Welcome to M1911.ORG
The M1911 Pistols Organization Forums Site


John needs your help
Please read this message.


Sponsors Panel
If you intend to buy something from the companies advertising above, or near the bottom of our pages, please use their banners in our sites. Whatever you buy from them, using those banners, gives us a small commission, which helps us keep these sites alive. You still pay the normal price, our commission comes from their profit, so you have nothing to lose, while we have something to gain. Your help is appreciated.
If you want to become a sponsor and see your banner in the above panel, click here to contact us.

Page 1 of 9 12345 ... LastLast
Results 1 to 10 of 87

Thread: Lowering Frame Bed

THREAD CLOSED
This is an old thread. You can't post a reply in it. It is left here for historical reasons.Why don't you create a new thread instead?
  1. #1
    Join Date
    16th July 2005
    Posts
    756
    Posts liked by others
    0

    Lowering Frame Bed

    I'm looking for suggestions, guys. I'm building the 2nd gun of a second set of matched pairs. This is a Caspian frame, Colt 80 slide, Kart NM barrel. The frame bed needs to be lowered .015 -.020", which is a lot of steel to remove accurately. As it sits now, the bed is so high that the slide wedges the barrel onto the frame as it's retracted.

    I'm assuming for the moment that the slide is ok, but I am gonna check that before lowering the frame bed. Also, I've checked and the barrel does not drop far enough in the slide yet, so the slide/barrel will have to be relieved as well, but it does drop farther than the frame will allow when assembled. Using a loose fitting 'work' bushing so that isn't the problem.

    Anyhow. Does anyone have a reliable method to remove metal to lower the frame bed? (From feed ramp to the end of the rails). Doing it with a round bar and emery cloth is ok for a couple of thou, but not for this much. No local access to a milling machine / operator I trust for this.

  2. #2
    Join Date
    1st June 2004
    Location
    Lexington, North Carolina...or
    Posts
    11,260
    Posts liked by others
    29

    Lowering the Bed

    A 64th inch+ is a lot of material to remove, and really not recommended. I limit it to about .005 inch max. Sounds like somethin's bad out of spec with either the slide or the frame. Have you contacted Caspian?

    Also a chance that it could be the barrel itself. Lay the barrel in the frame and push it down and back as far as it will go. Look through the slidestop pin hole to see if any of the lower lug is visible.

  3. #3
    Join Date
    29th July 2006
    Location
    Phoenix, AZ
    Posts
    957
    Posts liked by others
    6

    Now is the Time for Measurement

    You have already made a print of your new Caspian frame and Colt slide, right? And the numbers all appear to be within reason? How did the slide to frame fitting go?

    I'd say this one calls out for photos to document the process, since frame bed lowering is not part of the usual barrel fitting process.

    -Lazarus
    "Do not fix that which is not broken."

  4. #4
    Join Date
    16th July 2005
    Posts
    756
    Posts liked by others
    0
    Thanks, Mr. Tuner. I haven't contacted Caspian yet because I think I need to test this slide / barrel on a working frame first to be sure it isn't one of these. Not likely the barrel, but I am wondering about the slide.

    I'll do the other test you mentioned tonight, but I'm not understanding how that will test the barrel? There is no link involved yet, btw., and the feet are not hitting bottom.

  5. #5
    Join Date
    16th July 2005
    Posts
    756
    Posts liked by others
    0
    Hi Mr. Laz., the slide / frame fit is snug. I haven't lapped it yet - but it will travel full length with only a couple of tight (not too tight) spots.

    I'm not sure how to make a 'print' of the frame slide. Best I know to do is test known working slide/barrel on this frame, and this slide/barrel on known working frame. I'll do that tonight.

    I'm also not sure if my camera will get this sort of detail, nor if the operator is capable...but I'll try!

  6. #6
    Join Date
    1st June 2004
    Location
    Lexington, North Carolina...or
    Posts
    11,260
    Posts liked by others
    29
    Quote Originally Posted by gbw
    I'll do the other test you mentioned tonight, but I'm not understanding how that will test the barrel? There is no link involved yet, btw., and the feet are not hitting bottom.

    If you can see the forward radius of the lower lug through the hole, the barrel can't drop to the frame bed because the slidestop crosspin blocks it and will wedge the barrel between the slide and the pin. It just appears to be caught between the slide and frame. Caspian has a good rep for its frames and slides being well within spec, so I strongly suspect that this is your problem, especially if the Kart barrel is a full, or "Hard-Fit' type with oversized lower barrel lug.

  7. #7
    Join Date
    16th July 2005
    Posts
    756
    Posts liked by others
    0
    I'm sorry, I wasn't clear.

    No slidestop or link involved yet. Only slide, frame, barrel, bushing. I put the barrel/bushing in the slide, and then slide the frame on until the l.lugs hit the VIS. Then pressing the barrel down on the chamber SHOULD allow the slide to move to rear fully - is this correct? The slide will only move a short way before wedging the barrel, which is resting on the bed. At least that's what I see so far. It's a Kart NM hard-fit barrel.

    But I'm now thinking it's possible that the slide bore is too tight at bottom, and the vis / lug contact is forcing the barrel back up as the slide moves back...hmmm.

    So you're right (no surprise there!), it's gotta be either the frame or the slide. I THINK I'd have noticed if the barrel was that far out of whack, but I've been dumb before so there is precedent.

  8. #8
    Join Date
    1st June 2004
    Location
    Lexington, North Carolina...or
    Posts
    11,260
    Posts liked by others
    29

    Clear

    Okay. Is the barrel dropping low enough to get the lugs clear of the slide...so that the slide actually starts to pass over the top? If it is, you probably need to contact Caspian, though the problem may still be with the slide...or it may be a tolerance stack issue with slide, frame, and barrel.

    Just for funsies, try another barrel to see if it works, and measure the diameter at the chamber if it does. Then measure the distance from the
    rear face of the chamber to the rear face of the lower lug on both and see if there's a lot of difference.

  9. #9
    Join Date
    16th July 2005
    Posts
    756
    Posts liked by others
    0
    There's another idea I hadn't thunk of - I do have another new Kart barrel which I'll also try tonight, along with a working gun barrel.

  10. #10
    Join Date
    1st June 2004
    Location
    Lexington, North Carolina...or
    Posts
    11,260
    Posts liked by others
    29

    re:

    Tunefucious say:

    Always determine true nature of problem before using cutting tool on honorable frame.


Page 1 of 9 12345 ... LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  



Sponsors Panel
If you intend to buy something from Brownells, please use their banners above. Whatever you buy from them, gives us a small commission, which helps us keep these sites alive. You still pay the normal price, our commission comes from their profit, so you have nothing to lose, while we have something to gain. Your help is appreciated.
If you want to become a sponsor and see your banner in the above panel, click here to contact us.

Non-gun-related supporters.
Thank you for visiting our supporters.