Attention Norinco Fans

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Lower Lug

I've gotten a report on two that did need light fitting after bringing the frame rails down. The guy said that he had to take a light cut...no more than a finishing cut...after the pads had been fitted to center the barrel in the slide
after the swaging operation. (I even ran into that once using a new in paper
GI barrel during a salvage/rebuild on an old Ithaca.) He's into restoring worn-out old warhorses like I do...so I figure that there's probably at least an even chance that's what I'll run into since that's going to be part of the rebuild. I rarely work with new frames and slides, so sometimes things gotta be juggled
to make'em work.
 
I've gotten a report on two that did need light fitting after bringing the frame rails down.
Click to expand...

If that be the case, go for a gunsmith fit barrel. The only reason he would have to cut the lugs is to bring the center hit on the FP down since swaging the rails doesn't affect the lower demensions, i.e..SS pin, which everything else is measured against and barrel bed/vertical impact surface. If there was a lot necessary to locate the FP hit, then more than a 'finishing' cut, whatever measurement that might be, would be necessary, and this would ruin the whole concept/system the barrel was designed for. He would have had to change the link also. The better option would have been a GS fit with the proper link determined after the lugs were cut. Now, some smiths, two I know of in particular, do put 'pins' in the lugs to create the same effect as the pads, but that's not a real mainstream method and one I wouldn't use or reccomend.

Now, using the Easy Fit with the pads would really preclude having to swage the rails down anyways. Sure, the frame and slide might have a little play, but when this system is in battery you have the pads fitted putting a solid lock between the two points in the top of the slide and the one point at the lugs. 95% of your accuracy in slide mounted sights is the barrel and slide fit, and this system carries it a little further. A gun that's so loose a great deal of swaging is necessary wouldn't be a good candidate for frame mounted optic's, not out of my shop anyway's.
 
EZ Fit System

Roger that Bill...I understand the concept behind the system, but the guy told me that after the swage-down...and after he got the firing pin centered,
that the vertical stacking put the lower lug into a light bind with the crosspin
ane kept the gun from going to battery by a tiny amount.

Match-type fits generally require light thumb pressure to push the slide the last bit...and is considered to be a good fit...but he said that it was tighter than that...and he wasn't after a full match fit anyway...so he relieved the
lower lug a little from where the tight spot started all the way into battery.

The interference wasn't much, and he didn't use a lug cutter. The adjustment was obtained with a 3/16ths drill rod and 600-grit lapping compound with the slide under a load from the recoil spring...turned by hand. The link required a little massaging to get the crosspin back into contact with the lugs so that the barrel wouldn't stand on it in vertical lockup, and to regain full contact across both sides of the lug and the link.

The disconnect slot in the slide also had to be deepened slightly due to the lowering of the rails and slide. Such things are pretty commonplace when
salvaging worn frames and slides. Makes a different approach sometimes necessary when not starting from scratch with new, in-spec frames and slides. Such are the headaches that I've had to deal with, since I usually work with old USGI and well-worn commercial Colts, etc. Each one becomes a law unto itself.

He also said that one gun required a little work at the barrel bed in the frame bridge to let the barrel fall low enough to allow the slide to pass over the top without hitting the locking lugs. Another operation that I've had to do on occasion, sometimes requiring so much that I took part from the lower radius of the barrel and part from the frame.

I ran into much the same situation last year when I tightened up the slide to frame fit on a nearly new NRM Colt Government Model with the factory barrel. It removed all the vertical play at the rear of the barrel and since the link was the correct length, no adjustment was needed on that. A fitted bushing capped it off, and the accuracy was improved quite a bit.

I fully intend to give the Kart EZ-Fit a try on a future project...Already
got it in the planning stages...and I'll do a report on it when it's finished.
 
I work with old stuff too John, we all do. He would have been better off polishing the hood of that barrel down a little instead of altering the lugs and the barrel bed. The hoods on these barrels don't come polished anyways, and even on a new frame and slide it is necessary to polish the hoods all the way around. This would have kept the lower in spec and the barrel in spec and sounds like it would have had just the slightest off center hit which really isn't that big of a deal. I guess it's six of one and half dozen of the other, but I'm betting that his hood is still in the rough like it was sent from Shallotte, NC in the first place.

