Shimming, best material

Discussion in 'General Airgun Chat' started by Petervw, Nov 2, 2015.

  1. Petervw

    Petervw Member

    Joined:
    Jan 26, 2011
    Messages:
    232
    Location:
    Belgium
    hi all,
    I want to shim a scope, needs to go up about 1 mm to clear the mag-ring off the breech
    I have really low mounts and the regular low mounts brings the scope up too high to my liking
    besides negatives is there something that will work the same or better ?

    thanks
    Peter
     
  2. RobF

    RobF Administrator Staff Member

    Joined:
    Mar 4, 2010
    Messages:
    12,194
    Location:
    Poole, Dorset
    Club:
    Parkstone Gun Club, South Dorset FTC, Southampton Buccaneers
    metal shims
     
  3. OzzyJ

    OzzyJ New Member

    Joined:
    Sep 24, 2013
    Messages:
    73
    Location:
    Aylesbury
    Club:
    North Oxon FTC
    As Rob said metal shims. I use aluminium from the cans of a well known drinks brand;)
     
  4. rich

    rich Active Member

    Joined:
    Nov 8, 2008
    Messages:
    1,679
    Location:
    Shebbear, N Devon
    The last ones I cut from one of those well-known cans miked at 0.11mm thickness.
     
  5. sportsmatch

    sportsmatch Member

    Joined:
    Jun 12, 2009
    Messages:
    771
    Location:
    Blackwood S. Wales
    Club:
    Quarry Rifles
  6. Ratinator

    Ratinator 77.74

    Joined:
    Jan 2, 2010
    Messages:
    2,701
    Location:
    stourport
    Club:
    Millride FTC / Nomads
    alternative material

    I use film negative to shim if needed, possibly a little thicker than soft drinks can.
     
  7. Tench

    Tench WHFTA World Champion 2016.

    Joined:
    Sep 23, 2009
    Messages:
    1,719
    Location:
    derby
    Think about it Peter, If Carlsberg made scope shims what would they use? :D
     
  8. Gary Martin

    Gary Martin sultans of spring

    Joined:
    Sep 24, 2011
    Messages:
    439
    Location:
    worcestershire
    Club:
    harriers field target
    shimming material

    i too use the well known soft drinks can, sometimes i use a not so well known soft drink can.
     
  9. Petervw

    Petervw Member

    Joined:
    Jan 26, 2011
    Messages:
    232
    Location:
    Belgium
    I'll go with Tench as I prefer beer to soft drinks ;)

    thanks guys

    Peter
     
  10. Deleted member 4175

    Deleted member 4175 Non member

    what if you need to shim about 2.5mm :eek:
     
  11. Sake-San

    Sake-San La Vieille Alliance

    Joined:
    Oct 6, 2014
    Messages:
    328
    Location:
    France 87
    Club:
    l'Association Francaise de Field Target
    Early 1970's Heinz bean tin, they do come up from time to time ;)
     
  12. snippy

    snippy Member

    Joined:
    Oct 11, 2015
    Messages:
    51
    Location:
    st austell cornwall
    Club:
    Dutchy
    What about a cheap set of feeler blades ?
     
  13. Gary Martin

    Gary Martin sultans of spring

    Joined:
    Sep 24, 2011
    Messages:
    439
    Location:
    worcestershire
    Club:
    harriers field target
    need a new barrel, one thats straight!
     
  14. Blackdog

    Blackdog New Member

    Joined:
    Sep 5, 2014
    Messages:
    15
    Front left hand wing of a 1968 morris minor is about the right thickness. Earlier examples are to thin due to corrosion.
     
  15. DEAN C.

    DEAN C. Steyr Convert

    Joined:
    Apr 27, 2009
    Messages:
    842
    Location:
    Doncaster
    Club:
    Emley Moor FTC
    You can buy engineering shimming material either steel or plastic from Cromwell tools.

    The plastic shims would be ideal and come in packs of varying sizes to try and get the best clearance.

    https://www.cromwell.co.uk/PCN4153730C
     
  16. MickyFinn

    MickyFinn I❤HFT

    Joined:
    May 7, 2013
    Messages:
    1,747
    Location:
    Matlock, Derbyshire
    Club:
    The Anston Massive & Kingsley HFT
    I've got a piece of this shimming my scope!:D
     
  17. DEAN C.

    DEAN C. Steyr Convert

    Joined:
    Apr 27, 2009
    Messages:
    842
    Location:
    Doncaster
    Club:
    Emley Moor FTC
    Where do they use that on a BMW?:rolleyes::D
     
  18. MickyFinn

    MickyFinn I❤HFT

    Joined:
    May 7, 2013
    Messages:
    1,747
    Location:
    Matlock, Derbyshire
    Club:
    The Anston Massive & Kingsley HFT
    Nope, they don't, it's courtesy of Mr Dutton ages ago at Emley Moor one day when I was struggling to zero in the Steyr/Nightforce combo.
     
    Last edited: Nov 4, 2015
  19. Lol Moore

    Lol Moore Banned

    Joined:
    Jan 6, 2013
    Messages:
    0
    Location:
    Chichester
    Club:
    Ford & Oaks
    Shimming paranoia

    The mechanics of shimming has always worried me, particularly with very expensive scopes.

    If you look at the relative angles involved it could easily be possible to damage something.

    Luckily my chosen discipline requires less slope to get on optical centre than the FT guys, but I still do it as carefully as I can.

    I personally use Aluminium foil but in a way that the geometry is less harsh, I take a long strip of foil that is cut just shy of the width of the mount, I then start to fold this back and forth with each fold slightly longer than the last, the length of each depends on how thick you want the final shim.

    This creates a shim that is profiled and more supportive, rather than one that not only shims up but reduces the mount diameter so much.

    I also use a torque wrench for tightening down - this doesn't completely remove the danger of crimping but in my opinion does reduce it.

    I think this shows what I mean:

    https://goo.gl/photos/tvF1rpoQPqT4qNn29

    Last time I did this I did work out how many MOA each fold gave but cannot remember what it was :confused:
     
  20. Adam

    Adam Active Member

    Joined:
    Jan 5, 2009
    Messages:
    918
    Location:
    Leeds
    Club:
    Redfearns & the UBC
    That's an interesting solution but the OP's requirement is to raise the whole scope by 1mm so both rings would be shimmed equally, hence no (extra) stresses. However I'm not convinced that the difference between low and ultra low mounts is worth all the effort. How much real world difference does a few mm up or down make?
     

Share This Page

  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice