Broken Norinco 1911 slide release

[Homer]

Norinco 1911 all stock with 2500 round count:

Today the slide release broke in the pin area that slides thru the frame and barrel link. Two thirds of the pin broke off and fell out of the frame while firing. I have two questions:

1. Besides just plain being a defective part, is there any other reason that would have caused this?

2. Will a replacement slide release require fitting or will most drop in?

Homer

 

[HSMITH]

Homer, although it is possible that it was just a bad part it is also possible that there is something with the barrel fitting and/or timing that needs to be fixed If you don't know what it takes to fit and time a barrel 1911Tuner has posted a goldmine of info, a search on his username and a night of reading is well worth it. You need a new slide stop, that is not in question. Get it and check out the gun to make sure that is all you need.

 

[Homer]

HSMITH

Thanks for reply and info...

 

[1911Tuner]

Broke

Look at the link to see if it appears to be stretched or with an oblong slidestop pin hole.

 

[Homer]

1911 Tuner

Link does not appear to be stretched nor did the slidestop pin hole appear to be oblong. I did pull the link and check the slidestop pin hole. It measures .205 from front to back and .206 from top to bottom...

As HSMITH suggested, I did some further reading. I found ur bit on stem binds. I have been expriencing stem binds. I thought it was a combination of bullet selection and mags. Bought some Metalforms 7 round roundtops. Did not seem to help stem binds and might have been slightly worse than the factory mags. Approx. stem bind percentages as follows:

Ball rounds almost none.
H&G 68 200 gr SWC 1% or less.
RCBS 82045 200 gr SWC (short nose & 2 lube grooves) 15%. As I was given 12,000 of these bullets, I hoping to get the gun to run with these.

I checked the top of the throat and the edge appears to be eased/radiused well. I could not see a noticable gap at the link/front radius area.

Could the stem binds and broken slide release be related?

A buddy of mine gave me a used slide release. It seems to work without modification. He gave me a new Wilson #2 link he had. The package states it is a .273 not .275 as u stated in ur other thread.

I plan to try the fit of the shorter link unless you feel this would be too short...

Thanks for the reply and insights.

Homer

 

[1911Tuner]

#2 Link

Given the average Norinco's specs, I'll say that the .273 link will be short.
The problem with too-short links is that they tend to advance the start of the unlock sequence...which if it occurs while there's still pressure in the bore, can damage the lugs, link, and lower barrel lug. Also the distinct possibility that it won't draw the barrel far enough down to prevent the locking lugs from crashing with those in the slide...shearing the top corners of the lugs.

I doubt if the barrel riding the link around the forward radius of the lower lug would have broken the slidestop pin, though it could contribute to the excessive stem bind. Very few Norincos have feed/return to battery issues, and I'd be more inclined to think that yours is being caused by excessive extractor tension and/or a canked extractor channel or breechface guide wall width...too narrow....or a burr or rough machine mark on the breechface itself.

If you use the #2 link, flip the gun upside down and hand-cycle it to see if it works smoothly. Any sign of a hitch in the cycle indicates that the barrel isn't unlocking. Also a possibility that the link will be too short to allow the bottom of the lug to pass over the slidestop pin...stopping it from going to battery even when empty.

See if the gun will return to battery more smoothly with the extractor removed. If there's no change, try it without the link. You may be able to narrow it down to one or the other. If neither one makes a difference, you'll need to look at other things.

 

[Dean Taylor]

I do not know what stem binding is. I can find no parts list or parts diagram for a 1911 or a 1911 magazine that lists a "stem" as a part. Please identify this part for me. I have seen barrel link binding due to the link, the link pin and also the slide stop.

I am not a Noriunco 1911 expert like 1911 Tuner but I have fitted a new #3 barrel link (.278) in mine along with a new barrel link pin and slide stop. I have seen a #2 link (short link) used when the barrel throat/bed is screwed up but have not seen it work reliabily. I do not understand why you want to use the short link.

