Order of Fit: slide, frame, barrel & bushing

[Shorts]

I'm not sure we're helping Shorts with all this foolishness,

lol Shorts is just going on with her business, you guys are now background noise to my work

[Dave Sample]

Metric gun with CMC parts installed. Very Interesting to me. But what do I know?
Handy: I think that MIM is a very poor choice of metal for a hammer strut. On the other hand, I don't know what an Ed Brown hmmer strut is made of. All I know is that they work fine for me and have worked fine for a good many years. I have not been happy with anything else. I have never had one break but we work them over and install them with compatable parts. I teach my students to install a hammer strut and do not view them as "Drop In's". If done incorrectly they can hit the back of the beavertail and cause a twang noise everytime the hammer is dropped. We had a Colorado smith that was famous for this.

Less you don't understand, Pistolsmithing is a highly skilled occupation and in my opinion, takes years to learn.

We are helping Shorts because I like her Spirit and her trying to do something neat for herself. I like to help others if they want my help and until she tells me to get lost, I will be on her team. You can take that to the bank! She has undertaken a project that I would never even try , but I will try to help her anyway I can with the small details here and there. It is my pleasure, Sirs amd Madames.

[Bill Z]

Well, it breaking in the middle would fit my theory. Sometimes the geometry between the parts will be bad and the strut will hit in the MSH or as Dave says the grip safety. I can see where tis could add stress to the part, especially during a recoil cycle while being fired, and causing the break. The material it is made out of wouldn't matter much here I don't think.

I always invisioned one breaking at what I would consider the weakest point, the ring at top. I have serrated these in the past, removing material from here, and have never had one break, so it is interesting to me that one wouild break at the thickest portion. That is also the general area you would get the impact or rub though.

Now, splain me the wearing out of the hammer and sear. What wore out? Were they altered? Were they checked for even contact when they were installed? Was it even wear or one side ot the other? The MIM is normally very hard, so I find this curious also.

[Hunter Customs]

First I want to apologize to Shorts as I do believe this thread has drifted off topic. That being said seeing that my name is being thrown around with things some seem to think I said I feel I must respond to this.

Dave and Dean,
Not once did I name CMC parts when I made reference to MIM parts. If you go back and read what I said I'm sure you will see this. As a professional I do not come to a public forum and bad mouth manufactures or other smiths as some seem to take pride in doing on this forum. By the way Dave MIM is not the type of steel but the process in which the part is made.

Dean,
You ask what parts I use, I believe I can see where this is going. However just in case you are sincere I've used several different manufactures parts over the years again being a professional it will serve no purpose to post their names. I will say that some parts were cast some were barstock some were forged all have served me well. Brownell's (not name dropping Bill just fact) does a pretty good job of listing the manufacture process of the parts they sell. However if it's not listed contact the manufacture of the part you are interested in I believe most will tell you the process in which the part was made.
Seeing that you are a student of metallurgy I do believe what would better serve Shorts or anyone thats reading this thread is if you would explain the difference between ways to manufacture parts such as, die casting, investment casting, drop forging, and hammer forging. If you would be so kind to do this I'm sure they would have a better understanding of the MIM debate and see why you believe it's structually surperior or even as good as the other processes in manufacturing parts.

To all that may be concerned,
It's plain to see that Dean, Dave, and Bill prefer to use and endorse using MIM parts when building their guns. I have no bones with this as that is their business.
My business is to give my customers the best value for their dollars spent without handing them a substandard gun.
Here's a little food for thought. If MIM is such a great process in manufacturing parts I wonder why the major players in the industry are not using it to manufacture barrels, slides, and frames? Barrels, slides, and frames have been made from the process of casting and forging.

Regards
Bob Hunter
www.huntercustoms.com

[Bill Z]

Well Bob, if you read my posts, I did say I used different parts and am trying different parts.The CMC parts that we spoke about are what we use for our first time builders, exactly what Shorts is doing. I know, the Devil's in the details and everything needs reading. There is even a very clear and consise reason for using those parts given. Sorry that was lost on you.

Now, the use of MIM is not practical for all applications. It seems to work well in the automotive industry in making crankshafts but not in engine blocks. Your reasoning as to feel it is not suitable for use in some parts of a pistol because you shouldn't make a barrel out of it isn't really a fair comparison. For your comparison to be valid, any polymer gun would self destruct immediatly. Any lightweight alloy or aluminum gun would just self destruct. I've got a Glock on my bench for replacement sights I know has several thousand rounds through it and doesn't look the worse for wear and a Kimber TLE with over 20,000 rounds through it that's not even battered or loose, just dirty as hell since the shooter felt like a boresnake and some gunscrubber was adequate to clean the pistol. While it's a great testimony to the design, it atarted to have a few issues that have been readily resolved. (BTW, didn't have to replace the first part on this pistol, save for the springs, which are not MIM ) We did do some really cool sights on it though.

[Shorts]

Well, I've read a while back the difference in forging, casting, MIM and stamped. My take on the MIM parts is that quality in the production process will yield quality in the perfomance. While MIM is easier to 'screw up' and make the part weak right off the bat, when done right, it should perform well.

