SA 1911 Plunger tube difficulty

[jonas66]

Hey guys--

I have a 2010 SA G.I. model Champion. Safety got stuck- loose plunger tube.

When I pulled it apart, the plunger assembly was stuck in there pretty good. Had to use needle nose pliers to pull it out. The spring got a little boogered up.

I bought the Strobel tool and re-staked both legs. The tube was supported by a 7/64 bit shank which fit very snugly and the grooved clamp was correctly oriented. I used maybe 3/4 turn on the screw jack.
The rear holes inside the frame for the tube legs were already chamfered. I did not use any adhesive.
It appears to be firmly attached once more.

The tube does not appear to be crushed or damaged in any way, but there is no way I'm getting that plunger assembly back in there.

It was really tight - stuck - to begin with and now it's impossible.
I cleaned and lubed the plunger tube, polished the small plunger, even cleaned the opening edges of the tube lightly with a needle file, but no go.

So- do I buy the Brownell's reamers, or just get a new plunger assembly, or go ahead and yank the old tube to install a new one...is there any chance just running a 3/32 drill bit into the front (slide stop end) and a 7/64 into the rear (safety end) might work?

Looking for any insight, advice or comments...

I did read every thread a "1911 plunger tube" search brought up in this forum... to include a fair whack of posts by folks like Tuner and Fuff...

...edited for spelling...

 

[edwardware]

Based on what you're said, I would measure carefully to find the problem (tube crushed? how crushed? oversized plungers?) and probably ream the tube unless the misfit is bad enough that the result would be plungers too loose in the tube.

 

[jonas66]

ok, thanks edwardware.

So I need to look up the specs for the tube and plungers...how would I measure the internal diameter of that tube? Some kind of pin gauge/s? I'm not sure my calipers would do that accurately.

eta: I'm not any kind of smith or machinist...just curious and enjoy doing things for myself, so I don't have a lot of experience.

 

[Blue68f100]

How bad did the spring get messed up. A replacement spring is cheap, shipping will cost more.
Pin gauges are what you need to use to check the tube for damage. Try just the pins and see if they fit.

If it comes loose again, just replace the tube. The proper use of the tool swagging tool should not damage the part unless you really over torqued it crushing the tube. Then make sure it has a good chamfer before installing a replacement. When done right they never come loose.

 

[Nature Boy]

Or, you could just send it back to Springfield and have them fix it. They have a pretty dang good warranty.

I know, I know, that's not as fun as tinkering with it................

 

[jonas66]

I've been taking pictures...I'll post them in a minute.

Warranty...maybe? I'm the second owner, had it for 9 years...shoot re-loads in it...

eta: I'm not too awful worried about it- I know I could just buy new parts and put them on.
Just wanted to see if I could avoid that expense. (and trouble, and time...)

 

[jonas66]

Ok, here's a few pics:


Everybody talks about putting that kink in the spring to keep it from flying out- but I had to drag mine out with pliers.
That tube doesn't look 'crushed' to me, ...but I cannot get that spring and plunger assembly back in at all.

 

[Nature Boy]

Warranty...maybe? I'm the second owner, had it for 9 years...shoot re-loads in it...

SA warranty is for the lifetime of the product. Keep what you shoot through it between you and your priest

 

[jonas66]

"Forgive me Father, for I have sinned.
I have fired 250 rounds of steel-cased ammo through my 1911.
And yesterday had lustful thoughts about a box of primers."

 

[drband]

You likely would not be able to see a crushed plunger tube. I see three alternatives: 1. get and use Brownells plunger tube reamer, 2. Remove the bad tube and install a new part, 3. Send it to Springfield

Choose wisely!

 

[jonas66]

That's useful, drband- thank you. I wasn't sure if one could even see crush damage.

And- I'm not arguing for a pre-determined cheapest solution here- but I have heard it said that the brownell's reamers are actually just drill bits with a plastic handle- and that they tend to break. For $32.
Those were comments made over at Brownell's in the product section.

I mean, that's probably what I'll try first, that is- the reamers. If that doesn't work, then a new tube and assembly.

But would it be possible to use drill bits I already have?

 

[edwardware]

Duplicate duplicate.

 

[Blue68f100]

Your second picture appears to have a faint indication of flat on the tube. The spring is normally bent in the middle not at 1 end.

Have your tried just the pins?