The point I'm trying to make is that the barrel is designed from the lower lugs up. The lower lugs carry the load at the top radius and lower tip of the lugs with a free space in the arc of the lugs. This gives a wedge lock on the pin that is always repeatable. Lapping this area in too much or altering the link will give the barrel an opportunity to lock up anywhere in the arc and at varying degrees. Now we are only talking thousanths here, but that relates to half an inch at 50 yards, per .001 of difference, of mechanical accuracy this one action alone eliminated, or possibly eliminated. How many times have we both agreed that .001 is the difference between right and wrong in a lot of instances, or that it looks like a mile long?

If all of the alterations your buddy had to make were necessary for everything to work he could have saved about 50.00 on the barrel and another 40.00 on the installation kit and went with a gunsmith fit barrel. If he would have left them alone and just polished the hood down that 'finishing cut' amount instead of altering the frame, lugs and link, he would have recieved the full potential out of the barrel and not taken a chance of altering the linkdown timing by putting an eccentric round on the link, besides, it would have been a lot easier to do a little shoe shining then all of the hassel he went through. Actually, depending on the amount of play, he could have avoided the entire swaging process that will eventually loosen up anyways.
 
Fittem Up

Bill Z said:

>but I'm betting that his hood is still in the rough like it was sent from Shallotte, NC in the first place.<
**********************

Howdy Bill...You'd lose that bet. This wasn't exactly his first trip to the county fair. :p

I understand perfectly what you're saying. He'd much prefer to work with a
"Hard Fit" barrel too...but he got a deal on the pair and had a project in the works for his two grandsons, and figured "What the hell." I spent nearly an hour on the phone with him...on my dime...listening to him describe the
virtues of the Kart system as opposed to the virtues of the Scheumann
hard-fit barrels. He likes the system, but says that it does have a few drawbacks when working with worn, salvaged pistols.

Getting the firing pin hit centered is a big deal for him, and once that was done...the only option that he had open was to go to the lower lug, since he had already gone to a .195 diameter slidestop pin. He wouldn't remove any more of the hood and tops of the locking lugs than necessary to clean'em up
because he believes in as much veritcal lug engagement as he can get, especially on that first lug at the front of the hood. So do I, because that's the main one. Unless a full hard fit barrel is used...complete with oversized hood and short, semi-finished chamber...often the two forward lugs don't hit at all, and cutting back on the first lug sometimes still only allows for one more, and increases headspace by the amount of adjustment on the first lug.
Once in a while, you get lucky and get them to equalize...but with a low-pressure round like the .45 ACP, it's not really that critical for the lugs to equalize.

Anyway...He only ran into the problem with one of the pistols. The other one worked out just fine. It was just a matter of how the tolerances stacked up
after the swage-down. Like I said...I'm gonna try one of the Kart barrels for an upcoming project. I'll know more about how it works at that time.

Meanwhile..I've got a third Norinco (with a BAD headspace problem) on the bench and two more Springfield barrels on the way. I'll check both and see how things look when they come in. Hopefully, I'll have another half-dozen pistols lined up to check against the barrels byt then too...This does look promising for those who have Norks with sloppy barrel fit or bad headspace and don't want to go the full route to upgrade their guns and make them safe
and happy.

Stand by...More info on the way.
 
I understand perfectly what you're saying. He'd much prefer to work with a
"Hard Fit" barrel too...but he got a deal on the pair and had a project in the works for his two grandsons, and figured "What the hell."
Click to expand...

The Kart Easy Fit is hard fit, more so than a gunsmith fit and for the little you are talking he removed, it would be impercievable on the FP hit and polishing the hood a little more would have cured the woes, unless of course he took more off of the lugs than he is admitting too. I still wouldn'y cut an eccentric in the link either way, and then replacing it is just like installing a GS fit, but then he would need the correct link, if he knew how to determine it, so that was just extra value/money spent/wasted. His dollars, not mine.

