Order of Fit: slide, frame, barrel & bushing

I received my reduced mainsprings yesterday from Wolff - 20, 21 and 21#. I shoulda checked the mail earlier because I had just finished putting the gun together for a little "it looks like a real gun" time. I still haven't gotten the bushing turned and locked yet, I'm waiting on the bushing wrench I had to order. I couldn't find the one I thought we had around here :rolleyes:

I did tootle around with the sear and hammer yesterday. I pulled out my flat stone and touched up the hooks on the hammer. I also smoothed them down a bit to .020"-.021". As much as I can see the hook is at 90*, but I will go through everything again to be sure I wasn't crosseyed. Then I took the sear and began putting both angles on it. I got the angles close for "trying out" when I checked them on the frame, so I decided to put the gun together to see how things felt. Several obervations now, that were also present when I first received the lower:

1. There is play in the trigger, several mm regardless if hammer is down or cocked.

2. There is play in hammer between down and halfcock


When I first received the lower, I tried out the trigger and feel and it was ridiculously heavy/hard/stuck. While I had the gun broken down, I cleaned up all holes and tunnels with some JB Bore compound. The MSH was especially gritty, the disconnector tunnel bottom edge was nicked - things were just rough, so I got them smoothed out.

I've also got the barrel close to fit, although I'm unsure if I'm completely in lockup and how much lug engagement I have. I need to get some clay strips to smush in there to check. I did put things together and did a flash hole test. The hole is pretty close to even, although it still looks a bit shy. I Sharpied the slide lugs and grooves and I am not getting contact from the slide. I did break the lugs a hair and smoothed the slide lugs and things are clear. The barrel does overhang the feed ramp so I will have to get that moved back. I had to work on the barrel face a bit as the slide shoulders were getting battered. I also had to touch up the rear barrel lugs as they were contacting the frame before the barrel bedded. I paralleled them a little better with the barrel hood as that was off. I'm still using that Randall barrel I picked up on the fly. Again, I'm not too worried about putting a file to this. If I goof it up, I'll just get another barrel and have another go at it. Am I going about the barrel fit alright? Or am I off?

Anyway, here are some pics.

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As you can see, there are a lot of details I can get better at, especially cosmetics. But I think that will come to me as I get use to working on the gun, get use to the techniques and such.

I have the gun broken down again and I'm having another go at the sear angles. Like I said, I do have a McCormick sear and hammer on the way so I have less fear working on these. Plus, the gun wasn't in good working order when I got it, so any improvement I get out of this will be great! :D

So things you see on here I can do better, please chime in. I know I'm missing stuff.
 
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Shorts,

I am attaching a PDF file showing the busing locking lug trimming. For the first step use a flat needle file. For the scraping steps, take your smallest square needle file (small enough to fit between the lug and bushing collar) and sharpen the tip at 90°. This takes awhile because the file is so hard. It also can chew into your stone, and for that reason I like to use the side of the stone rather than the regular sharpening surface to do this. I also like to use spray adhesive to stick wet/dry sandpaper down to a square of plate glass for specialty sharpening. It gives you a flat surface and you can replace the abrasive when it wears out. It also lets you progress through finer grits for completing the job: 320, 400, 600. I use it with water or light oil; this yields the best edge.

You can radius the corners slightly on the file tip to prevent gouging. What you end up with is a push scraper. Think of a scraper as a single-tooth file, and it will make some sense. You push it in from the side to hit the spots metal needs to be removed from.

More later.

Nick
 

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Great pdf UncleNick. That's just what I needed. I'm getting tired of looking at my unlocked bushing :o ....now, only if my wrench would get here. My favorite gun shop is closed for another week so no where on the island to buy for instant gratification.
 
Dave,
Yes I do know.

Bill,
I would like to take the time to finish our discussion and answer your questions but I don't feel this to be fair to Shorts.

Shorts,
After viewing your pictures you want to make sure the bottom of the barrel ramp (commonly called the throat area) is not even with the top of the frame ramp.

As for the overhang of the slide at the rear. After making sure you have the proper lower lug and radial lug engagement, the frame impact and barrel impact area is correct so the gun will be timed correct then you can correct overhang. This is done by blending the rear of the slide with the rear of the frame.
While on the subject of timing I measure all the barrel links I use. I do not go by the number that may be stamped on them or the package they came in. I measured one that was suspose to be .278 the other day it turned out to be .2844.
Also this would be a good time to measure the spacing of the radial lugs of your slide and barrel, as they do effect the timing. For optimum performance and barrel life they should measure .324 and .649 respectively. The first thing I do with a new slide is measure the radial lug spacing, I've had some that were to far out and they went back for replacement. If you are not sure how to do this you can contact me at the shop and I'll explain it to you.
Good luck with your project.
Regards
Bob Hunter
www.huntercustoms.com
 
Bob, good catch on that feed ramp. That could have been a big problem for Shorts. I assume she's going to need to change the barrel chamfer/ramp angle to a steeper one?



