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rescuerigger
04-29-2011, 8:39 PM
Problem: I have a new full size parkerized SA 1911 slide from a "Loaded" model that will not fit on a 40 year old full size parkarized SA "GI" frame. The rail cuts on the slide are just toooo tight and I can only get it about 1/2 onto the frame.

I would like the new slide cut to fit to the frame instead of the frame fit to the slide, if that makes sense. It just has to shoot reasonably well, no acurizing necessary. I fit the old busing and barrel and they seem to fit well on the new slide.

Am I barking up the wrong tree here? Any recommendations on someone to do this basic work?

Thank you for you time

tdaughg
04-29-2011, 9:43 PM
get a set of calipers and measure the frame rails and matching rails on the slide and see how far your off. from what it sounds like might be able to lap it and it would be a nice tight fit. also make sure theres no burrs on either part. worst case get out a file and spend some time working the slide.

unless something is really out of whack you should be able to get it working without too much work.

NewbieDave
04-29-2011, 9:54 PM
You can also try heating the slide before fitting. I know a old timer that built 1911... he use to heat the parts to hand fit them.


~dpc

rescuerigger
04-29-2011, 9:58 PM
If it went all the way on I would try the lap and "working it" recommendations. but is slides on only 1/2 inch.

The rails on both look in good condition. The new slide only had a few hundred rounds and is very sharp and clean. The frame is well used but only has a little shiny area. The original texture and finish is mostly there on the frame rails.

I figured both were mil spec and would just slide together.

Thanks for your inputs, I will consider them, but I am afraid to push and tweak the frame rails. I think I need to have the slide rails cut to match the frame unless there is something I am unaware of.

Any good smith recommendations for this basic fit work? No need for a high end custom shop. I am in the SF Bay Area.

Thanks

NiteQwill
04-30-2011, 12:59 AM
If you want a fast turnaround time, contact Dave Williams or Deb at the Springfield Custom Shop. They will help you.

Q619
04-30-2011, 3:11 AM
If you want a fast turnaround time, contact Dave Williams or Deb at the Springfield Custom Shop. They will help you.

This. Get it done right. You're going to have to blend the back of the slide and frame together anyhow and have it refinished. You'll also have to fit a new slide stop. SA will do a great job of it.

GSwain
04-30-2011, 6:53 AM
You can also try heating the slide before fitting. I know a old timer that built 1911... he use to heat the parts to hand fit them.


~dpc

Im sure if someone is very very skilled and has done this before, it works to get the slide over a sticky point. However this strikes me as a HORRIBLE idea, I cannot think of a faster way to get a slide stuck to a frame that doesn't involve a welder or a hydraulic press. WAY too much can go wrong here. :eek:

rescuerigger
04-30-2011, 7:33 AM
NewbieDave - If I was fitting something that was NOT suppose to move (sights, pins, etc), I would try the heating idea, but not on a slide. But any inputs are greatly appreciated. Thank you all. Keep them coming.


NiteQwill - Thanks for the info on SA custom shop. Do you have direct contact info for them?

All- Still taking ideas or recommendations for good smiths.

NiteQwill
04-30-2011, 8:46 AM
Deb
Springfield Custom
Springfield Inc.
420 West Main St.
Geneseo, IL 61254
800-680-6866, ext. 8920
800-617-6751
customshop@springfield-armory.com

ojisan
04-30-2011, 10:40 AM
This. Get it done right. You're going to have to blend the back of the slide and frame together anyhow and have it refinished. You'll also have to fit a new slide stop. SA will do a great job of it.

I'm not sure that the matching of the slide to frame length would be needed. I am familiar with this concept but between two SA made parts, it should be awfully close.

New slide stop?
Please explain why.
I have a couple of swap-top 1911s and use the same SS on each frame, regardless of what top end is used, no problems.
Each SS is matched to the frame and plunger, that is correct.
Are you refering to the notch in the slide that the SS engages needing work?
I'm not saying you are wrong, I'm curious to learn more.

Not clear in the OP's post is if he wants this as a permanent mate or just wants to slap the top end on for fun and limited shooting.
For a permanent mate, I would check both the frame and slide rails to see what needs tweaking to work best together. If the frame rails are curved or out of spec, they should be fixed, not the slide.
It could be the original slide was a "loose" one so it functioned on the frame just fine, but now that a tighter slide is at hand perhaps the frame is what needs work.
Doing out what truly needs to be done to fit it properly, even if frame work, should be done.
I understand your desire to leave the frame alone, and I too would look at things with an eye to making the slide fit the unmodified frame first.
For "temporary" use, the slide rails can be hogged out and widened enough to fit over any frame but accuracy could suffer.

OP: If you want to go permanent, it sounds like you have real nice pieces to start with that almost fit perfect already.
I agree with your assessment that basic fitting is something that can be done farily easily using hand tools and lapping compound.
While it is a 'basic" job, there is a bit to it to do it right.

Good luck finding an appropriate smith in your area, I have no info for you on this .

rescuerigger
04-30-2011, 11:00 AM
I dont know how the slide stop got into the tread. That is not the problem. The rails on the slide are too small.