Both of you are missing the entire point of the Kart system. I'm sure you will be enlightened when you finally get around to ordering one and reading the manual, I seem not be able to get my point across, but I blame that on Fred calling it an Easy Fit and not coming up with a better name for it, but I cannot think of one either, oh well. Hopefully the preconcieved perceptions of this barrel will disappear in time and people will understand it's function before they keep assuming what it is. BTW, the quality and materials of the barrels is the same, they are both NM barrels, it's the lock-up and fitting part that is different and the bushing is correct for the barrel to boot. You'll see.
 
Drop in?

So these barrels would be considered true drop in for SA production models?
I have one 1911 and is my only handgun so I plan to get a few spare parts. One barrel and one extractor and so forth.
I would get those parts from SA that would fit drop in and fix all that do not.
 
Drop-In for Springers?

txgho1911 asked:

>So these barrels would be considered true drop in for SA production
models?<<
*****************

Now that's the 64-dollar question. While a Springfield barrel...or one made to Springfield's set of specs...would afford the best CHANCE of a simple, drop-in fit, it's best not to count on it. Years ago, it was a government requirement
for the guns from all contractors to provide complete interchangeability of parts, but since the guns aren't destined for life and death in faraway places any more...there's really no such thing as the promise of a drop-in fit on anything.

The situation that I stumbled on with the Norincos may simply be a stroke of good fortune on those particular barrels and those particular guns...and they did require some light fitting. Both barrels that worked nicely in the two pistols also seemed to bear out in a third gun that I don't own. I've got two more on the way, and I plan to try them in a few Norincos that belong to
several friends...just to see if it was a fluke, or if it's a common occurence.
Time will tell.

I do know that those same barrels didn't have the overlength hood just three years ago...and that they did drop into a pair of old GI Colts and work
pretty well, though there was also a little fitting required...it was very little.
Headspace was well within spec for both guns, and they've both done hard range duty ever since, with over 30,000 rounds logged between the pair
before the slides cracked. I replaced them with Essex castings...with the same results as with the original slides. After fitting the Essex slides with new bushings, the barrels were drop-in and go. Another 20,000 or so rounds and they're still on the line...though they're starting to loosen up a bit.
 
Kart

Howdy P-32, and welcome aboard.

The more I hear about those barrels, the more anxious I am to try one. I'm
curious as to how readily the lugs will equalize horizontally, and how much finishing the chambers need...I'll probably have the opportunity to do one early this coming summer. Still waitin' for word to start.
 
Update

Update:

Two more barrels arrived the other day. They both checked out pretty closely to the same way that the first two did in the same two Norincos.
Two more pistols that were brought in for the check produced the same results. A fifth one didn't. There were a few issues with the slide dimensions that required more work to get one of the barrels installed
correctly, and I could only get two of the lugs to engage horizontally
after setting the load-bearing face of the first lug back .005 inch and
firing the gun 50 times. The lug locations on all 4 barrels were within
.002 inch of each other...so the issue was in the slide itself. In all others,
the lugs equalized nicely.

Vertical lockup produced a lot of interference in that one gun...much more than in any of the others...requiring more material removal in the slots
between the barrel lugs. Once the barrel centered in the slide, a little
scraping and lapping of the lower lug was needed to relieve the remaining
tightness. in vertical lockup.

This pistol also required .003 inch of reduction on the bottom radius of the barrel behind the lug in order to obtain correct linkdown clearance with the slide...and to keep the barrel from stopping hard on the frame bridge and stretching the link, I removed an additional small amount from the frame bridge itself. Also, the #1 lug required light dressing in order to obtain clearance for the slide. There was no hard contact with the corner, but
there was light contact along the top of the lug. Likely would have worn in
with use, but it was dressed lightly with a smooth mill file and polished
with emery cloth via the "Shoe Shine" method anyway.