[Hunter Customs]

Bill,
Does your plastic gun have plastic rails? Have you ever seen a Aluminum frame fail? I have, it's a well known fact that aluminum frame guns are great for carry but it always seems the concensus is to not shoot an aluminum frame gun a lot. This holds especially true with high pressure loads such as plus P loads. For general information there is an alloy on the market that's as light as T6 but twice as strong and is as easy to machine as T6 but that's another story. Anyone who does not think the hammer in a 1911 style pistol is a high stress part might want to take another look at the hammer and what happens when the gun is fired. I've seen and replaced MIM hammers with the hooks sheared off, I don't find this to be a good thing.
I also don't find 20,000 rounds as that much of a test. When the test gun gets past 100,000 rounds of ammo that's making a 210 plus power factor (no powder puff loads) and about 200,000 dry firings let me know.
Regards
Bob Hunter
www.huntercustoms.com

[Dave Sample]

All pistolsmiths have their own opinion about parts. To imply that I do not know what the MIM Process is interesting since I have posted that process of taking metal and plastic in a very fine mixture and the amount of each strictly measured, getting it really hot, and then injecting into molds, letting it cool popping it out, and then machining it, is kind of silly. Bob does not have any idea of what I know or don't know, but I can assure you that if I didn't know, I would not say anything.

Shorts is a first time builder by anyone's standards. She has not indicated to me that she has built a bunch of other guns so I am trying to help her get her First Project done to HER satisfaction, not mine. I am a 45ACP Man and She is a 9mm Woman. So be it. I have built 9mm's in a 1911 configuration and have built 9mm Majors for IPSC Shooters. I have also built a couple of .40 S&W's but will not longer waste my time with that caliber which I deem a poor choice for high end 1911 work. I like the.401 bullet size in my 400 Cor Bon, but that is a fun thing with me and is a Toy Gun. I don't pretend that it is anything else. It will never be for sale and will go to my son who likes wildcats like I do. I really wish some days that I still had the 10mm Centaur instead of that beautiful diamond ring, but a trade is a trade and we cannot snivel and whine about getting $4000.00 worth of diamonds for a shooter. I had converted it to 400 Cor Bon before I traded it.

I have to apologize for wandering off topic and it is not intentional. I am an old man now and love to ramble on about nonsense that is not pertainent to the subject.

Shorts! You go Girl!

[Bill Z]

Well, gee Bob, I never said that the hammer wasn't high stress, but is it high stress at the hooks or at the strut hole and hammer face and neck? Consider the hole on a hammer strut. Jammer had a strut break, but not at the hammer pin hole. I serrate these on occasion to 'sign' my work depleting the material by about 30%. Still never had one break.

You've never seen a forged hammer break? I have. I've also seen a forged frame break. This is all a matter of semantic's I think. Hell, these use MIM on internal parts of an engine that will see more cycles in a week than any gun will ever see in a lifetime. MIM may not be great stuff, but it sure ain't bad stuff. Cast parts can be victim to the same problems MIM can be, and heat treating can be bad on any parts. Ask Novak about there adjusting screws on the forst batch of Combat adjustables they sent out. They got screwed by there heat treater and had sight adjusting screws breaking. (BTW, they made good on every one and solved the problem. It's a great sight that I'm working with right now on a big project and like the sight.)

I have ntohing against forged or tool steel parts, I use them regularly. I also have a great deal of experience with the proper parts selection for first time builders that are learning over the internet, and what works for them. I would dare say that I am amoung the few that have the most experience doing this. Shorts is a first time builder and it was mearly suggested to her to use these parts. They work very, very, well. Hell, Kimber puts them in 50,000 guns a year, more than you and I and Dave and any dozen one or two man shops will ever build in a lifetime combined. I'd say for the failure rate, that's a pretty good test. Of course, I haven't seen a Kimber hammer or sear fail, and have only heard of a few, but no more than Colt or SA or anyone else.

Bob, I wish you continued success in your endeavors, you have great business practices and I like a fellow that sticks by his guns, but do you really think that it is better for a first time builder to play with a hundred dollar trigger group without the benefit of proper training that really has to be done first hand?

[AZta2guy]

You go shorts!!!! you are my new hero!!!!!!!!!!!!!!!!

Aim straight and have fun
Jon

[Shorts]

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

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.





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!

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

[Unclenick]

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

[Jammer Six]

Oooh, UncleNick, we are now friends!

Thank you!

[Shorts]

Great pdf UncleNick. That's just what I needed. I'm getting tired of looking at my unlocked bushing ....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.

[Unclenick]

Shorts,

BUMMER!

Nick

[Hunter Customs]

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

[Handy]

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.

[Shorts]

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?".

[Unclenick]

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

[Dave Sample]

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!

[Shorts]

WE are going to finish this Job come Hell or High Water

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

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

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)




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.




So it is all broken for good??

[Dave Sample]

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!

[Shorts]

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.



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??



hehehehehe my Brownell's order just got here 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!

[tex_n_cal]

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.



Kindly quit laughing at my dremel work 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.



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.

[Unclenick]

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