Mystery slide drag--help me out here.

original: forum.m1911.org
Retrieved: December 01, 2011
Last Post: August 23, 2009

Greg Bell
25th July 2009

I have an older special combat government and it is giving me a bit of trouble. If you pull the slide back and release it, you can feel drag during the last inch before the slide is completely forward. If you add enough resistance (by keeping my hand on the serrations) it will actually stop moving forward completely.

When I took it out I had a few malfunctions where the last round failed to chamber. I am pretty confident this drag issue is at least a part of that.

Here is what I have done so far to track down the problem.

1. I took the barrel out of the gun to see if it was in the rails. The slide moves smoothly in the tracks. There are no burrs or raised ridges that I can detect.

2. I removed the disconnector to see if it was dragging. I put the slide, barrel, bushing, etc on. The drag was still there.

3. I examined the rear of the barrel lugs. There seems to be a little wear at the rear of the lug closest to the chamber. Hmm.


Lazarus
25th July 2009

If the slide gets tight just before going into battery, the barrel lower lugs are fitted tightly against the slidestop pin. (maybe too tight). Or your link may be too long.


kenhwind
25th July 2009

Does this gun have a collet bushing in it?


Greg Bell
25th July 2009

I happen to have another Series 80 Colt. I swaped the slide stop out of it and the problem was still there.

Next I replaced the correct slide stop pin and put the other Series 80 barrel in and the problem went away. My guess is that the problem is in the barrel. Hmm. What is my next step?

P.S. Standard bushing.


1911Tuner
25th July 2009

Put the gun back together with the original barrel. Point it straight up and cycle the slide slowly, all the way back and all the way into battery. If the hitch is gone, repeat with it pointed straight down. If it gets worse than when it's held horizontal... the barrel is timing into the slide too early, and the lug corners are clashing instead of meshing. (Barrel lug front corners with slide lug rear corners.)

If this is a used gun it may have a longer barrel link in it. Is the barrel rubbing on the inside of the slide as the slide closes?


Greg Bell
25th July 2009

There is drag either way. Horizontal or vertical.


1911Tuner
25th July 2009

Quote:
There is drag either way. Horizontal or vertical.

Even when pointed straight up?


Greg Bell
25th July 2009

Yes. In fact, it may be slightly worse when pointed straight up.


1911Tuner
25th July 2009

That points to the barrel bushing getting into a bind as the barrel pivots and moves forward.

Try swapping out the bushings to see if it goes away.

Just in case... check to see if the barrel is riding high on the link, too. Even with a long link, it should eliminate or alleviate the problem with the muzzle pointed straight up... unless the link is seriously long... and even then, it won't normally get any worse.

Show him a drawin', niemi.


niemi24s
25th July 2009

This is the closest one I can find right know that might help:http://i129.photobucket.com/albums/...s/scan0006c.jpgIt depicts a mid- spec Gov't Model M1911A1 an instant after firing just as the slide lugs make contact with the barrel lugs and just as the slide begins to pull the barrel feet aft, away from the slide stop pin.

In battery before firing, the slide (blue) would be 0.0125 inch farther forward (to the left).

Will post a more applicable one - if I've got one - and can find it.


1911Tuner
25th July 2009

No... I meant a drawin' of a barrel with a long link... preferably in the in- battery position. That's a blueprint!


niemi24s
25th July 2009

I searched my files and don't have anything better than the one in Post #11.


Greg Bell
25th July 2009

I tried two other bushings. Same problem.

I need to compare the link to the links in my other 1911s.


Greg Bell
25th July 2009

Kuhnhausen seems to indicate that the lugs need to be lowered. I dunno. I will get back to this project tomorrow. Sadly, I really enjoy all this trouble shooting.

It seems likely the solution is something like what the Kuhnhausen manual suggests--since the other series 80 barrel dropped in with no drag. Tomorrow I will compare them with the ol' calipers.


niemi24s
26th July 2009

Quote:
I will get back to this project tomorrow.

