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590A1 chambering issue

Discussion in 'Firearm Maintenance, Safety And Troubleshooting' started by ybrik, Oct 4, 2019.

  1. ybrik

    ybrik .410

    Messages:
    48
    Folks, need your help on this one.
    I'm having a chambering jam/hang-up on this 590A1 only when using live ammo 12G 2 3/4.
    In a box of 25 ammo, it will happen 2 or 3 times.
    But when I try to replicate it with snap caps loading them on the magtube, it doesn't have a hang-up. I even tried to cycle and chamber even pointing the muffle downwards and it feeds and eject smoothly.

    This happens only when I load the ammo in the ejection port and rack the slide forward.

  2. nitesite

    nitesite Sheepdog Moderator "Philanthropist"

    Messages:
    5,590
    You need to replicate it with the snap caps being loaded in the ejection port, like your occasional live ammo rounds.

    How exactly does the shell "jamb/hang-up"?

    With what ammo are you having this problem?
  3. ybrik

    ybrik .410

    Messages:
    48
    The shell jams up exactly as shown in the vid.
    This happened on Winchester dove-clay and S&B slug.

    So I replicated it this time loading the snap caps on the chamber. It loaded successfully everytime I racked the slide forward. I even tried with the A1 pointing down, so the snapcap would be way forward the elevator. Even the rifle pointing upwards where the snapcap is all the way back the elevator. All good on these tests.
    So I was thinking the condition that happened on the vid could be the crimp at the front on the ammo somehow catched and didn't slide forward along the elevator causing the bolt face ram the back of the cartridge.
  4. fellmann

    fellmann .270 WIN Supporter

    Messages:
    394
    Is the gun brand new ? Have you disassembly it ?
  5. ybrik

    ybrik .410

    Messages:
    48
    This is 3 years old and yes I have disassembled it regularly during cleaning.
  6. Hoserdad

    Hoserdad Copper BB

    Messages:
    3
    Does the tab on the lifter catch the front edge of the shell? I’ve never had a fail to feed in 10 years of abuse on mine.

    Attached Files:

    meanstreak likes this.
  7. fellmann

    fellmann .270 WIN Supporter

    Messages:
    394
    Okay.. Odd indeed.. Do you have a side saddle installed ?
    meanstreak likes this.
  8. ybrik

    ybrik .410

    Messages:
    48
    The tab on the lifter doesn't catch the front edge of the shell.
    Last edited: Oct 13, 2019 at 9:32 AM
    meanstreak likes this.
  9. ybrik

    ybrik .410

    Messages:
    48
    No side saddle installed.
    meanstreak likes this.
  10. ybrik

    ybrik .410

    Messages:
    48
    So upon further inspection, I dropped a 12g round into the ejection port in the elevator/lifter. When I slide the round by hand forward and background, there is a bit resistance. So that is from the inside part of the lifter in contact with the edge of the brass. When I do this with the snap cap, it is much smoother, for some reason that is an annodized aluminum. I tilt the A1 up and down, the snap cap round would slide back and forth. But with a live round, it doesn't, and just remains where it's at.
    Does this mean I have to polish the inside of the lifter? I haven't tried doing one. And this lifter is parkerized.
    meanstreak likes this.
  11. Hoserdad

    Hoserdad Copper BB

    Messages:
    3
    Only with a particular brand of ammunition? Light target load or slug? Maybe just a small burr needing removal?
    meanstreak likes this.
  12. ybrik

    ybrik .410

    Messages:
    48
    I have used light target loads on winchester and slugs on S&B and Winchester too. These are the only 2 brands I have shot with.
    meanstreak likes this.
  13. fellmann

    fellmann .270 WIN Supporter

    Messages:
    394
    Why i asked about the side saddle was because some people screw them on a bit to hard and squeese the aluminium receiver making it harder for things to operate :)

    Try the finest sandpaper you got and try remove the roughest areas on the lift
  14. ybrik

    ybrik .410

    Messages:
    48
    So I used 1000~1500 grit sandpaper to deburr/smoothen both inside arms of the elevator.
    [​IMG]
    [​IMG]
    [​IMG]

    Upon disassembly, it tried to check if the round would slide freely but noooopee it didn't:


    After deburring:


    I had an old elevator that mossberg replaced due to cracked elevator tabs/posts here:
    http://mossbergowners.com/forum/index.php?threads/590a1-cracked-elevator-posts.17658/

    Then after receiving this replacement, I had this chambering issue.
    I still had the old elevator and the insides were smooth and the rounds used to slide everytime.

    So I would need a range trip or trap shoot to test this fix, but I am hoping I have addressed this issue.
    bluesman66 likes this.

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