If the slide stop fit is sloppy I would consider fitting an over size slide stop.

I would bet you got a bad part. Norincos are usually made of good hard steel.

Dean
[email protected]
410-952-7848

 

[1911Tuner]

Stem Bind

I do not know what stem binding is. I can find no parts list or parts diagram for a 1911 or a 1911 magazine that lists a "stem" as a part. Please identify this part for me. I have seen barrel link binding due to the link, the link pin and also the slide stop.
Dean
[email protected]
410-952-7848

Stem bind...aka 3-point jam. Actually a misnomer, since all Browning tilting barrel designs essentially operate with a little stem bind. Excessive stem bind
is correctly called the 3-point jam which causes most failures to go to/return to battery.

And now ya know...

 

[1911Tuner]

Norks

For all the Norinco lovers...I'm particularly fond of the Pimpgun...Hard-chromed by Tripp with a hard-fit Kart barrel. Good shooter and gobbles everything I can throw at her. One-piece milled (early) Colt trigger installed makes it a real sweetie.

And you thought there weren't more than five Norks in the whole state...

 

[Homer]

#2 Link

1911 Tuner

I have installed the #2 link. I cycled the gun by hand upside down with both links. Could not tell a difference between the two and no hitchs were felt or seen with #2 installed. I hand cycled some loaded rounds. Feels smoother with the #2. Dropping the slide on a loaded mag with the old link, I could feel a slight hesitation in the silde at about a half an inch from full battery. Seems a lot crisper with #2 and no hesitation...Could be my imagination tho.

I am not sure how to check for excessive extrator tension.

I have no clue what a canked extractor channel is...

Could you please advise on both.

Breech face shows light machine marks but feels smooth.

Breech face guide width is .492.

Thanks

Homer

 

[1911Tuner]

re:

Sounds like the link was contrbuting to the stem bind condition....or possibly it was an out-of-spec lower barrel lug.

Remove the extractor and clean the channel completely. Pipe cleaners and solvent will help. While the extractor is out, hand-cycle a few more rounds through the gun to see if it's better. You'll have to invert the gun and shake the rounds out...no extractor to pull'em.

Extractor in...let a round chamber at full speed. If you're using live ammo, be VERY careful. Draw the slide rearward slowly, just far enough to pull the round out of the chamber, but don't let it touch the ejector. Magazine out for this. The round should sag slightly, but not fall off the slide when shaken lightly. If it doesn't sag a bit, there's too much tension. If it falls through the magwell, there's not enough.

Now to the short link. The unlock sequence should just begin at about .100-.110 inch of slide travel. Without a dial indicator, it'll be hard to determine exactly when it starts, so fire the gun a few times and check the top corners of the locking lugs for any sign of rounding or peening.

Check this too:

With the slidestop pin through the frame and link, but with the arm hanging vertically and the recoil spring plug removed to free the spring...push the slide fully rearward and hold it. Push the barrel fully rearward and down firmly
while moving the slidestop arm. It should swing feely with no binding. A very slight amount of tightness is probably okay...but so tight that you can't move the arm with a light flick of your fingernail is too much and indicates that the barrel's rearward movement is being stopped by the link instead of the vertical impact surface in the frame. This can result in another broken pin or a stretched/broken link fairly early...within about 500 rounds or so.

This is why I asked about any stretching of the link, and indicates that you may have a linkdown timing problem due to the vertical impact surface located too far rearward...or the lower barrel lug located too far forward.
This condition puts stresses on the link and slidestop pin that they weren't designed to bear, and will cause a failure in one or the other sooner or later, depending on how far out of spec these areas are. In extreme cases, it can cause the lower barrel lug to separate from the barrel...or even crack the chamber floor.

 

[Homer]

Tuner

I always remove extractor and clean the channel with each cleaning. Checked cycle of rounds w/o extractor. No differrence.

Chambered round and checked extractor tension. Checks good per ur instructions.

