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Old February 13, 2013, 01:11 PM   #26
Unclenick
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One last test to see if it's the link. Repeat test 1 with the gun upside down. Does the smoothness of the slide operation go away? If turning it upside down does terminates the smooth function, the link has stretched and is not pulling barrel down quite early enough in the cycle timing. That would vindicate HiBC's observation.

The reason I think this drag happens when the case is in place and the gun is upright is the extractor tension against the brass is likely enough to prevent gravity from assisting the barrel to drop out of locked position. It's hard to imagine how the extractor tension alone could add 10 lbs to your effort, though you can always polish the inside surface of the extractor behind the claw and round its corners a little. Same for the inside back surface of the claw, but just don't dull the tip of the claw.
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Old February 13, 2013, 06:35 PM   #27
DMK
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Quote:
One last test to see if it's the link. Repeat test 1 with the gun upside down. Does the smoothness of the slide operation go away? If turning it upside down does terminates the smooth function, the link has stretched and is not pulling barrel down quite early enough in the cycle timing. That would vindicate HiBC's observation.
Flipped the gun upside down, no recoil spring, no shell in the chamber. The slide comes back almost 1/8 inch then I can feel it catch on the barrel lugs. It's quite not as hard to overcome the resistance as it is right side up with the shell in the chamber, but there is a definite catch there. I can feel the interference of the lugs.

Just to validate for my own sanity, I tried the test on my Argentine Sistema. There's definitely a big difference. Plus the Sistema starts to unlock immediately upon moving the slide, where the Star has that 1/8 inch of play where the slide moves back before it even tries to pull on the barrel.

So does a barrel link require fitting, or should it be a drop in replacement?
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Old February 14, 2013, 05:46 AM   #28
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I'll leave that to Uncle Nick,I'm just a rookie!
But,IMO,There is original John Moses Browning intent,there is getting it all just right,and there are also tolerances and a whole lot of guns that work,but aren't quite right.

As I said,I only have a couple builds worth of experience.I just figured I would buy and scrap fewer parts,and would be more likely to make a good handgun if I first studied how the thing works.

I recomend getting Kunhausen's shop manual for a 1911 .Brownells will have it.

As simple as it looks,a lot is going on .
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Old February 14, 2013, 02:48 PM   #29
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May or may not be a drop-in replacement. You can try a standard 0.278" link. But other spacing is available, and you should be prepared that it may not match perfectly.

As an alternative, you'll find there are link kits that have several links with different spacings between the holes. This will let you try several.
Directly measuring the right size takes a special tool, so the kit is easier to let you test different lengths.

If we assume the new assembly pin hole will be tighter on both sides, you'll have four things to watch for:

1. It passes the previous test.

2. It doesn't jam the barrel locking lugs up against the slide lug recesses.

3. It doesn't jam the back ends of the link lugs on the barrel into back end of their cutout in the receiver cradle. When this happens it prevents the barrel going fully down into the cradle in the receiver (full counterbattery position). If you are holding the frame without the slide on it but with the barrel held in place by the assembly pin on the slide stop and the barrel rocks fore and aft no matter how firmly you are pushing it down into the cradle, the link is too long or you need to file the breech end of the link lugs forward until it fits. Otherwise it may rub the slide or fail to allow the gun to unlock it completely.

4. It doesn't force the feed throat on the barrel to overhang the magazine well. If it does and you like the fit otherwise, you are in for reshaping the back of the barrel and the feed ramp extension (throat) cut into the bottom of the mouth of the barrel, which takes a bit of skill and knowledge about correct fit (read Kuhnhausen). Allowing it to overhang the feed ramp can interfere with feeding.

Link kits on Brownells. These are for standard 1911's, but I presume they will fit your gun as well.
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Old February 14, 2013, 03:31 PM   #30
Bill DeShivs
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The Star is not a 1911.
I seriously doubt 1911 links will work.
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Old February 14, 2013, 08:18 PM   #31
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Yikes!. That link just looks so much like a 1911 my brain switched to 1911 autopilot with that kit recommendation. Also, now I look a little further into the parts places, I don't see Star links listed anywhere as separate parts. The Numrich schematic doesn't number them or the pins separately, but rather shows them as part of the barrel assembly. I also notice from DMK's photos that the metal finishing marks match clear across the pin. That and the lack of available replacements makes me think that link may be matched to the barrel at the factory and is meant to be permanent.