A couple of points on MIM:

1. It is BOTH a process for creating a part, and a type of final product. MIM created steel parts have qualities that are unique to that process.

2. With respect to Dave's good fortune with CMC parts, I would point out that all Kimber's are advertised as also being built with CMC parts, and have a woeful reputation for those parts breaking. So unless Dave is claiming that CMC makes different parts for aftermarket than in the production Kimbers, I can't see how he can deny that these parts have a spotty reputation for durability. They may not be any worse than cast, but certainly aren't as strong as the best forged parts.

3. I would be greatly surprised if precision drop-in dimensions of the CMC parts couldn't be found in at least one forged tool steel product from C&S, Brown, EGW, Nowlin, Masen, STI, Briley or Wilson. They do cost more than the CMC parts, but at only about 2% difference in the cost of a $2000 gun, this seems like money well spent.
 
Bob, thanks for the input. The ramp and overhang had been staring me in the face the whole time I was getting it to where it is now. But now I'm getting to the point in the build I need to address it. I'm still scratching my head about it. And for now, I'm letting it be until I get the barrel into full lockup. I think it will be a bit of a bear to get right though.

I measured things last night and the barrel and slide are still shy of a good tolerance. I've been trying to understand the lower lug adjustment/link, but I'm still not totally unerstanding the process and what it does in the frame.

As for the link itself, what is the proper way to measure it? It has crossed my mind a time or two as I was doing link downs on the frame "maybe my link isn't the right size?".
 
Shorts,

There is an interdependency here. If you have your link lugs sized so that, without a link, as you push the slide into battery (barrel and loose bushing and assembly pin in place) the bottom portion of the lugs move up onto the assembly pin like a car going over a speed bump, and at the apogee they plush the barrel lugs into full lock. At that point, the recurve in the barrel lugs should run into the assembly pin and stop the slide from going any further forward. Often these are cut so the back of the slide overhangs the back of the frame by about 1/64". This leaves you room to re-cut the link lugs a little later to compensate for wear.

At this point you can size the link itself. Put the pin in place and let the link drop down. The hole through it should just kiss the link lugs along a quarter of the circumference from 12 O'clock back to 9 O'clock if you hold the barrel with the muzzle horizontal and pointing to the right.

You can also take your calipers and use the outside jaws (the main ones) to measure the web between the pin hole and the lug surface at 4:30. This should match the web measurement of the link. If your link is too small or too long, the gun won't go into battery as it did without the link in place. The short link will hang up on the link lugs, while a long one will try to push the barrel up too far and jam the gun just short of battery. Test this using Dave's gravity feed approach. If you force the gun into battery with a long link, you will be prying the rails up with the slide.

I always make my own links from ground oil-hardening tool steel bar stock and double heat treat, drawing it twice to 800°F. This yields a Rockwell hardness of about 50, which will take the hammering without cracking or deforming. You should probably invest in one of the kits of different length links from Brownells while you save up for your heat treating oven.

Your barrel needs to be re-throated at the feed ramp. You can do this with a Dremel tool and the carbide cutter they sell which has spiral teeth (not the tile cutters with cross-cut teeth), followed by Craytex tips to polish. Mark the outside of the barrel under the feed throat with Magic Marker. Put the gun and link together (you need to establish the link size first). Push the barrel back into counter battery position and use an opened safety pin to hook up under the overhand and scratch a demarcation in the magic marker. You will whittle down to that size and maybe 1/64th over. Under-hang is better than overhang, since it doesn't stop feeding.

Nick
 
I have been advising Shorts via PM's and have not commented much on nthe forum. I have been busy getting 1911's ready for the bluing tanks this weekend and have not had much to say.