Fired 140 rounds today with shorter link. No signs of peening.

With the slidestop pin through the frame and link, but with the arm hanging vertically and the recoil spring plug removed to free the spring...push the slide fully rearward and hold it. Push the barrel fully rearward and down firmly
while moving the slidestop arm. It should swing feely with no binding. A very slight amount of tightness is probably okay...but so tight that you can't move the arm with a light flick of your fingernail is too much and indicates that the barrel's rearward movement is being stopped by the link instead of the vertical impact surface in the frame. This can result in another broken pin or a stretched/broken link fairly early...within about 500 rounds or so.

I checked this last night. I did not feel any friction while manipulating the barrel by hand. Could get some binding by placing 6 o'clock position of muzzle on workbench and pushing down. A little excessive tho I think....

Now about today....I am still getting a stem binds. The slide stops about 3/8 to 1/2 of an inch from battery. Rim of case has not quite made contact with extractor...
I quess the round might be hanging up on unseen roughness/defect on breechface. there is light vertical machine marks on the face. Your thoughts and suggestions on polishing same.

Again thanks for ur time and input.

Homer

 

[1911Tuner]

Stem Bind

Howdy Homer,

If the rim hadn't engaged the extractor yet...remove the extractor and measure the two small parallel rails on the underside of the slide. You want
.484-.488 inch between the rails.

If you can get the stoppage to occur by hand-cycling, lightly bump the muzzle with a foot-long piece of wood...just a tap...to see if the gun snaps to battery.

Quote:

>I checked this last night. I did not feel any friction while manipulating the barrel by hand. Could get some binding by placing 6 o'clock position of muzzle on workbench and pushing down. A little excessive tho I think.<
*********************

Look at how far back the barrel sits in the frame pushed all the way back with the slidestop pin installed. Remove the link and check again to see how much difference there is.

 

[Homer]

Tuner

Gap between rails is .492".

I got the stoppage to occur by hand-cycling but at a much reduced rate of about 7% vs. 15% live fire. Light rap on muzzle got it to go to battery every time. Just note: muzzle was a consistent 5/8" proud of the bushing on each stoppage.

Look at how far back the barrel sits in the frame pushed all the way back with the slidestop pin installed. Remove the link and check again to see how much difference there is.

No noticable difference.

Thanks...

Homer

 

[1911Tuner]

re:

Okay...Ruled out a problem with the link. The light binding isn't caused by stretching of the link. The 3-point jam/stem bind seems to be coming from the barrel either rising too early as the round tries to break over to horizontal...or the barrel itself isn't dropping completely into the bed.

Lay the barrel back into the frame and install the slidestop pin. Look to see if there's a fairly wide space between the bottom of the barrel and the top of the frame bed with the barrel pushed down and back.

Also check to see if the lower edge of the barrel throat is overhanging into the magwell. It should be sitting slightly forward of the top corner of the feed ramp...about a 32nd inch...but most Norincos that I've seen have that lower edge flush with the top of the ramp. Check for a sharp corner at the top of the barrel throat too. That can cause the side of the cartrdge case to snag and pull the barrel forward...which also tends to cause the barrel to rise early relative to the slide's position.

If all checks out okay, and the link isn't pivoting the barrel, there may be a problem with the geometry of the lower barrel lug, causing the barrel to rise too abruptly on the slidestop pin.

For Dean..who hasn't heard of stem bind and/or 3-point jam...Here's a brief description of what happens:

The cartridge enters the chamber at an angle, and drags on the top of the barrel throat at the corner. The barrel rises too early or too abruptly while the slide is pushing on the rear of the round, increasing the angle that the cartridge has to overcome in order to break over. The bullet ogive strikes the chamber roof, causing a bind at three points: On the side of the case, just below the mouth...At the bullet ogive...and at the breechface. Three points. Excessive extractor tension can contribute to the problem, but isn't a cause by itself.

