfield was a controlled-feed design, too...but study the extractor just a little and you can see that it was designed to snap over if the need arose.
Luck to ya'll!
Tuner
for good reason. I have developed a method for addressing the potential
problems with the newer, tempered steel barstock extractors that I've had very good results with. I wrote it up and saved it several weeks ago, and
posted it on THR. It's buried somewhere, and thought since we're doing
a gunsmithing clinic, it would be worth a new thread. I've modified a few
extractors for forum members, and have had good reports. Here is the
write-up, for any who would like to give it a try.
---------------------------------
Back in the days that Colt was using spring steel extractors, they didn't have the issues that extractors have today. They were made of the right stuff, and were properly adjusted before they left the factory. Along came inflation and reduced profit margins and with them, cast extractors. Just when the limited supply of GI extractors was getting thin, we got barstock parts. Good, but not quite right. The problem was that they
didn't "spring" open. They were rigid, and needed periodic attention to keep them working. Better steels and tempering improved them, but they still weren't quite there yet.
The problem with getting the tension by bending the front of the extractor is that the steel is rigid...not "springy"...and as the case rim cams the hook to the right, the center pad...dog knot...hits the channel and creates a tight spot. Failure to go to battery. Reduce the bend, and the extractor cams open easier, but now we don't have enough tension. Back and forth, back and forth...until we hit just the right amount of bend to make it work right in both directions. 5 or 6 thousand rounds later, we had to repeat the whole process. Eventually, the steel began to work harden, and the hooks broke off, and occasionally, the whole front end would let go.
Removing about .010-.012 inch of material from the outboard pad allows three things. One, the extractor will move farther to the right before the knot hits the channel...eliminating the tight spot that causes failure to go to battery. Two, it allows the bend to be put in the center, so that the tension comes from the entire length of the stem instead of half of it. Leverage. Move the fulcrum closer to the load, and the load is easier to lift. Three, it allows a little more tension to be imposed on the case rim because of the leverage point without issues related to return to battery is reduced due to the increased mechanical advantage that comes from shifting the fulcrum.
Removing about .005 from the inboard dog knot and the front pad gets the hook closer to the centerline of the breechface. This accomplishes two things. One, it allows more of the available tension in the stem to be applied to the case rim. Two, it begins to gain control of the round earlier as it's stripped from the magazine...and it also gets a slightly tighter grip on it. This works to prevent the round getting knocked ahead of the extractor, and forcing the extractor to climb the rim. I typically set the size at the front pad at .125-.130, and have had best results within that range.
Last, the front of the hook has an angle of about 30 degrees. If this angle is formed into a gentle radius and polished, you may find that you can lock the slide, put a round in the chamber, ease the slide down until it stops, and snap the hook over the rim easily by hooking your index finger around the trigger guard and your thumb around the rear of the slide and applying about 10 pounds of pressure. This happens with most pistols, if they are close to spec. It allows the gun to go to battery more reliably in the event of a push-feed, and greatly reduces the amount of impact stress that occurs when this happens. They will ALL do this from time to time, under certain circumstances. The old spring steel extractors would tolerate it
with very little, if any loss of reliability. This is the final reason that Browning specified spring steel for this part. So that the pistol could be emergency single loaded in the event of a failed or lost magazine. Some may consider that a matter of opinion, but logic dictates that it's at least a point of careful consideration.. Would JMB really design a pistol for the U.S. Military that WOULDN'T allow for it? Would the Army accept and adopt such a pistol? The M-1903 Springfield was a controlled-feed design, too...but study the extractor just a little and you can see that it was designed to snap over if the need arose.
Luck to ya'll!
Tuner
.