You could chuck the pin in to a drill and sand the outer dia down a few 1/1000's till they fit. The spec for the tube hole is 0.109" +0.003", pin is spec at 0.107" -0.004"

 

[jonas66]

Excellent. Thank you, Blue68f100 - -I've been melting and cleaning up range scrap lead this afternoon; haven't had time to go look up the specs yet.

If I may ask, where do those numbers come from? Is that in Kuhnhausen?
And that's inner diameter spec for the hole, large end to small, and outer for the pins, correct?

The bend you see in that spring was caused --along with another which was re-bent in the process- by me dragging that thing out of the tube with needle-nose pliers in the first place. I'm not sure if the spring had the recommended 'kink' in it to begin with or not. It was in there tight, before I did anything to it.

By 'pins' you mean the plunger pieces, right?

Thanks again.

 

[jonas66]

So- .109" at the small end to .112" at the other, like that?
and then .107 for the small pin to .111 to the large?
...or is it .107 at the large end and .103 at the smaller?
Or am I completely missing the point?

Hey look, I don't mean to use you for a reference book.
I'll just go check here in a bit. But thanks!

 

[herrwalther]

Replacing the plunger assembly is pretty risky. The chance of damaging the entire frame is not worth it unless you absolutely have to. And at that point I would be looking to see if the warranty was still honored.

Put the detents back in one at a time minus the spring. You can use a small punch to knock them out if they get stuck. Just make sure to put the correct detent in each side. If they don't get stuck at all the problem was just the spring, easy as pie to order and replace. If they do get stuck, well that is where some work may be needed.

In that small a space, using the wrong reamer or drill bit can quickly remove too much metal. But for $31 for the plunger reamer you aren't risking too much. Another, lower cost option is to coat a small punch in lapping compound, in a drill chuck at low speed you can change the ID of the plunger tube. Lapping compound isn't very abrasive so you won't make the tube too think as long as you go slow. The down side is just annoying clean up once you are done.

 

[BBBBill]

The spring got a little boogered up.

Springs are cheap. Get a new one, put the correct "kink" in the middle, and add the detent pins.

I bought the Strobel tool and re-staked both legs. The tube was supported by a 7/64 bit shank which fit very snugly and the grooved clamp was correctly oriented. I used maybe 3/4 turn on the screw jack.

Good tool. Works well. I have had to shim the plunger tube support on one that I used before I bought mine. A drill bit shank is an OK substitute, but it doesn't support the small diameter end unless you use two different diameter drill bits. There is a better tool from Brownells that is dual diameter to support the tube al the way through.
080-707-000WB Plunger Tube Support

The rear holes inside the frame for the tube legs were already chamfered. I did not use any adhesive.
It appears to be firmly attached once more.

The chamfers may be enough, but I cannot really tell from the photo. What I can tell is that the legs of the plunger tube are too short. A common problem. They should be long enough to come through all the way to the inside of the frame in order to take advantage of the flared area. As is now the legs are flared into the straight walled part of the holes. Thhat will not hold long term.

The tube does not appear to be crushed or damaged in any way, but there is no way I'm getting that plunger assembly back in there.
It was really tight - stuck - to begin with and now it's impossible.
I cleaned and lubed the plunger tube, polished the small plunger, even cleaned the opening edges of the tube lightly with a needle file, but no go.

That confirms that it has been distorted. Another reason to replace it as they sometimes crack when straightening due to the thin walls.

So- do I buy the Brownell's reamers, or just get a new plunger assembly, or go ahead and yank the old tube to install a new one...

Yank and replace it yourself. Springfield is good, but they would likely use another tube with short legs as that is what their supplier likely provides.

You can find and download the 1911 blueprints from Rio Benson or send a pm with your email address and I will send it as a pdf attachment.

Replacing the plunger assembly is pretty risky. The chance of damaging the entire frame is not worth it...

I've replaced at least 100 over the years with never a problem with damage.

 

[jonas66]

BBBBill-- Thank you for the assessment and advice. I found the Rio Benson material. That's excellent.
I don't know how I hadn't seen that yet.
------------------
Obviously I'm open to any further advice or opinions, but I think I got what I was looking for here- a variety of input and options, a little food for thought.

I believe I'll be doing some reading followed by the purchase and install of a new tube and assembly.

I appreciate the time and effort y'all put into the assist. I just wasn't quite certain which way to go.

When I get it done I'll come back here and follow up just in case anyone is interested.

 

[drband]

Springs are cheap. Get a new one, put the correct "kink" in the middle, and add the detent pins.



