1911 Barrel, Bushing and Slide Hangup

[edwardware]

I have a used mid-90's stainless Combat Commander with a barrel hangup. I noticed when I received it that if I cycle the slide with the muzzle down, the first inch or so of return to battery was very rough, and it would occasionally hang up entirely. Cycle it with the muzzle pointed up, no problem.

The factory bushing was very sloppily fit to the slide and barrel, and the outside of the barrel was also apparently machined with a rasp. I smoothed out the worst of the machine marks on the outside of the barrel, and fit a new LesBaer bushing just finger tight.

Now I find exactly the same problem (except it's smooth instead of gravelly): muzzle up and it returns to battery without a hitch. Muzzle down, and the bushing grabs the barrel, pulls it forward, and stops. Looking into the action when it's stuck open, I see that the barrel is lifted up off the frame bed by about 2mm, and forward a corresponding amount. Pushing the muzzle of barrel back toward the frame releases it, of course.

So where's the problem here? I know that the barrel is riding the link up into lockup based on examining the slide stop pin and barrel lugs. Is the link to long? A shorter link is going to compromise barrel/slide engagement.

You're expertise is appreciated.

 

[rcmodel]

Hole too big in the link?

A long link with an oval hole could perhaps cause what I think I understand what you are saying?
It locks tight, UP.
But doesn't pull it DOWN as far as it should?



Also, make sure the back bottom edge of the bushing isn't dragging on the barrel at link-down.
Commander length and shorter are especially prone to this.

Color the barrel with a black marker, the assemble the gun and cycle it.

If the back bottom edge of the bushing scrapes the marker ink off the barrel?
Chamfer & polish it.

rc

 

[edwardware]

RC: With the slide off, barrel and bushing installed in it, the rear of the bushing skirt is already oversized enough that it's not possible for the barrel to touch it; the only barrel/bushing contact is at the front of the bushing.

The link hole is loose on the pin, as I understand it should be, but it is round. The link is unlocking correctly, as I observe no damage to the locking lugs.

I've inked the barrel, and bushing is showing pretty even contact top and bottom for the full length of the barrel.

Is it possible that I should radius the bushing's interior contact with the barrel; not by increasing the size of the bushing opening, but by radiusing the contact? Alternately, I could slightly reduce and further polish the outside of the barrel starting 0.5" back from the muzzle.

Am I on the right track here?

 

[rcmodel]

Alternately, I could slightly reduce and further polish the outside of the barrel starting 0.5" back from the muzzle.

This.
A lot of Match barrels are made that way from the get-go.

1/2" is too much.
About 5/16" is about right.

rc

 

[BBBBill]

As issued barrel OD is about .580". Reduce by about .005" behind the muzzle.

 

[edwardware]

RC and BBBBill:

I've reduced the barrel down to about .575" from 0.313 from the muzzle back to just forward of the first locking lug, and further relieved and polished the inside of the bushing. The problem is about 95% gone. I guess a little more is called for

I haven't observed this behavior with any other 1911's? Isn't the slide hood supposed to 'slide' smoothly over the barrel and hold it down in the seat?

Thanks for your expertise. I really appreciate the help.

 

[DT Guy]

Not RC or BBBBill, but I believe it is due to the barrel torquing in the bushing as it rises and falls. Loose bushing to barrel fit can hide it, tighter fit can exacerbate.

Or maybe I'm wrong, and should have waited for RC or BBBBill?


Larry

 

[edwardware]

If someone's got another minute, I'm still curious: Isn't the slide hood supposed to 'slide' smoothly over the barrel and hold it down in the seat? How much vertical play should be barrel have between the frame seat and the slide hood.

Thanks again for your help.

RC and BBBBill:

I've reduced the barrel down to about .575" from 0.313 from the muzzle back to just forward of the first locking lug, and further relieved and polished the inside of the bushing. The problem is about 95% gone. I guess a little more is called for

I haven't observed this behavior with any other 1911's? Isn't the slide hood supposed to 'slide' smoothly over the barrel and hold it down in the seat?

Thanks for your expertise. I really appreciate the help.

 

[BBBBill]

With the slide retracted far enough for the barrel to be fully linked down (about 3/8"-1/2") there should be an absolute minimum of .015" clearance between the top of the barrel and the roof of the slide as measured by inserting a narrow feeler gage or other precision measuring device at the top front edge of the ejection port. I like to have .020" on mine. A wire (piece of guitar string works) is a good tool to use if you don't have a narrow feeler gage.

 

[edwardware]

With the slide retracted far enough for the barrel to be fully linked down (about 3/8"-1/2") there should be an absolute minimum of .015" clearance between the top of the barrel and the roof of the slide as measured by inserting a narrow feeler gage or other precision measuring device at the top front edge of the ejection port. I like to have .020" on mine. A wire (piece of guitar string works) is a good tool to use if you don't have a narrow feeler gage.

Great. How about a maximum clearance that's acceptable. Any guidance there?