The "Stem" is the cartridge itself that's in a bind at these three points. A telltale sign of a stem bind is a small, crescent-shaped mark about 1/8th inch long and about 1/8th inch below the case mouth. It can be a light mark...not much more than a scrape...or it can be fairly deep, like a small gouge and well-defined, depending on how hard the bind is. Some can actually deform the case. Most just leave a light mark. Breaking the corner at the top of the barrel throat doesn't usually cure a hard stem bind. It just "softens" the mark. Stem-binding related failure to got to battery is probably the single most frequent cause of
overthroating of barrels by amateurs who don't understand what the problem is.

Now, run tell that...

 

[HSMITH]

It ought to cost for such advise.

Thank you Johnny for helping the average soul, above and beyond come to mind...........

 

[1911Tuner]

re:

It ought to cost for such advise.

Thank you Johnny for helping the average soul, above and beyond come to mind...........

Many thanks for the good words, Mr. Smith. I appreciate it more than you know.

Another thought on the broken slidestop pin. If you haven't been in the habit of letting the slide go at full speed with the gun empty...and the new one also breaks...use a close-fitting drill rod in the frame holes to see if they're
drilled straight or at an angle. If the holes aren't straight, it puts a side-load on the pin, which can cause premature failure, especially if you drop the slide on empty very often. Pretty rare, but not unheard of, and could also contribute to your return to battery problems.

 

[Homer]

Tuner

Lay the barrel back into the frame and install the slidestop pin. Look to see if there's a fairly wide space between the bottom of the barrel and the top of the frame bed with the barrel pushed down and back.

My eyes are gettin" old but the fit is tight...002 gap at best. Pretty tight fit.

Also check to see if the lower edge of the barrel throat is overhanging into the magwell. It should be sitting slightly forward of the top corner of the feed ramp...about a 32nd inch...but most Norincos that I've seen have that lower edge flush with the top of the ramp. Check for a sharp corner at the top of the barrel throat too. That can cause the side of the cartrdge case to snag and pull the barrel forward...which also tends to cause the barrel to rise early relative to the slide's position.

Lower edge is not quite flush but pretty close... I'd say within .010. Definitely not overhanging. Top edge of throat appears to be eased nicely.

Thanks for hanging in...

Homer

 

[1911Tuner]

Hangin'

Mighty welcome, Homer.

Do one more little test. Lock the slide back and lock a mag into the well with one round in it. Lightly push the muzzle against a table edge and hand-cycle the round into battery. My bet is that it'll slide in like greased goose poop.
If it does, your barrel is rising too abruptly relative to the slide's position.

If you're using live ammo..use all due care.

 

[Homer]

Slight glitch

SSSLLLLLOOOOOWWW hand-cycle there is a slight hesitation and occasional hang-up as cartridge stops forward motion from mag. Moderate to fast cycling was slick.

I took the barrel and held it in place on the frame. Inserted mag with one round. Slide cartridge forward with finger and appears the meplat is is hanging on feed ramp. Ramp is reasonably smooth. Do not know if this has anything to do with it...

Also check to see if the lower edge of the barrel throat is overhanging into the magwell. It should be sitting slightly forward of the top corner of the feed ramp...about a 32nd inch...but most Norincos that I've seen have that lower edge flush with the top of the ramp. Check for a sharp corner at the top of the barrel throat too. That can cause the side of the cartrdge case to snag and pull the barrel forward...which also tends to cause the barrel to rise early relative to the slide's position.

I appear to have been mistaken on the throat overhang...there is slight overhang of the throat's lower edge into the magwell when barrel is pushed back and down on frame.. Not alot but enuf to catch my fingernail on. Many apologies for my oversight.....

Thanks

Homer

 

[1911Tuner]

Overhang

Eureka! We may have nailed the reason for your feed/return to battery problem.

The slight catch as the round moves forward in the mag is probably due to the raised dimple on the follower snagging the case rim. That means that it's doin' its job.