Good tool. Works well. I have had to shim the plunger tube support on one that I used before I bought mine. A drill bit shank is an OK substitute, but it doesn't support the small diameter end unless you use two different diameter drill bits. There is a better tool from Brownells that is dual diameter to support the tube al the way through.
080-707-000WB Plunger Tube Support



The chamfers may be enough, but I cannot really tell from the photo. What I can tell is that the legs of the plunger tube are too short. A common problem. They should be long enough to come through all the way to the inside of the frame in order to take advantage of the flared area. As is now the legs are flared into the straight walled part of the holes. Thhat will not hold long term.



That confirms that it has been distorted. Another reason to replace it as they sometimes crack when straightening due to the thin walls.



Yank and replace it yourself. Springfield is good, but they would likely use another tube with short legs as that is what their supplier likely provides.

You can find and download the 1911 blueprints from Rio Benson or send a pm with your email address and I will send it as a pdf attachment.



I've replaced at least 100 over the years with never a problem with damage.

What a great resource! Thanks for sharing the Rio Bensen info!

 

[Blue68f100]

Excellent. Thank you, Blue68f100 - -I've been melting and cleaning up range scrap lead this afternoon; haven't had time to go look up the specs yet.

If I may ask, where do those numbers come from? Is that in Kuhnhausen?
And that's inner diameter spec for the hole, large end to small, and outer for the pins, correct?

The bend you see in that spring was caused --along with another which was re-bent in the process- by me dragging that thing out of the tube with needle-nose pliers in the first place. I'm not sure if the spring had the recommended 'kink' in it to begin with or not. It was in there tight, before I did anything to it.

By 'pins' you mean the plunger pieces, right?

Thanks again.

Yes, pins are the plungers.

Go here https://www.m1911.org/M1911-A1_REDUX.pdf

There are others out there too.

 

[Steve in Allentown]

I recommend that you follow BBBill's advice and replace the plunger tube. I'd also replace the plunger spring. Here's the tool that I've used for years: plunger tube staking tool.

Here are a couple of pictures showing a method for chamfering the leg holes.

Reaching in from the top of the frame to chamfer the holes isn't the easiest thing to do. A better way is to insert a round bit from inside the frame then chuck it into a Dremel. Be careful to proceed slowly so as not to create an unnecessarily large chamfer.

I don't use the bit shown in the picture. I use a diamond bit from Lasco. Makes this job easy and fast. Forgot to note that you have to cut the bit shaft in order to get the bit into the mag well.




Here's an example of slightly over cut chamfers. No harm done but not perfect.

 

[BBBBill]

...Reaching in from the top of the frame to chamfer the holes isn't the easiest thing to do. A better way is to insert a round bit from inside the frame then chuck it into a Dremel...

That's the way I do it, too. Way back in the dark ages a gunsmith named Colabaugh sold a specially ground cutter for that. Basiscally a mini dovetail cutter. I bought a bunch of them. When he stopped I switched to a ball head cutter as shown in the photo.
Note that trying to reach in from the top of the mag well and keep a spinning cutter in the hole that you're trying to chamfer is an exercise in frustration. You will likely end up with "pecker tracks" running across the inside wall of the magwell before you get the hang of it. It won't hurt the gun, but it will hurt your feelings and leave evidence of your crime.

 

[jonas66]

Thank you Steve in Allentown- nice advice.

BBBBill-- any recommendations? Wilson? Ed Brown? Nowlin? Does it matter, as long as the legs are long enough?

I see a half a dozen on Brownell's alone...

Just to clarify-- with Steve's pic- you would be inserting the cutter through the frame from the inside and then making the chamfer by pulling it back towards the frame, yeah?

Thanks for taking the time on a relatively simple problem, guys.
I appreciate it.

 

[Steve in Allentown]

Just to clarify-- with Steve's pic- you would be inserting the cutter through the frame from the inside and then making the chamfer by pulling it back towards the frame, yeah?

That is correct.

I imagine most plunger tube manufacturers make the legs long enough. FWIW, I use EGW.

Thanks for taking the time on a relatively simple problem, guys.

Simple problems are not always simple to fix. Always happy to help out a fellow devotee of the 1911.

 

[BBBBill]

BBBBill-- any recommendations? Wilson? Ed Brown? Nowlin? Does it matter, as long as the legs are long enough?

Like Steve, I use EGW.