When you do, it might be a good idea to measure the vertical locking lug engagement with the original parts. Measure the link too. All that will give you some idea of how much "working room" is available in the gun.

When you put the other barrel in (and the binding went away) was that with the other link or the original link?

If it was the other link, what are the sizes of each link?


Greg Bell
26th July 2009

Ugh. Hoping the solution would be so easy, I switched the .273 link that is in it out with a .268. It didn't help at all. Still plenty of drag.

I wonder why it had a .273 link in it? Hmm?

Anyway, any more suggestions?


1911Tuner
26th July 2009

Quote:
Anyway, any more suggestions?

'Fraid this one falls into the category of one that I'd have to see to diagnose and correct.


Greg Bell
26th July 2009

I did notice that the barrel from the SCG would not fit into my XSE. I think the hood is too wide. Probably unrelated but rates a hmmm.


1911Tuner
26th July 2009

Once in a while, one'll throw ya a curve. Apparently, this is one of'em.

Quote:
I did notice that the barrel from the SCG would not fit into my XSE. I think the hood is too wide. Probably unrelated but rates a hmmm.

The SXE has a narrower hood recess than the earlier, pre "Enhanced" models. All Colts built since they started that has it. Basically, the recesses are the same as the ones on Gold Cups. Dunno why they thought that was a good idea, unless it was to discourage using barrels other than theirs...but there it is.


1911Tuner
26th July 2009

Greg... Just for sheets and geegles... try a .278 link.

Look at the lower lug... at the curve where the link sits when the barrel is linked down.

Is there any peening or sign of hard contact there and on the slidestop pin?


niemi24s
26th July 2009

Quote:
Greg...Just for sheets and geegles...try a .278 link.

Then, if this doesn't change anything, try it with the link removed. Leave out the recoil spring so you can get a better feel for any dragging.

In your original post you said the dragging began when the slide was about an inch away from battery. When it's that far back, the barrel should still be laying on the bed with the link loose - just like the link wasn't in the gun.

If it drags with the 278 link and still drags with no link, then... then.... [ooh, my head's startin' to hurt!]


Greg Bell
27th July 2009

I tried the 278 link. No help. Sniffle.

I will try the no link thing.


niemi24s
27th July 2009

Quote:
I wonder why it had a .273 link in it?

How did you determine it had a .273 link in it?


1911Tuner
27th July 2009

Quote:
I tried the 278 link. No help. Sniffle.

Back to... gonna hafta see it in order to figger it out... but let's try one more thing.

Use a Sharpie marker to coat the whole top of the barrel hood, and the tops of the barrel lugs, and cycle the pistol a few times so we can see where the interference is.

Make sure that the inside of the slide and the barrel are dry and free of oil, or it'll give a false read.

If none of the ink is rubbed off... coat the barrel from mid-point to the muzzle and repeat.

As niemi noted... if the gun is binding an inch out of battery, t pretty much eliminates the link and lower lug. Binding in those areas would show up a quarter-inch or less from battery.

I've run into this a couple times... and it was a bushing to batterl problem. Once, the bushing was simply too tight. Another time... the bushing was bored slightly off-center.

While you're at it, cycle the gun to the rear, and check to see that the barrel is going fully to bed.


Greg Bell
27th July 2009

I have a bag of Wilson Combat Links. I found the one that matched the one I took out of the Colt. The Colt Link was heavily beveled.


niemi24s
27th July 2009

Quote:
The Colt Link was heavily beveled.

Please explain - maybe a picture would help.

The link blueprint shows the hole edges and its outer edges all have a bevel/chamfer.

Is this something different or unusual?


Greg Bell
28th July 2009

Well, the Wilson links I used as a reference are not beveled.


niemi24s
28th July 2009 Because the link has a designed-in loose fit with the link pin and slide stop pin, I think the bevels just keep the otherwise sharp link edges from chewing up the pins and its slot between the barrel feet.