Q619
04-30-2011, 4:17 PM
Not length, where they meet at the rear. They don't NEED to be flush/mated....you can have a pistol that looks like dung and still function. It doesn't matter that both parts are from Springfield. There isn't some gold standard spec that the rear of all slides and frames are held to. They're all blended to some degree or other. If they're uneven, they obviously weren't. This is done on a pistol by pistol basis. 1911's aren't AR's.

The slide off one of my CQB's will go onto the other....I mistakingly mixed them up when I was cleaning them both at the same time. The back of the slide wasn't flush with the frame. That's on a gun with a high degree of fitting. You're not going to find something different on a Springfield.

Regarding the slide stop, assuming he has both....one from the gun the slide came from and one from the frame: you've got one that was fitted to the barrel link and one that was fitted to the frame. If both were fitted exactingly, it should mesh up but most of the time: They're not going to be the same size. It's going to be looser than it should be somewhere. The slide stop and barrel link fitment is a critical thing. This is the high stress area. You don't want either getting beat up because of loose tolerances. Not if you actually plan on shooting it for a while without breakage. I actually forgot to mention that you may need to fit a new barrel link as well to get it to mate up cleanly with the slide stop hole in the frame. Poor fitment could also affect lockup engagement.

I'm definitely no expert, but when I fitted a slide stop on my old TRP I held with these numbers: slide stop pin diameter should be between 0.1985" and 0.2005". The slide stop pin hole in the frame should be between 0.201" and 0.203". That gives you a range of 0.0005" to 0.0045" of clearance. The bottom hole in the barrel link (the one the slide stop pin goes through) should be between 0.2045" and 0.2055". That puts the clearance between the link and the slide stop pin at 0.004" to 0.007".



I'm not sure that the matching of the slide to frame length would be needed. I am familiar with this concept but between two SA made parts, it should be awfully close.

New slide stop?
Please explain why.
I have a couple of swap-top 1911s and use the same SS on each frame, regardless of what top end is used, no problems.
Each SS is matched to the frame and plunger, that is correct.
Are you refering to the notch in the slide that the SS engages needing work?
I'm not saying you are wrong, I'm curious to learn more.

Not clear in the OP's post is if he wants this as a permanent mate or just wants to slap the top end on for fun and limited shooting.
For a permanent mate, I would check both the frame and slide rails to see what needs tweaking to work best together. If the frame rails are curved or out of spec, they should be fixed, not the slide.
It could be the original slide was a "loose" one so it functioned on the frame just fine, but now that a tighter slide is at hand perhaps the frame is what needs work.
Doing out what truly needs to be done to fit it properly, even if frame work, should be done.
I understand your desire to leave the frame alone, and I too would look at things with an eye to making the slide fit the unmodified frame first.
For "temporary" use, the slide rails can be hogged out and widened enough to fit over any frame but accuracy could suffer.

OP: If you want to go permanent, it sounds like you have real nice pieces to start with that almost fit perfect already.
I agree with your assessment that basic fitting is something that can be done farily easily using hand tools and lapping compound.
While it is a 'basic" job, there is a bit to it to do it right.

Good luck finding an appropriate smith in your area, I have no info for you on this .

rescuerigger
05-01-2011, 12:24 PM
Thanks for all the effort and time but ITS NOT A SLIDE STOP PROBLEM.

The slide rails are too tight and it wont even go onto the frame more than one centimeter before it gets stuck, and I mean will not budge.

Before this thread get more off track, I think I will send it to the Springfield shop to have the slide rails milled to match my frame.

I did not get any other suggestions for gunsmiths that could do this. Good gunsmiths must be a dieing bread. I think I will use the GI bill and take a class after I retire and go in to business for myself.

ojisan
05-01-2011, 12:58 PM
Sorry if the thread side tracked a bit on you.
Threads will do that, you know.
:)

You could buy a slide fitting file from Brownell's here:
http://www.brownells.com/.aspx/pid=849/Product/1911_AUTO_SLIDE_FRAME_RAIL_FILE

rescuerigger
05-01-2011, 1:13 PM
Thanks OJisa, that is the info I am looking for!

I can try that special file, it will save a few bucks sending it back to SA.

Oceanbob
05-01-2011, 1:23 PM
Maybe think about buying mil-spec slide instead of ruining a loaded SA slide.

It might be cheaper to buy a simple mil-spec slide than pay a Gunsmith to grind up your good slide.

Q619
05-01-2011, 1:33 PM
Thanks for all the effort and time but ITS NOT A SLIDE STOP PROBLEM.

The slide rails are too tight and it wont even go onto the frame more than one centimeter before it gets stuck, and I mean will not budge.

Before this thread get more off track, I think I will send it to the Springfield shop to have the slide rails milled to match my frame.

I did not get any other suggestions for gunsmiths that could do this. Good gunsmiths must be a dieing bread. I think I will use the GI bill and take a class after I retire and go in to business for myself.

It's actually pertinent to getting your gun up and running. You don't want advice: then don't ask questions.

Q619
05-01-2011, 1:37 PM
Maybe think about buying mil-spec slide instead of ruining a loaded SA slide.

It might be cheaper to buy a simple mil-spec slide than pay a Gunsmith to grind up your good slide.

So to avoid having his extra slide fitted to his frame he should buy another one and have it fitted to his frame....and have an extractor fitted, firing pin stop, barrel.........to SAVE?