Shorts has undertaken a project that would scare me, and I am fearless. She went ahead and purchased all of these parts without any input, and I presume they came off the Internet for the most part. She is using new parts mixed with well used parts with an officers lower end well used and with a 45 ACP feed ramp. Her barrel is a used Randall and they are a failed enterprise so I have no idea of what that barrel will fit up as. She is a very tough, likable woman and I will help her all I can, but I am trying to keep her in first grade, not in senior high.
I think a lug cutter would be a huge help in fitting that barrel as the whole top end needs to be moved forward without touching the barrel throat until she has the slide lined up with the lower end. This is a touchy job that needs some one like Bob or Uncle Nick to step in and get her past these rough spots. They have both joined in the spirit of the game here and could make life a lot easier for this gal with some tools that a one time builder should not need to buy. I , too, would offer my help here if she wishes to avail me of my previous offer.
I have the tools here to do a 30 minute job for her if she wishes to get out of the jam she is presently in.
The other way to cut lugs here is to use a chain saw file which is the way I fitted barrels for many years and still have that file here in my shop.

WE are going to finish this Job come Hell or High Water , Shorts! I have spoken!
 
WE are going to finish this Job come Hell or High Water
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See, that's the kinda attitude us Texans are raised on. "What do we need to do? Ok then, let's go do it". What a breath of fresh air :cool:

Gosh, now I'm all self-concious wondering if I am the fool with this project :o If it works, I'm the fool with a fun gun! :D

All the parts in the lower are used, the frame came complete. All the parts in the slide, including the slide and barrel, are new. I have new mainsprings, hammer and sear I can upgrade to. If need be I can replace everything else in the frame.

UncleNick, great writeup on the lugs and link. I drew a picture of your explanation so I can put an image to everything. Did I interpret everything correctly? (lol sorry, I'm a visual/hands-on learner)

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1. There is an interdependency here. If you have your link lugs sized so that, without a link, as you push the slide into battery (barrel and loose bushing and assembly pin in place) the bottom portion of the lugs move up onto the assembly pin like a car going over a speed bump, and at the apogee they plush the barrel lugs into full lock. At that point, the recurve in the barrel lugs should run into the assembly pin and stop the slide from going any further forward. Often these are cut so the back of the slide overhangs the back of the frame by about 1/64". This leaves you room to re-cut the link lugs a little later to compensate for wear.

2. At this point you can size the link itself. Put the pin in place and let the link drop down. The hole through it should just kiss the link lugs along a quarter of the circumference from 12 O'clock back to 9 O'clock if you hold the barrel with the muzzle horizontal and pointing to the right.

3. You can also take your calipers and use the outside jaws (the main ones) to measure the web between the pin hole and the lug surface at 4:30. This should match the web measurement of the link. If your link is too small or too long, the gun won't go into battery as it did without the link in place. The short link will hang up on the link lugs, while a long one will try to push the barrel up too far and jam the gun just short of battery.


I measured the lug width at 430 and it is less than the link width. I also ran the link along the lugs checking for #2 up there, contact is good at 12 and 9, but there is no contact at 10-11.

I also put the barrel in the slide and put on the frame and slid it into lockup. The slide overhang that is present with the link in place is also still present without the link.

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So it is all broken for good??
 
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You have plenty of meat on those lower lugs, Shorts. Imagine if they were a little thinner up front but with the same curves. The slide stop is where the lugs stop the forward movement of the slide. When we fit the barrel, we sometimes need to cut them up as we cut them BACK. When you cut the lower lugs back, the slide moves forward. We use a lug cutter that goes in the slide stop hole and then we force the slide forward slightly until it all lines up, including the disconnector notch which needs to be in the right place, also. Then we finish the job with small files until it will pass the gravity test. This test will be very important on this particular gun because of the caliber and you shooting it with your right hand only. We may have to tweak the springs to get the right amount of recoil for the way you shoot it. All semi autos have to have resistance to function and that is why we try to hold them hard and step into the recoil without fear.
You are a great person and deserve all the help we can give you. If we can't make this work, I will send you a Star BM Commander 9mm to play with forever. My daughter has one just like it, only the pimp version.
By moving the lugs forward we cure part of the overhang at the same time. So keep up the good work and remember that you must be very patient with yourself when working with metal. Crawl first, then walk ,and then run with the Big Dawgs! They get easier everytime you build one so don't despair. This one is a Piece of Cake!
 
Thanks Dave :)

So with plenty of material left on my lugs, that's a good thing for further fitting correct?

I am seeing a bit of new light. Setting the barrel in the slide in lockup position and then putting my finger on the barrel and applying downward pressure backwards and forwards, the barrel seemed to be rocking on a high point in the slide lugs. It seems that the rear most slide lug wasn't even with the rest. I remembered a reference in Kuhnhausen where they took a lug leveler, just a round straight iron they used to even the lugs. So, I got out my dowel, wrapped some paper around it and began smoothing the slide lugs out.

