Barrel Riding the Link -

[Sniper350]

I have been given a Colt Combat Commander that showed signs of feeding problems by evidence of Dremel damage to the barrel's feed ramp.

Closer inspection revealed that the owner had problems with the barrel link pin coming loose from the barrel as evidence of the peen marks on the pin as well as the lower lugs, in an attempt to secure the pin.

These are classic examples of a pistol that is "riding the barrel link" :
1. Feeding problems
2. Link pin hole oblonging

Lastly you can see where the lower lug radius is prestine -- no wear marks indicating the lower lug has been guided around the radius by the slide stop pin.

A close examination showed the barrel Link that was used is diffinately too long ........ this is a bit troublesome because there is still play on the barrel in verticle Lock-up. You can push the barrel down 1 mm when it is in lock up.

My question: If I replace the Barrel Link with the proper size for the lower lug cut .......... [ it will need a shorter Link ] will this not effect -negatively- the upper lug engagements. I am concerned that installing a shorter Link might hold the barrel down from reaching full lug engagement. Is this what will happen or do I have a wrong impression of the cause and effects here???? I understand the barrel Link is slightly passed verticle when the barrel is in full lock-up.


JF.

[Hunter]

The barrel bushing could be causing the barrel springing. A misfit bushing can allow vertical play.

[Sniper350]

Hunter - Thanks , I am sure that's part of the problem .

But how can I test to see if the barrel goes into verticle lock-up and stands on the slide pin stop as it is suppose to.

I have read that some production guns leave the factory with the barrel riding the barrel link through the radius - but they lock-out standing on the slide stop pin.

I am trying to figure out if the barrel link needs to be replaced in this particular pistol.

JF.

[Hunter]

I believe the test is it remove the slide stop from it's position against the plunger tube but leave it through the link and hanging down. Cycle the slide out of battery the slide stop should no bind (swing freely). If the slide stop is not swinging free out of battery the link is binding against it.
Remove the slide but leave the barrel in place. Hold the slide in your hand and using your thumb against the lower lug try to push the barrel up in the lugs. If the barrel springs in and out of the upper lugs that is a sign of the bushing binding the barrel causing it not to lock up properly.

[Iron bottom]

There are several things to look for. The lugs will seat on the pin at some point, to stop the slide. A shorter link may not let the lower lug contact the Vis correctly, and may reduce the barrel and slide lugs engagement below minimum. This is the way, going by your description, Colt fits barrels on the recent models I've seen. And they work fine and seem to be in spec. I don't think a shorter link will fit the lugs much better. I would suggest fitting a new aftermarket barrel. Feeding may involve the extractor, frame ramp, barrel ramp, breechface and magazines.

[Sniper350]

Thanks gentlemen -


This is the way, going by your description, Colt fits barrels on the recent models I've seen.

I am not understanding why the barrel link would be fitted to prevent the slide stop pin to act as a guide and "SUPPORT" for the barrel.

The lower lug on this barrel shows "absolutely no signs" that it has been contacted by the slide stop pin. You can rotate the barrel link through it range of motion and SEE that the hole doesn't come close to the surface of the barrel's lug. Therefore, the slide stop pin cannot touch the lower lug and act as a guide around the radius.

It has been written, that mass produced pistols can be fitted this way as long as the lower lug stands on the Slide stop pin at full lock-up. Although, this method will cause premature wear on the Link Pin.

1911Tuner ........... have any thoughts you could share on this matter ??
It would be appreciated

JF.

[robot1911]

Here's a little info for you. Most 1911's produced via the "assembler", mass-produced method during the past 50 years...or more...have the barrel floating free. I mean very little contact at the upper lugs and none on the lower barrel lugs.
It sounds to me like your barrel, if you intend to have a 'fitted' assembly, needs to have the lower lugs welded and then fit to the slide/lower barrel lugs/slide stop. Or, just get an oversize (gunsmith fit) barrel and have it fit to your pistol.
And yes guys, I'm aware that lots of 1911's these days are coming down the chute with fitted or at least semi-fit, barrels...but that's a fairly recent development, and most welcome. For instance, I've seen, over the past year or so, lots of Kimbers that were fit as well as it's possible to fit a custom pistol. And even many of them had decent triggers.
I've even seen some Springfields recently that had excellent barrel fitting done...and acceptable bushings.
So I'd have to say things are getting better.
But the case in point here...I'd sure check to see if it had barrel springing first and if so, relieve that bushing to stop it. Then make a decision about just how he'd like his pistol to perform and go from there. I just want him to know that there are literally millions of 1911's out there that are 'free-floaters' just like his...and they all shoot. Not 'well' but they do go 'bang' every time you pull the trigger.

Bob

[Iron bottom]

Well, I'm not exactly sure. Last week I put a Barsto in the 70 Repro I have. Cut the lugs with brownells cutter at full engagement. Using a piece of 0.200 and 0.156 drill rod and two links (0.283) on the outside of the lugs, I got the pin fitted to the lugs snugly. Put the barrel back in this pistol and it locked up out of battery. Turned out to be a small piece of leftover steel from cutting the lugs between the pin and lugs. Stopped the show. I got some clearence in there now. This is my reason for not having the pin ride the lugs too tightly except for lockup. I may be wrong, of course. I'm gonna shoot it this weekend and will know more.

The original Colt barrel I have shows no signs of wear on the lugs either. It's just the way Colt fits barrels and I am in no position to argue with them. Tuner may come along and enlighten us.

[Iron bottom]

Colt normally uses a 0.278 or #3 link. You say the link pin had been tampered with. Could there be a possibility the link has been changed from the original?