The standard fix for barrel overhang into the magwell is to file across the lower edge of the barrel throat at a slight angle to get the clearance, and reshaping the throat. Since Norinco barrels are hard-chromed, that presents a problem. A file won't cut it, and it'll have to be ground...along with the reshaping procedure. The other part of the problem is that...once the chrome plating has been breached, it will eventually start to peel and/or flake off. The good news is that the plating on the Norinco barrels is pretty good
and probably won't start to peel for a long time.

The problem is that the incoming round strikes the barrel throat (actually the barrel ramp) early and low instead of being deflected upward far enough by the corner of the frame ramp . The round drags on the barrel ramp, and pulls the barrel forward with it as it feeds instead of the slide initiating the barrel's forward movement at a later point...after the cartridge rim has gotten under the extractor and begun the breakover into the chamber. As the barrel moves forward, it also moves up. As it moves up, it increases the angle that the feeding round has to overcome in order to enter the chamber...and gets caught in the classic Three-Point Jam...aka "Stem Bind."

Your options are to LIGHTLY grind the lower edge of the barrel ramp to get it ahead of the frame ramp corner, and use a fine grinding stone in a Dremel to
LIGHTLY roll the flat edge that's left. (Can ya'll believe that I'm actually advising somebody to use a Dremel?)

If, on the other hand...the overhang is the result of somebody rounding the top corner of the frame ramp off...you've got a problem. Maybe salvagable if it's not too far gone...maybe not. If the frame has been altered beyond a certain point, it'll require machining and a steel insert like the ones that some shops install in alloy frames to prevent damage and wear. It's not a cheap fix.

 

[Homer]

Thanks

Tuner

Gun is stock, so I am hoping the frame ramp is in spec. Does not look like it's been altered.

As far me n Dremel...we don't mix. I got a neighbor that is a machinist/tool n die maker. I'll see if he thinks he's up to the challange.

Thanks for all the help and i'll let ya know how it turns out...

Just a side note...I measured the #2 link I put in after firing about 150 rounds. The slidestop pin hole might have stretched about .003. It measures .205 front to back .208. I did not measure before use.
Also, both links, #2 and original no measure the same from outsde to outside of both pin holes...
.456". Could be inconsequential.


Homer

 

[P-32]

I think we can go ahead and delete this one, since the poster's intent was to disrupt rather than to offer anything of value to the diagnosis
and repair.

 

[AnthonyRSS]

Now, I'm not a pistol smith, but I am a pretty active shooter. But it's still pretty clear to me that dog don't hunt.

But you don't know the Tuner.

Anthony

 

[1911Tuner]

re:

HOLD ON! Let me get this straight......A person is advising another to make a barrel ramp correction solely based on what the other said. We also have this problem called "Stem Bind" which is new lingo to me. The pistol has not been properly checked for other possible problems. Then we have a person telling the other to make the barrel ramp correction with no guidance on how to polish the chamber mouth with proper warnings. This a fine area which those with fat fingers can make the barrel unsafe very easily. There is no suggestion of using Go/No go gauges to see if there is room to make a ramp correction or limits on how much to safely go to start with. I understand this isn't rocket science, but I would hate to see the pistol dump hot gases down the mag well.

Now, I'm not a pistol smith, but I am a pretty active shooter. But it's still pretty clear to me that dog don't hunt.

Hi there P-32. Evidently you haven't read the whole thread on all that has been checked....and if you don't understand what stem bind/3-point jam is, do a search on the terms or take a basic gunsmithing course...before you jump in and start screamin' about huntin' dogs.

If the barrel throat is overhanging into the frame ramp, that has to be corrected first. Chances are that it will take care of the problem...but if it doesn't, we'll keep trying.

Lastly...I see by your username whence you come...and why.

Now then...If you'd like to offer something constructive in the diagnosis and/or correction of this problem that may have been overlooked, please feel free. If all you want to do is hijack the thread for your guru's entertainment and continued disruption of this forum...months after he was banned...please be gone.

Thank you for your cooperation in this matter.