I sanded...checked barrel movement..sanded...checked movement. When things got noticeably better (although still a touch of movement), I assembled slide frame, link and slide stop and took measurements of lockup again. I did this both with and without the link. This seems to have helped lockup, as my numbers were consistently running between .054-.056 with link and .050 w/o link.

The slide lugs are working a bit more in unison. I'm still marking things up and checking the fit. It's not there yet, it was nice to make a little progress.

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The rear of the slide still seems to be close, with and w/o link installed. Here's a comp of the two. Sorry I couldn't make the variables of the camera distance any better. It's really hard to tell the difference. Oh yeah, how about that nice rear end bulge of my slide?? :rolleyes:

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hehehehehe my Brownell's order just got here :D And it took all of 30sec to finish turning the bushing to the slide. Hmm, why didn't I get one of these sooner? It's the King's bushing wrench, that's hefty!
 
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most interesting... :) I'm anxiously awaiting the barrel ramp/throat issues, myself, since I've been through this with my 9mm LW Commander that I converted from .45 a couple years ago.

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Kindly quit laughing at my dremel work :D it's an Ebay barrel, and next time I'll set up a mill. The LW Com does feed, and so far it shows no signs of case bulges, even with +P Corbons in a tightly headspaced barrel.

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At the time I was building this I could find no references, nor educated opinions about how much throat one could have on a 9mm 1911, so I had to go slowly and make reasonable guesses. If someone can share more experience, it would be appreciated - by me and probably by Shorts, too.
 

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Dave,

Thanks! I've got a better picture of the project now.


Shorts,

Your illustration of my lug description is close, but exchange #1. with #3. for the corresponding measuring location for the link web. Your first lug photo shows the link to be about right for the lugs as they are currently cut, so the question remains whether they have more material to be removed? The illustrations of the slide in battery show there is no extra material to be removed at the leading edge of the lug feet (bottom part that stops against the pin going forward. I say this because I can just make out a little of the frame peeking out from under the back of the slide. You don't want the slide further forward or you may have to start scraping more length into the disconnector depression in the slide to keep functioning.

Next test: With the frame in your leather-line vice, assemble the barrel and slide and try-bushing (the loose one) together as you did before; no link. Put the assembly pin in and push the gun into battery. Now put about a one foot length of 3/8" wood dowel into the muzzle and push down on the far end to see if the barrel moves up and down any at the ejection port, or if it is tight? If it doesn't move when you bear down on the end of the dowel, this is good. The back of the slide should be held forward with thumb pressure while you do this.

If there is barrel movement, then your lugs are already short and there is nothing left to cut. In this case you would need a weld-up done to the lugs to give you material to tighten them. This is a job that has to be done by and experienced welder. I shudder when I remember a picture of Bob Day with an acetylene torch adding magazine spring material to the lugs of a barrel without any obvious chill in place. Only a very skillful welder can get away with that. I would rather you have a good TIG welder do it if it must be done.

Alternately, you can simply install an oversize lug to swing the barrel up further. This doesn’t afford quite such good consistency as fit lugs, but the link will be the right length if you decide to weld up the lugs later. Sizing this link becomes more problematic than my earlier description. Probably the simplest method is to start by making a depth measurement of the top of the barrel chamber from the top of the ejection port with the caliper's depth stem. Do this both with the barrel as far up and as far down as the dowel moves it. Take the difference in thousandths and jot it down for the next step.

Links are measured by the center-to-center (c-t-c) distance between the holes. You already measured the web. Now stick the sharp little inside measuring jaws on the top side of the caliper into the link holes and see how wide open you measure the outside edges of the holes to be? Add the result to the web thickness and divide by two to get the c-t-c hole spacing. Add the barrel elevation change jotted down in the last paragraph to this c-t-c number to specify a new long link from the Brownells catalog.

More later.

Nick
 
tex-n-cal, the pic of the barrel ramp, is that sitting even with the feed ramp or is there a little gap betwen them? I can't tell from the angle.


Next test: With the frame in your leather-line vice, assemble the barrel and slide and try-bushing (the loose one) together as you did before; no link. Put the assembly pin in and push the gun into battery. Now put about a one foot length of 3/8" wood dowel into the muzzle and push down on the far end to see if the barrel moves up and down any at the ejection port, or if it is tight? If it doesn't move when you bear down on the end of the dowel, this is good. The back of the slide should be held forward with thumb pressure while you do this.
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I just did this test. There was no movement when I held the back of the slide forward with a little hand/thumb pressure. If I removed my hand and released the slight pressure on the back of the slide, the barrel would eventually start to wiggle up and down with the dowel.