[Sniper350]

Robot1911 - Thanks Bob, your assessment sounds right on the money, because I feel the pistol left the factory with that over-sized barrel link.
Evidence being, that absolutely no finish wear can be seen on the lower lugs.

The pistol had some parts that needed replacing, but is shooting fine. My only concern is that the barrel link is the only thing achieving a safe vertical lock-up. Should the link break -- a dangerous situation will exist, as the barrel could be permitted to drop lower and loose its safe upper lug engagements !

Normally, with a properly fitted barrel, the link can break and the gun may/can still cycle without failure. The barrel will sit on the slide stop pin and be supported - maintaining the vertical engagments, so when the gun goes bang, the barrel won't go flying off somewhere.

It's hard to convince someone, with the pistol shooting fine, that he needs a new barrel or have the old one welded up so the lower lugs can be re-cut to fit the frame. But safety comes first ... that's why I wanted seek some advice here.

JF.

[Sniper350]

Iron Bottom - I don't think the Link has been tampered with -- there is no signs of wear to the lower lugs.

The owner has peened the Link Pin and Lower lugs in an attempt to keep the pin from falling out. I think this is due to the hole being oblonged out of shape from the force of supporting the barrel.

The link is not a #3 ............I compared it to a number 3 that I have on hand. I have not taken it out of the barrel to measure it yet. I didn't want to destroy the peen job that was done, until I fugure out what should be done.

You are correct, the link should not rub the lower lug tightly ......... barely touching it as a "guide" is the better fitment - I have been told. The LInk should guide the barrel at a smooth pace around the radius using the barrel's own inertia

JF.

[niemi24s]

Don't have any specs for 1911's other than the 5", full-sized types, but if the Commander specs are the same as USGI specs in the vicinity of the link, it WILL be riding the link (even a standard 278 link) when in battery.

This business of the barrel being forced up snugly into maximum lug engagement with the slide by slide stop pin contact with the barrel feet applies only to custom guns with hard-fit, initially oversized barrels.

The initial JMB design and the 1970-vintage U.S. Army blueprints result in the barrel riding the link with no vertical support by the slide stop pin/barrel feet when in battery. If you want the barrel supported by the SS pin you'll have to weld up your current barrel's feet (or get a another hard-fit, oversized barrel) and fit it.

Any manufacturer (including Colt) who builds a 1911 meeting U.S. Army specs for a Government Issue gun builds a link rider. The U.S. Army does have specifications for a National Match barrel (with oversized feet requiring fitting), but these are NOT the barrels installed in run-of-the-mill USGI 1911's. Regards.

[1911Tuner]

By invitation...

Riding the link is something that many pistols do, and it's not entirely a bad thing as long as the barrel doesn't actually stand on the link in full vertical engagement. (I refuse to say "lock" or "lockup" because the gun isn't locked when it's static/in-battery)

Riding the link excessively as the barrel cams up can cause a little feeding hitch if the bullet nost strikes the barrel ramp as it transitions from the feed ramp, but that's about the worst that it can do. Standing or "locking" on the link can cause problems, though.

I like to see the barrel ride the link just a tiny bit when the barrel is fully linked down and in bed because it prevents damage to the front radius of the lower lug...but no more than about .003 inch or so. By the time the barrel has actually started to cam up, the lower lug should be supported by the slidestop pin. Ideally, the cam-up should be shared equally by the lug and the link, with the link following the shape of the lug all the way in...but ideal is sometimes hard to get, so as long as the last bit of vertical engagement is handled by the lug and pin, all will be well.

The other drawback of standing on the link is that it degrades accuracy to some extent...the amount of which depends on the individual gun...because the barrel is literally standing on a narrow foot instead of utilizing the whole width of the lug.

[auto45]

Tuner,

Doesn't seem like a 'link-rider' would hold up for many tens of thousands of rounds like one properly fit? But, I suspect, few actually shoot enough rounds through a single gun to test it.

That would be a lot of pressure on the "narrow foot" as you mentioned. More on the slide stop also I would guess?

[Sniper350]

Thanks to all that have responded -- a lot of good information posted here.

It appears I was over reacting to the condition that I found - riding the link is more common place than I thought. I own (4) - 1911's and none of them ride the link to the extent I found in this combat commander. All of my 1911's show shinny surfaces around the radius of the lower barrel lugs.

Thanks to 1911tuner for your comments -- could you explain a test to perform so I can know to what extent the lower lug is standing on the slide stop pin at full vertical engagement ? Sorry if this test has already been covered by Hunter ? From your comments, I have learned that this is really the most important requirement from the barrel Link system.

I thought being able to push the barrel downward [ through the ejection port ] was a sign that the lower barrel lug was NOT being supported by the Slide Stop Pin. Someone else hinted that a worn barrel bushing could also cause this type of vertical movement under downward pressure ??

Thanks for any further info................

JF.

[1911Tuner]

That would be a lot of pressure on the "narrow foot" as you mentioned. More on the slide stop also I would guess?

Correct on both counts.


But, I suspect, few actually shoot enough rounds through a single gun to test it.

Correct again. 5% of the shooters do 95% of the shooting. The manufacturers know this, and that the average buyer won't put the guns to enough use to see a problem.
They're building what amounts to not much more than conversation pieces and toys.


Could you explain a test to perform so I can know to what extent the lower lug is standing on the slide stop pin at full vertical engagement ?

Swing the link to its vertical position and note how much of the upper part of the hole is visible below the upper radius of the lug.