Total headspace for the barrel in this particular gun is a bit more than I like, but still within acceptable ordnance specs at .008 inch above minimum as measured with a GO gauge and feeler gauges...for a total
breechface to stop shoulder dimension of .906 inch, with .002 inch
clearance between the slide and hood as measured with shim stock.
I expect that additional firing will allow a little more horizontal equalization between the #1 and 2 lugs, which may allow light contact on #3. This will
likely produce a total hood to slide clearance of around .005 inch, which is
also acceptable in an ordnance-spec, service grade pistol, and MUCH better than the OEM barrel fit...which had excessive headspace and unacceptable fore/aft play within the slide.

So far...the Springfield/Norinco match seems to stand at an 80% chance of a quick and easy upgrade. I'll know more as more pistols come in for
examination. 4 of the owners contacted have ordered the barrels for the upgrade on their guns, which will provide more in-depth information as they are installed and fitted.

On an additional note...The barrels come from Springfield with slightly raised material in the slots between the lugs. The slots, rather than being machined flat and square with the lugs, are slightly raised in the middle,
which seems to work a little like the Kart EZ-Fit system. Not sure whether this is intentional and specifically FOR that purpose, or if it was the result of the EDM machining process...but it works well. Note that the Hammer Squaring file with two safe sides from Brownells fits between the slots, and is perfect for the job. The safe sides allow the slots to be cut deeper without removing material from the lug faces, and vice versa.

That's all for now. I'll report more as I learn more.
 
Hello,
Any updates as to the Norinco/Springfield barrel replacement? I am considering such an upgrade in my own Norinco rather than invest in a match barrel. Do the vast majority of Norincos have the headspace/locking lug issues or is it hit and miss with them?
Thanks!
 
Nork

Howdy MNine,

The Norinco barrel issues seem to be fairly hit and miss, but not rare by any stretch. Near as I can determine...about 1 in 10 could stand a new barrel.

The Springfield service barrels worked out nicely, but weren't drop-in. They needed light fitting in the Norincos that I used'em in. The Kart EZ-Fit would have been better overall, but the Springer tubes were almost 50 bucks a copy cheaper, and yielded completely satisfactory results with complete
feed reliability with little tweakin' involved, and accuracy on a par with the average Gold Cup. Not match-grade, but good enough to bounce oil cans at 50 yards if I don't drink that third cuppa Turbocoffee before headin' for the range. :rolleyes:

My goal wasn't accuracy so much as it was a slop-free fit and a little tighter headspace. The ones that were OEM were very close to SAAMI maximum
at .918 inch...well past my self-imposed max of .910 for a hard-use shooter...
so I decided to rebarrel the guns and put'em to work.
 
Johnny, after you get sorted out with your move, I'd like to get with you to give my Nork a checkover as well as the Colt Commemorative. Just looking at the barrel lugs on top of the Colt, the rear one is shiny and the front one still blued. Dont't think the load is evened out the way it should. Also, it tosses some cases in my face. And I have a set of sights for the Nork I'd like to get put on.

Hope you arn't moving in this rain we're getting.

Ted/Lexington area
 
Ted's Pistols

Howdy Ted,

Since I'll be about 20 minutes away, I'll be happy to check'em out...but the dovetailing of sights is probably a lost cause, since lightening ran in on my mill and killed it deader'n a stone a couple years back. I don't forsee any relief in the near future, since I've dropped over 200 grand on this new house, and I flat ain't got the bucks to ante up for another one. Oh well...At least I ain't gotta make house payments... :cool:

I dontated the old one to the local trade school to give the lads in the electrical classes a challenge...and it wound up in the machine shop. I go visit it every so often. :rolleyes:

My lathe, however is still good...though I'm gonna hafta replace the split nut
and the lead screw before too much longer. I hope to get around to that sometime this summer.
 
Johnny, hoping the sights will fit the Nork pretty well. Got them from Brownell's with rear dovetail supposed to fit "Colt " with front being a narrow tenon...which I think is what the Nork is.

Give me a shout, or email when you have the time...and directions to your new place.
 
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