Stem Bind with my Springfield 1911

[FullEffect1911]

The other day i was shooting my Springfield 1911 and got a few failures to return to battery.

The rounds would not feed with a nudge/hit to the back of the slide and would feed instantly when I dropped the clip. After inspecting the cases there is a creasent shaped mark near the case mouth. I have determined from reading about such jams that this is indeed a 3 point jam. This jam only occured with the top round of a fully loaded mag and only when droping the slide with the slide release.

-Mags are good
-extractor was checked and cresent mark will still occur on brass without the extractor in place
-no discernable burrs on the feed ramp.

This leads me to believe that there is a lower lug issue or a link issue, however i am having a hard time figuring out what to do here.

I have to assume that it should feed without leaving a mark on the brass like that?

Any pictures on a proper fix/mod or instruction would be greatly appreciated.

FE1911

P.S. Also the brass seems to stike the top right of the ejection port and leave a brass mark just on the outside, what is going on with that?

P.S.S. I'm really considering just getting a stainless mil spec with the money from selling the fully loaded. Planned on replacing a lot of the internals anyway. sigh

 

[HSMITH]

It sounds to me like the magazines are letting the top round up too high. Have you tried different magazines? It could also be a mag catch being too high but that is very unlikely.

Don't worry too much about the brass marks on the slide, lots of very reliable guns do the same.

 

[FullEffect1911]

glad to know about the brass marks, thanks for that.

I read a couple of things written by tuner, and had some magazine troubles worked out. How tuner describes the 3 point jam on 1911.org is exactly what is happening. However i am unsure of how to proceed with the solution. Extractor tension is good, mags are the springfield with an 11# wolff spring upgrade, they have the flat followers with the bump, and they seem to be in spec.

If anyone knows where i can find very detailed instructions on how to fix stem bind (preferably with pictures) i would greatly appreciate it.

I ordered both Kuhnhausen 1911 manuals, so i can check out what the actual specs are supposed to be.

 

[1911Tuner]

Stem Bind

Several things can contribute to a stem bind. Some simple to correct, some more involved.

The first place to look is the corner at the top of the throat, where the barrel turns from ramp into chamber. Sometimes it's a simple matter of scraping a LIGHT 45 degree bevel there...and polishing with 600-grit paper on your finger. You can use the tip of a small pocketknife for the job. That reduces the angle of entry into the chamber and makes it easier for the round to break over to horizontal.

The next place to look is for any roughness on the breechface. Polish lightly with 600-grit paper on a popsicle stick cut to fit. Look into the chamber too.
Check for roughness or toolmarks, and have the chamber checked for size and
taper. I've run into several top name match barrels that tapered toward the front, and whenever I drop a finishing reamer into these barrels, I almost always get some chips from the front third. Occasionally, I find that the whole chamber is a little undersized.

Measure the width of the breechface guide rails. Two parallel rails seen from underneath, with one that intersects the extractor. They should be a minimum of .484 inch. I like .488 to .490, and some smiths will go a little wider there. Don't go with the idea that more is better. Too wide lets the round shift sideways when it hits the extractor, and can bring on a lateral bind. Use a small flat, safe-sided file to bring it to size and cut a very light bevel at the bottom corners to help funnel the round into place. This is very likely your bug. To test, find somebody who has a few rounds of Wolf ammo.
They typically have rim diameters that are on the small side. If those feed smoothly, that's indication of the rails being too narrow.

Check to see if the barrel rides the link as it cams up into vertical lock. It doesn't have to stand on the link in lockup to ride it around the front radius of the lower lug. This tends to bring the barrel up too early and abruptly,
throwing the round into a bind before it gets into the chamber far enough to break over easily. The top of the slidestop crosspin hole can be relieved a little if this is the case. No more than about .003 inch though.

Finally, the barrel may be sitting too high in the bed, causing the round to start into the chamber at too steep an angle. This one requires care and patience to do without ruining the frame. Radius filing the bottom of the barrel behind the lug can help, but it must be carefully done for a maximum of .003 inch. Don't cut a sharp corner into the radius at the junction of the barrel and the rear of the lug. The other part involves careful material removal in the frame bed itself...for a maximum of .003 inch, and the possiblity
of having to set the bottom of the barrel throat forward and reshaping the throat. If you're not familiar with this one, I suggest taking it to someone who has done it, as it's easy to get into trouble here.

 

[FullEffect1911]

Thanks once again tuner

 

[FullEffect1911]

One thing, i assume that a properly feed 1911 should show no cresent marks on the brass correct?

 

[1911Tuner]

Crescent

Correct. They may show a light scrape, but gouges are indication of a problem.

 

[FullEffect1911]

RIGHT!, now all i have to do is get out of work to get started on the fix :banghead:

Thanks again tuner.

 

[FullEffect1911]

Follow up to Fixing the bind

Tuner,

After trying all of the simple stuff first i had to elongate the barrel link as per your instructions on m1911.org. I brought the barrel link's radius closer to the lower lugs radius and the slide release pin is lightly touching when the pin and link pass the lugs radius. This substantially reduced the creasent marks that were being made in the cases. I have yet to test fire the new improvement as i wanted to find out a few things first.

Since elongating the slidestop pinhole, the slidestop pin now has a very sloppy fit in the slidestop pin hole (as was expected really). Will this cause any problems seeing as how that now has play in it? Should I get a slide stop with a bigger diameter pin to fill up the spare space?

Also the lug pin is not much of press fit and i plan on getting a proper size pin for getting said press fit. However are springfield links good or bad? Should i just replace the link and start from scratch with good parts?

At least i think i got rid of most of my stem bind, but i wanted to make sure everything else was still kosher.

As always thanks in advance, and i look forward to hearing from you.