As for the link measurement, that came out to be .278".

I should be taking video clips of this stuff (my sweet Nikon does that too!). My inexperience doesn't help diagnose the troubleshooting :o

BTW, I just did a mark up on the slide lugs and barrel lug contact, assembled slide, barrel, bushing and slide stop....

...with link (sorry about the flash):
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...without link:
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Shorts,

It looks like you're in good shape. When I saw the back of the slide ever so slightly forward of the back of the frame, I was worried you had run out of material before lug cutting could begin, but Dave's observation that you had plenty of meat was correct. You don't need any lug cutting, however, since you are already slide-forward and locked up. The only improvement possible would be to check for unevenness in the lug contacts against the assembly pin. Hallock covered this (page169 in my copy). (While you're at it, re-read pages 124-130 for link details.)

Assuming feet to be even, just check that the existing link lets your slide get to the exact same position and the barrel just as high up in the ejector port as it went without the link. If so, you are in like flint.

We'll have to get you to buy a tube of Prussian blue (Hi Spot blue). This is a blue dye in a grease base. Because it doesn't dry, it has the advantage of thinning where contact is good. This lets you see grades of contract rather than the on/off go/no-go nature of layout blue or Magic Marker. Also gets thinner than the dry film coloring. Better for scraping.

I made a pull-scraper some years ago from water hardening drill rod. It is easier to scrape lugs with. I will see if I can detail it this evening. Day job is calling now.

Nick
 
I spent the better part of today on and off with the slide and link. I'm still not getting a good lockup. My numbers are running about .055-.056". Lockup with link and w/o, there is a different of .018"-.020". That's a lot :mad: I have no contact areas stopping movement in the barrel or slide lugs.

With both link and w/o, I did the flash hole test (empty brass with primer pocket drilled out at center) and the firing pin hole alignment was very close on both, all be it, about dead on w/o the link, and I could just barely make out an edge with the link.

Ok, I've gotta go do a workout to calm my nerves :o
 
This seems to going better than I had hoped with Bob and Nick's help we are marching through Georgia. Shorts seems to ba able to handle a file and sanding sicks quite well and that is a blessing.

It looks like the slide and frame are lined up pretty good. Bear in mind that a 1/16th of an inch either way can be cleaned up later. On Custom Guns, nothing fits at the start, but it will all come together at some point in time.

I wish I could help you understand Lock Up better. Imagine this: The barrel is in postion and is held in place by the link and pin on the bottom with the slide stop, and is locked in place above this by the two barrel lugs engaging the grooves in the slide. The lower lugs are resting on the slide stop pin with the link in between them. If the barrel lugs are tight against these lower lugs, that is a plus, but it does not have to be perfect there. The grooves in the slide have space above them all of the time. They have very little space when the gun is locked up in battery, and when the gun is fired, the link pulls the slide down and the barrel is out of those grooves until the slide picks up a round, stuffs it in the chamber, and the slide enagages the barrel lugs as the slide stop pin forces the barrel up in the slide again.

What is going to be important here is how tight we can get that barrel to sit there in lock up on the lower lugs. Anything over .050 up in the grooves is fine. We check the fit by pushing down on the barrel hood. If it is a solid feel when you do that , the gun will be accurate.

The magic number on the little gap between the feed ramp and the barrel throat is 1/32 on an inch. This is a must for feeding reliabliity as the round must be pushed out of the magazine, smack the feed ramp and then bump up into the chamber where it hits the top of the chamber and then is guided into the firing postion.

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Note the gap between the feed ramp and the barrel throat. This feeds great because it is a bottle neck round, but it is the same gap for any 1911. This is the best picture I could find right away.

Amatuers ruin feed ramps on a regular basis because they think that this should be a smooth transition between the feed ramp and barrel throat. That is why we had to weld up the feed ramp on the '70 series Colt so we could re cut it and have the little gap back. That gun has been fired with a wide variety of ammo and runs 100 % so far.

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We restored this one to it's former splendor after some "five thumbed clutz" ruined it. It was butt ugly when it showed up here and left a neat looking shooter of the flat black variety that we like. It took a lot of work but the owner felt it was worth it. Since he is a close personal friend, I undertook the job.

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I am sure you know how I hate to return these guns. I really get to like them.
 
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