Sounds to me like your Colt link is normal and Wilson skipped the bevelling to save a few cents (bottom line, bottom line!


Greg Bell
30th July 2009

NEW CLUE

Guys,

I dropped my series 70 barrel in the gun. The drag is there. It isn't with the XSE barrel I tried. What might this mean gurus? I can't see anything obviously wrong with the recesses in the slide.


1911Tuner
30th July 2009

The XSE barrel has a narrow hood. Sounds like the hood on your original barrel is binding up in its recess. Color the hood with a Sharpie and cycle it a few times to see where the contact is. Relieve lightly with a smooth mill file... LIGHTLY... and see if it improves.

If it does, color the lower lug feet and check for uneven contact.

Could be that the lug foot to slidestop pin engagement is throwin' the barrel cattywampus.


niemi24s
30th July 2009

Could the barrels that drag cause the drag because their outer bottom surfaces (in the chamber area at about the 5 and 7 o'clock positions) are rubbing on the slide's barrel bore?

I think this would ordinarily keep the barrel from falling all the way down to the bed at linkdown, but maybe if the barrel bore wasn't parallel to the slide bottom it would...


Greg Bell
31st July 2009

Working on it. Hey, thanks a lot for all your help guys.

I just marked up everything with ink and I noticed, more than anything, that a large amount was worn off the 12-3 oclock positions on top of the upper barrel (lugs).


niemi24s
31st July 2009

Does the dragging barrel fall all the way down to the frame bed when the slide's all the way back?


1911Tuner
31st July 2009

We're on the same wave-length, Dan. I asked that in Post 26, but I don't think I got an answer. Could be wrong, though. Lemme go look.

re:

Nope. We got off on the beveled hole thing.

You can put a chamfer in the holes with a countersink. Just stick it in and twist it by hand.


Bob_W
31st July 2009

I didn't see where you had tried to cycle the slide with the link removed. Did you try that and did it make any difference? If the slide is dragging as far away as 1" from battery I don't see the hood having anything to do with it.

The one thing that a few others have mentioned is how the barrel sets on the frame or how the lugs ride on the slide stop pin. For testing the slide stop, remove the original slide stop pin and use the shank of a #9 or #10 drill bit that will be a little smaller than the .200" diameter slide stop pin. You would not need the link for this test. Now does the slide cycle with drag or not. If not then the lower lugs are most likely are riding up on the slide stop pin as suggested earlier. If the drag is still there the barrel may be bottoming on the frame or the lower lugs are stopping the rearward travel before the barrel has dropped enough. The smaller drill shanks would allow the barrel to drop a little more than the stock pin. With the stock slide stop pin how much clearance do you have between the top of the barrel and the underside of the slide with the slide away from battery?

Let us know how you make out.


niemi24s
31st July 2009

Quote:
...cycle the gun to the rear, and check to see that the barrel is going fully to bed.

Does it?

And does it actually physically contact the bed - not just look like it does?


Greg Bell
12th August 2009

I shot about 200 rounds through her this weekend. The problem is 95% gone. And there were no malfunctions. Break in?


Greg Bell
23rd August 2009

Whatever the heck it was it is gone. I have put about 400 rounds through it in the last two weeks. The "drag" feel is completely gone. I wonder what the heck it was? I'll bet the reason the gun was so mint was the original owner took it out and got a bunch of malfunctions. I guess "break-in" is no myth.

This gun runs like a champ now. I took out the series 80 parts and replaced the mainspring, and little bit of stoning with the power custom fixture and I have a nice 3.75 pound trigger. A phenomenal gun and absolutely a keeper.

Now I need to bevel the dang magwell.


tophatjones
23rd August 2009

Weird that the problem went away like that. If everything else checks out, like the condition of the upper barrel lugs, then you're good to go.


Return to 1911 Archive