DMK,

A couple of things come to mind. First, you might get away with just breaking the edges on the barrel locking lugs and recesses. This would mean taking a sharp triangle file and putting a very slight 45° chamfer on the edges of the barrel locking lugs and using a scraper (a small triangle file with the teeth ground off to form a sharp edge) to put them on the edges of the lug recesses in the slide. These might only need to be a couple hundredths of an inch across. Just enough to spoil the catch of the edges you feel now.

If that doesn't cut it, take a caliper and measure from the center of the link pin to the center of the assembly pin hole. See if that looks like .278". Measure the thickness of the link and of the assemble pin. See if you can push the link pin out of the link lugs and measure it. These bits of information will tell us how close 1911 lugs match the Star.

I've always made and heat treated my own links to get a perfect match to freshly cut link lugs, so this is possible to do as a last resort. But let's not try to have you go that far at the outset.
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Old February 21, 2013, 02:43 PM   #32
DMK
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First of all, I'd like to again thank everyone who helped with the excellent diagnostics and troubleshooting tips. It is much appreciated.


Quote:
A couple of things come to mind. First, you might get away with just breaking the edges on the barrel locking lugs and recesses. This would mean taking a sharp triangle file and putting a very slight 45° chamfer on the edges of the barrel locking lugs and using a scraper (a small triangle file with the teeth ground off to form a sharp edge) to put them on the edges of the lug recesses in the slide. These might only need to be a couple hundredths of an inch across. Just enough to spoil the catch of the edges you feel now.
This sounds a little scary. Are there any drawbacks to doing this? (You do just mean chamfer the lugs on the barrel, not the slide right?)

I know I do have a spare barrel link for a Sistema somewhere. If I can find it, I'll compare the Sistema and Star link with a micrometer.
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Old February 21, 2013, 04:04 PM   #33
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If there is any trace of steel that has peened up high at the edge of the lug,I would carefully dress that down to the original surface.

If that edge is dead sharp,,I might just break the edge with a three thousandths or so corner break.

I'm not the expert here,but I would not put a larger (such as a ten thousandths) corner break on it,but that is just my opinion.

Its great that you may have a new link.

Before you install it,I suggest you get the best center to center distance you can on the holes.

If you have calipers,usethe outside jaws to get a measurement of the web between the two holes,then use the inside jaws to measure the widest span of the holes.Average the two numbers,and you will have a measurement to write down.That may come in handy later.
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Old February 22, 2013, 10:16 AM   #34
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DMK,

I didn't spot any obvious battering in your photos, but you should look for it with eyes and by finger tip feel, both. You can glue 320 grit wet/dry paper to a piece of 5/8" cold rolled steel rod and use it and a little oil to iron over the slide lug recesses and level any peening there. On the barrel careful use of a fine file loaded with chalk to keep the cut smooth will take care of high spots.

Edge breaking is a common tune up technique for reliability packages. You do it to both the barrel and the slide so you have mating surface corners that are angled to slip off of each other rather than try to bite. The reason you can get away with it is there is excess engagement in the gun. Hallock's book puts the break at the front edges in the 1911 to make camming into battery easier and he limits the chamfer to 25% of the lug height. I'm not suggesting you go that far. Just a couple or three light passes with a fine triangle file on the barrel lugs and breaking the edges. Not a lot more than dulling the edge.

Another thing you can try is to re-purpose the old S$W revolver armorer's school trick of making up a slurry of JB Bore Compound and well shaken (to get the Teflon into suspension) Break Free CLP. Slather that into the locking lugs, assemble the gun upside down as you had it in the test, then just open and close it a bunch of times. This not only polishes the dragging surfaces, but works the Teflon down into them, which leaves them sort of waxy. I've done this with other Teflon bearing products, too.

Those two actions won't hurt anything, but if you still can't get it to behave, then getting a correct link in place becomes necessary to figure out.
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Old February 22, 2013, 10:51 AM   #35
DMK
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Thanks guys.

I understand what you are talking about now. I'll take a closer look at those lugs and see if I can find that Sistema link to compare.

This is a cool old gun and I appreciate you guys helping me getting it back to shooting condition again. It kind of reminds me of working on an old classic import car. Parts are unavailable, so you have to do the best with what you've got.
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