FE1911

P.S. it felt absolutly wrong taking a dremel to the link ...but thats what the instructions said

 

[setxcypress]

F.E.1911, I know how you feel. I'm dreading the day that I might have to make a modification to mine. But then again it has run smooth from the box for about 750 rounds with just two malfunctions. They were both magazine related and consisted of not locking open after the last round. The follower in the Kimber mag couldn't reach the slide lock and after a little bending, works just fine.

But then again I know that there will always be a bad apple of the group and some 1911s just don't know how to behave.

 

[FullEffect1911]

yeah i had some mag issues early on, but i gotta tell ya stem bind sucks. I love the gun but every little change can affect something else, thats why i want to know about the mod to the link.

What kind of 1911 do you own setxcypress?

 

[1911Tuner]

Sloppy Pin

Howdy Full Effect,

The looser fit won't make a difference unless you elongate the hole on the bottom...which accomplishes the same thing as installing a longer link and delaying linkdown timing. All you've done is to move the slidestop pin closer to the lower lug radius without using a shorter link...which can bring on other problems sometimes. As long as the barrel is locking on the lug instead of the link, nothing will change, except the rate of barrel rise as it cams up into vertical lock.

Lightly scrape a radius or bevel into the the top corner of the throat and polish with the 600-grit paper, and your stem bind should be cured.

Luck!

 

[FullEffect1911]

Good Morning Tuner,

I did the bevel and polish of the throat before i did the link mod. All and all, whatever bind is left is only putting a very like slight creasent scratch, not that bad at all really. Much better from the cresent dents it was putting in the cases. Breech face is smooth as silk, however the breechface guide rails are a few thousanths over what you recommend through no fault of my own (factory jobber )

However what is concerning me is this:

When the slide is back and the link is at a 45 there is light touching the lower lug radius even with elongating the link (good, i think). when the slide comes forward there is no touching right up until it reaches full lockup. At full lockup the pin becomes slightly snug up against the lower lug, this isn't tight up to the point that it is super tight, it is possible to take the pin out but I can feel the resistance. There is also some marks on the slidestop pin where it is lightly contacting the lower lug, on mark in the middle from the link and two on either side from the lug. Like i said it isn't major markings but the finish is worn there.

I assume that it is riding the link a bit but how bad is this?

 

[1911Tuner]

A Little Tight

FE...Sounds to me like all is as it should be. The slidestop pin is forced into the lug's back radius by the recoil spring tension when the gun is in full battery. As long as the barrel isn't standing on the link when it's in battery, all is well. Even a slight amount of locking on the link is acceptable, and a good many factory barrels do that. Not correct, but kinda okay as long as it's not excessive...or not more than about three or four thousandths of an inch...about the thickness of a sheet of typing paper. You can determine that by holding the barrel up and swinging the the link into battery position
with the back curve of the lug aligned with the rear radius of the link's hole.
Visualize the slidestop pin thru the link. If the link would hold the pin off the lug, it's standing on the link.

From your description of two marks from the lug and one in the center from the link...it doesn't sound like you have that condition. test-fire it to see if the return to battery problem is gone. My bet is that it's a done deal.

 

[setxcypress]

Springfield Armory full size Mil-spec in .45
The SA model number is PB9108L
I'm itching for another because this one has been a great experience.

 

[FullEffect1911]

those mil specs sure are nice, i was thinking of getting on and doing some work on it to get it to what i want, but my loaded should be fixed up and ready to go now so i don't have to replace her.

If you have doubts about the mil spec/gi .45 take a look at 1911tuners tourture test on the GI .45, that will relieve any doubts you have. That is assuming you haven't read it already.

When he tests a gun he TESTS a gun. Good review all around though.

here is a link to it

 

[setxcypress]

I may modify my second if I can get a good deal on one, but she's my first and will always stay the way that she came from the factory.

I have done what could be considered a test, but nothing of Tuner's magnitude or wanton destruction . My first test was done out of ignorance. I forgot my oil at the house and ran her dry for about 100 rounds. No problems at all. I think that test solidified my love for her.

The second thing that makes me love the 1911 is the simple trigger and firing mechanism. Took everything off of mine that can be taken off with a screwdriver or a pin, all told, the part count ran to the low forties and that was counting the grip panels and screws. I don't think that I could detail strip a glock or even my friends Bersa Thunder .380 and get it functional again.

That's something else, I shot my friends Star BM in 9mm and my other friends .380 and the recoil was a bit more noticeable than with mine. But then I think the Star has a 4" barrel and the Bersa a 3". And then there is my monster of a hand cannon with the 5" barrel throwing almost a half inch slug down range. You would think that he 1911 would be the worst on recoil just looking at size alone. Nope, my friends sister shot his Star and my .45 and said that just looking at them she thought mine would tear her hand up but after the smoke cleared, she liked mine better.

But hey, I ramble and digress at times.

 

[1911Tuner]

Tools

Quote:

>Took everything off of mine that can be taken off with a screwdriver or a pin.<
*****************

Ya don't need even those things to get one apart. I use an AR-15 firing pin
on the bench, but in the field, the gun is its own tool box, though there's some reservation over using the cast or MIM thumb safeties for mainspring housing pin.

 

[BluesBear]

In the old days the Colt instructions that came with every Model O pistol told, in detail, how to disassemble the pistol with no tools.

Or you could get one of the original takedown tools to make it slightly easier.

 

[setxcypress]

I did replace one thing on mine when I first bought it, and that was a steel firing pin from brownells and a new firing pin spring. I thought I would have a FTF from the TI pin not traveling forward enough.

I did a detail strip just for S&G, followed BluesBear's guide, and didn't need a single tool other than the firing pin, the grip safety, hammer strut, and the sear spring.

Thanks BluesBear for the link, and Tuner too.